Heat transfer engineering an international journal, tập 31, số 11, 2010

Heat Transfer Engineering, 31(11):907–909, 2010 Copyright C Taylor and Francis Group, LLC ISSN: 0145-7632 print / 1521-0537 online DOI: 10.1080/01457631003603816 editorial Application of Adsorption Technologies for Energy Efficiency KIM CHOON NG1 and BIDYUT BARAN SAHA2 Mechanical Engineering Department, National University of Singapore, Singapore Mechanical Engineering Department, Kyushu University, Japan Adsorption cycles are proven to be a practical and energy-efficient method for converting low-temperature waste heat into useful effects such as cooling, refrigeration, and heating Such cycles have direct environmental benefits in terms of global warming, emissions, etc This special issue covers the state-of-the art of adsorption research and technologies for relevant applications with the objectives of energy efficiency and sustainability The efficient utilization of energy at low heat source temperature is a key issue for both industry and academia In recent years, the heat-activated adsorption cycles are found to be most suited for converting low-temperature waste heat into useful effects, and this is reflected by the abundance of literature publications such as the study of adsorbent characteristics [1, 2], adsorption cooling [3, 4], adsorption heating [5, 6], adsorption refrigeration [7, 8], adsorption hybrid process [9], and adsorption process for automobile air conditioning applications [10]; the numbers of journal publications in these fields during the last three decades are shown in Figure In our opinion, the adsorption technology could be steered toward the key development of heat-activated machines for the energy industry, amounting to several billion dollars per annum, and these could offer cost-effective solutions for achieving energy efficiency and environment sustainability In cooling, refrigeration and heat pumping applications, new adsorption cycles have been developed This special issue of Heat Transfer Engineering was commissioned to focus on the recent developments of adsorption technologies for energy efficiency and environmental sustainability Several experts in many countries have been invited to address these adsorption technologies This special issue consists of six papers covering the aspects of adsorption fundamentals, chemical reaction kinetics Address correspondence to Professor Kim Choon Ng, Mechanical Engineering Department, National University of Singapore, Engineering Drive 1, Singapore 117576 E-mail: mpengkc@nus.edu.sg of consolidated adsorbents, a solar-powered adsorption cooling system, and an adsorption system for automobile applications The first three papers describe the adsorption fundamentals The first paper presents the adsorption isotherms of HFC-134a and highly porous activated carbon (Maxsorb III) measured using the constant-volume–variable-pressure (CVVP) method with temperatures ranging from 293 to 338 K and vapor pressures up to 0.7 MPa The isotherm data are presented with the Dubinin–Astakhov (DA) equation and correspondingly the heat of adsorption has also been determined, which is essential in designing the pressurized-bed adsorption cooling system The second paper examines the thermodynamic property surfaces for the adsorption of R507A, R134a, and n-butane onto the pitch-based activated carbons The property field formulation leads to the derivation of the entropy, enthalpy, internal energy, and heat of adsorption as a function of pressure, temperature, and the amount of adsorbate or P-T-q state With such governing equations, the entropy and enthalpy property maps are employed for analysis of adsorption cooling cycles and gas storage systems The comparison between the ideal and real adsorption cycles is highlighted using the thermodynamic approach The third paper studied the effect of air on kinetics of water adsorption on three promising adsorbents, namely, SWS1L (silica KSK modified by calcium chloride), silica gel of type RD, and FAM-Z02 (zeolites-based functional adsorbent material) For cooling applications, the experimental conditions selected are similar to those of real adsorption chillers The efficacy of adsorption cooling cycles is expressed in terms of the 907 908 K C NG AND B B SAHA [2] [3] [4] [5] Figure Number of journal publications in assorted adsorption fields over three periods (courtesy of Scopus search engine) specific cooling power at assorted partial pressures of residual air The fourth paper deals with the chemical reaction kinetics of consolidated composite adsorbent–ammonia working pairs using an iso-volumetric test unit The reaction kinetics, the heat transfer performances of the consolidated adsorbents, and the influences of the refrigerant condensation and the activation energy are analyzed, while the thermal conductivity of the consolidated adsorbents is determined by a transient plane-source method The study is useful for the selection of composite adsorbents having good heat and mass transfer characteristics for the adsorption cooling and heat pump applications The fifth paper presents an experimental solarpowered adsorption icemaker with double-stage mass recovery cycle with a regeneration temperature below 75◦ C and working at pressures just above atmospheric pressure The icemaker is found to be suited for low-temperature heat sources with continuous cold production The final paper presents the design and performance of an activated-carbon ammonia-based compact sorption generator for an automobile air-conditioning application It is reported that a pair of unit mass sorption generators could produce an average cooling rate of 1.6 kW when powered by radiator heat at a temperature of 90◦ C We thank all of the authors who have contributed to the success of this special issue and the valuable comments of reviewers that assisted in improving the quality of articles Lastly, we thank cordially Dr Afshin J Ghajar, editor-in-chief of Heat Transfer Engineering, for his invitation to commission the special issue REFERENCES [1] Aristov, Y I., Restuccia, G., Cacciola, G., and Parmon, V N., A Family of New Working Materials for Solid Sorption Air heat transfer engineering [6] [7] [8] [9] [10] Conditioning Systems, Applied Thermal Engineering, vol 22, no pp 191–204, 2002 Saha, B B., Chakraborty, A., Koyama, S., Lee, J B., He, J., and Ng, K C., Adsorption Characteristics of Parent and CopperSputtered RD Silica Gels, Philosophical Magazine, vol 87, no 7, pp 1113–1121, 2007 Saha, B B., Koyama, S., Kashiwagi, T., Akisawa, A., Ng, K C., and Chua, H T., Waste Heat Driven Dual-Mode, MultiStage, Multi-Bed Regenerative Adsorption System, International Journal of Refrigeration, vol 26, no 7, pp 749–757, 2003 Saha, B B., El-Sharkawy, I I., Koyama, S., Lee, J B., and Kuwahara, K., Waste Heat Driven Multi-Bed Adsorption Chiller: Heat Exchangers Overall Thermal Conductance on Chiller Performance, Heat Transfer Engineering, vol 27, no 5, pp 80–87, 2006 Li, T X., Wang, R Z., Wang, L W., and Lu, Z S., Experimental Study on an Innovative Multifunction Heat Pipe Type Heat Recovery Two-Stage Sorption Refrigeration System, Energy Conversion and Management, vol 49, no 10, pp 2505–2512, 2008 Akahira, A., Alam, K C A., Hamamoto, Y., Akisawa, A., and Kashiwagi, T., Experimental Investigation of Mass Recovery Adsorption Refrigeration Cycle, International Journal of Refrigeration, vol 28, no 4, pp 565–572, 2005 Amar, N B., Sun, L M., and Meunier, F., Numerical Analysis of Adsorptive Temperature Wave Regenerative Heat Pump, Applied Thermal Engineering, vol 16, no 5, pp 405–418, 1996 Tchernev, D I., and Emerson, D T., High Efficiency Regenerative Zeolite Heat Pump, ASHRAE Transactions, vol 94, no 2, pp 2024–2032, 1988 Dawoud, B., A Hybrid Solar-Assisted Adsorption Cooling Unit for Vaccine Storage, Renewable Energy, vol 32, no 6, pp 947– 964, 2007 Lu, Y Z., Wang, R Z., Jianzhou, S., Xu, Y X., and Wu, J Y., Practical Experiments on an Adsorption Air Conditioner Powered by Exhausted Heat From a Diesel Locomotive, Applied Thermal Engineering, vol 24, pp 1051–1059, 2004 Kim Choon Ng obtained his B.Sc (Hons.) and Ph.D from Strathclyde University in Glasgow, UK, in 1975 and 1980, respectively He worked briefly at the Babcock Power Ltd in Renfrew prior to joining in 1981the Department of Mechanical Engineering of the National University of Singapore, where he is now a tenured professor His areas of research are two-phase flow, chiller testing and modeling, electro-adsorption chillers, and renewable energy To date, he has written more than 200 peer-reviewed journal and international conference articles, six patents, and co-authored a book, Cool Thermodynamics, printed by CISP (UK) He is a member of the IMechE (UK) and the Institution of Engineers Singapore, a chartered engineer (UK) and a registered professional engineer (S), and an associate editor of Heat Transfer Engineering and of Proceedings of the Institution of Mechanical Engineers, Part E, Journal of Process Mechanical Engineering He also serves as an editorial board member for Advances in Mechanical Engineering vol 31 no 11 2010 K C NG AND B B SAHA Bidyut Baran Saha obtained his B.Sc (Hons.) and M.Sc degrees from Dhaka University of Bangladesh in 1987 and 1990, respectively He received his Ph.D in 1997 from the Tokyo University of Agriculture and Technology, Japan He worked as a senior research fellow at the Mechanical Engineering Department of National University of Singapore prior to joining the Mechanical Engineering Department of Kyushu University, Japan, heat transfer engineering 909 in 2010 as a professor His main research interests are thermally powered sorption systems, adsorption desalination, heat and mass transfer analysis, and energy efficiency assessment He has published more than 200 articles in peerreviewed journals and international conference proceedings He has edited three books and holds seven patents He serves as an editorial board member of Advances in Mechanical Engineering, Open Mechanical Engineering Journal (OMEJ), and Open Thermodynamics Journal (OTherJ) vol 31 no 11 2010 Heat Transfer Engineering, 31(11):910–916, 2010 Copyright C Taylor and Francis Group, LLC ISSN: 0145-7632 print / 1521-0537 online DOI: 10.1080/01457631003603949 Adsorption Parameter and Heat of Adsorption of Activated Carbon/HFC-134a Pair WAI SOONG LOH1 , M KUMJA,1 KAZI AFZALUR RAHMAN,1 KIM CHOON NG,1 BIDYUT BARAN SAHA,2 SHIGERU KOYAMA,3 and IBRAHIM I EL-SHARKAWY4 Mechanical Engineering Department, National University of Singapore, Singapore Mechanical Engineering Department, Kyushu University, Japan Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Japan Mechanical Power Engineering Department, Mansoura University, El-Mansoura, Egypt This article presents the adsorption isotherms of HFC-134a and activated carbon Maxsorb III measured using the constantvolume–variable-pressure method The adsorption isotherms cover temperature ranges from 293 to 338 K and pressures up to 0.7 MPa The trends of the experimental isotherms for activated carbon are found to be identical in all cases with previous studies except that the vapor uptake is slightly higher The adsorption characteristic of the Dubinin–Ashtakov equation has been regressed from the experimental isotherms data and the maximum specific uptake is 2.15 kg of adsorbate adsorbed per kilogram of activated carbon The heat of adsorption, which is concentration and temperature dependent, has also been extracted from the experiments INTRODUCTION Basic research on the adsorption characteristics of adsorbent– adsorbate pairs, such as HFC-134a and activated carbon (Maxsorb III), is motivated by the needs to switch to ozone-friendly working fluids, particularly for the heat-driven type of refrigeration cycles Such cycles could help in reducing the emissions of greenhouse gases, which is in line with the recommendations outlined in the Kyoto Protocol In recent years, there has been a substantial increase in interest in using adsorbent–adsorbate refrigeration cycles, as the activation temperatures are relatively lower, enabling waste heat recovery to be incorporated in plant designs Adsorption data, for the range of operational conditions of chillers, are unavailable from the manufacturers of adsorbents In general, only the data on surface area and pore volumes of the adsorbent are provided, and they are insufficient for engineers and designers to size the components of heat driven chillers For example, new adsorbents such as activated carbons may Address correspondence to Professor Kim Choon Ng, Mechanical Engineering Department, National University of Singapore, Engineering Drive 1, Singapore 117576 E-mail: mpengkc@nus.edu.sg have characteristics vastly different from those of conventional types The nexus of an adsorption cycle design is the determination of adsorption isotherms of adsorbent–adsorbate pair as well as the isosteric heat of adsorption, where extensive studies may be needed at various combinations of adsorbent–adsorbate pairs For example, Pons and Guilleminot [1] studied activated carbon/methanol system for ice production by using renewable energy source, while the applications of an AC135/methanol pair on refrigeration systems were investigated by Douss and Meunier [2] Miles and Shelton [3] tested experimentally a twobed system using activated carbon/ammonia as the adsorbent– adsorbate pair, and Wang et al [4] studied the adsorption characteristics of ACF/methanol and activated carbon (AC)/methanol pairs Vasiliev et al [5] developed a solar-gas solid sorption ACFs/ammonia-based heat pump Preliminary experimental data for hydrogen, helium, neon, and nitrogen on activated charcoal have been presented by Chan et al [6] Lin and Lin [7] studied the adsorption characteristics of HFC-134a on two types of activated carbon, namely, GAC and EAC (which are in granule and pellet form, respectively) for use in refrigeration and HFC recovery Riffat et al [8] determined the adsorption characteristics of refrigerants R407a, R407b, and HFC-32 with AX21 Akkimaradi et al [9] studied the adsorption isotherms for 910 W S LOH ET AL 911 EXPERIMENTAL SECTION Materials High-purity grade R134a samples, supplied by Kansai Coke Company, are used in the studies described in this article All properties of R134a are evaluated using the generalized equation of state proposed by Tillner-Roth and Baehr [10] The powderform activated carbon of the type Maxsorb III is used in the experiments for the determination of adsorption characteristics with the refrigerant HFC-134a A detailed photo of the pitchtype adsorbent, i.e., the Maxsorb III, is captured by the scanning electron microscope (SEM), as shown in Figure 1, while the BET (Brunauer–Emmet–Teller) surface area and micropore volume are respectively equal to 3.06 × 106 m2 kg−1 and 17.0 × 10−4 m3 kg−1 , respectively The skeletal density of the sample is about 2200 kg m−3 [11] Figure SEM picture of the activated carbon specimen Maxsorb III (200,000 magnification) Apparatus and Procedure HFC-134a on activated carbons Chemviron, Fluka, and Maxsorb II The present article reports on the ongoing effort toward generating experimental adsorption isotherm data for samples of activated carbon Adsorption isotherms of specimen Maxsorb III over a temperature range of 293–338 K and for pressures up to 0.7 MPa are measured using the constant-volume–variablepressure (CVVP) method The Dubinin–Ashtakov (DA) equation has been employed to evaluate the adsorption isotherm characteristics In addition, the isosteric heat of adsorption is extracted from the experimental isotherms data Based upon the adsorption parameters, the performance analysis of an idealized adsorption cooling cycle is presented The experimental apparatus consists mainly of a stainless steel (SS 304) adsorption cell and a charging cell with internal volumes of 59.69 ml and 1026.15 ml, respectively Maxsorb III activated carbon, 2.9283 ± 0.0001 g, is charged into the adsorption cell, simulating the bed design of an adsorption cooling system, and this low amount of adsorbent gives monolayer behavior during vapor uptake or regeneration Figure shows a schematic diagram of the experimental apparatus, where the dosing and charging cells are connected through a capillary tube The cells are immersed in a constanttemperature water bath (HAAKE F8-C35) and are controlled to preselected temperatures of to 95◦ C with an accuracy of ±0.01◦ C The pressure readings are measured using a 0–1 MPa Figure Schematic arrangement of adsorption isotherm experimental setup heat transfer engineering vol 31 no 11 2010 912 W S LOH ET AL range KYOWA pressure transducer (PGS-10KA) with an uncertainty of 0.1% of full scale in measurement A redundant secondary indicator of a 0–1.6 MPa range Bourdon pressure gauge is also used A class-A type Pt 100- resistance temperature detector (RTD) ±0.1 K is used for temperature measurement At the adsorption cell, the RTD is in contact with the activated carbon to enable direct temperature measurement All temperature and pressure readings are monitored by an Agilent data logger A thermostat-controlled tape heater is wrapped around the connection tubes to prevent condensation Due to the continuous circulation of the bath fluid, and the adequate time for thermal stabilization, it is assumed that no temperature gradient would occur within the cells Prior to the start of measurement, the entire assembly is evacuated for 24 h using a BOC Edwards direct drive vane vacuum pump to a vacuum level of 0.05 mbar During the evacuation, the adsorption cell was maintained at 120–130◦ C to desorb any residue gas in the cell Helium gas is injected into the system during desorption to improve the evacuation After evacuation, the charging cell is pressurized with R134a from its source (with ball valve closed), and the initial pressure and temperature are then recorded The R134a vapor is released into the adsorption cell and left to reach an equilibrium state Subsequently, the temperature of the bath is changed and the next data point along an isochore is obtained The measurements are at 20, 25, 45, and 65◦ C The same procedures are repeated with a different initial quantity of gas being charged into the charging cell For a low initial charge, it is possible to bring a system pressure within the cell to below bar The upper pressure was limited to 0.7 MPa in the experiment This precaution was necessary to avoid the possibility of condensation of R134a in the capillary At an initial stage of the experiment, adsorbate (R134a vapor) is introduced into the charging cell of a known volume In the absence of the adsorbent, the initial mass of adsorbate is calculated from the following equation: mi = ρab i P , Tcharging Vcharging cell (3) where ρab i is the initial adsorbate density at charging temperature, Tcharging and Vcharging cell is the charging cell volume When the dosing and charging cells are connected, adsorption occurs in the pores of the adsorbent and the void volume Vvoid in the adsorption cell is given by Vvoid = Vad cell − mac ρ − vµ mac solid (4) where Vad cell is the adsorption cell volume, mac is the mass of activated carbon Maxsorb III in the adsorption cell, ρsolid is the solid density of activated carbon, and vµ is the micropores volume of activated carbon The analysis presented here assumes that the total micropores volume of adsorbent is constant With a charge of 2.9283 g of Maxsorb III (measured by a Computrac Max 5000 moisture analyzer with resolution of 0.1 mg) is packed into the cell of 60.0 cm3 , the void volume of adsorption cell is equal to 53.4 cm3 This volume is inclusive of the vapor space of the adsorption cell, and the adsorbate mass is calculated using the generalized equation of state proposed by Tillner-Roth and Baehr [10] at respective adsorption temperatures, Tads , and pressures, i.e., mvoid = ρab (P , Tads ) Vvoid at Tads (5) where ρab is the density of gas (adsorbate) in the adsorption cell The remaining amount of adsorbate at each isotherm is calculated from mf = ρab f (P , Tads ) Vtotal (6) where Vtotal = Vcharging cell + Vvoid , ρab f is the adsorbate density at the respective isotherm temperature The total mass of the control volume at initial and final stage are respectively RESULTS AND DISCUSSION Data Reduction The quantitative amount of adsorbed adsorbate is determined for the generation of isotherms of the single-component adsorbate and adsorbent system (R134a–Maxsorb III) For a given amount of adsorbate contained in a system, the temperature, volume, and pressure are dependent variables and are related by the general form: f (P , V , T ) = (1) mtotal,i (P , T , C) = mab,i (P , T ) + mads,i (P , T , C) + mac,i (P , T ) (7) mtotal,f (P , T , C) = mab,f (P , T ) + mads,f (P , T , C) + mac,f (P , T ) (8) From conservation of mass, mab,i (P , T ) + mads,i (P , T , C) + mac,i (P , T ) or simply known as the equation of state (EOS) With a closed but adsorbent filled vessel, i.e., constant volume, the variable V can be treated as a constant (thus ignored) and the modified equation of state of the adsorbent–adsorbate pair would incorporate the concentration of vapor uptake that resides within the pores of adsorbent, i.e., Since the mass of activated carbon, mac is constant, and there is no adsorption at the initial stage, the preceding equation reduces to f (P , T , C) = mab,i (P , T ) = mab,f (P , T ) + mads,f (P , T , C) (2) heat transfer engineering = mab,f (P , T ) + mads,f (P , T , C) + mac,f (P , T ) (9) vol 31 no 11 2010 (10) W S LOH ET AL Hence, the amount of refrigerant adsorbed, mads , can then be estimated from mads (P , T , C) = mi (P , T ) − mf (P , T ) (11) which is dependent on all three pressure, temperature, and specific uptake factors Finally, the specific uptake value or the loading, C, is determined as C = mads mac (12) Adsorption Parameters Using DA Equation The Dubinin–Astakhov (DA) equation [12] is found to provide the best representation of the adsorption data In the analysis, the DA equation (13) is used to evaluate the temperatureindependent characteristic curve: ln(W ) = ln(Wo ) − n A E (13) where A is the adsorption potential and W is the adsorbed volume, Wo is the limiting volume of adsorption space of the adsorbent, E is the characteristic energy of the adsorption system, and n is the structural heterogeneity parameter The adsorption potential is the work done in the isothermal compression of kg of vapor from the equilibrium pressure, P , to the saturation vapor pressure, Ps , and is given by Ps P A = RT ln (14) Similarly, Eq (13) can be expressed as: W = Wo exp − RT E n Ps P ln (15) where the logarithmic form of Eq (14) is: ln (W ) = ln (Wo ) − RT E ln Ps P n (16) 913 liquid specific volume Above the saturation temperature, different approximations need to be used The method suggested by Dubinin [12] was the most appropriate one to represent the adsorption data for HFC-134a Consequently, vab = vboil exp [α (T − Tboil )] α = ln b vboil (Tc − Tboil ) (19) (20) where v is the saturated specific volume and the subscripts ab and boil refer to the thermodynamic conditions of the adsorbate in the adsorbed state and at its normal boiling point, respectively; Tc is the critical temperature of the adsorbate, and b is the van der Waals volume For HFC-134a, Tboil = 246.78 K, Tc = 374.21 K, vboil = 7.2643 × 10−4 m3 kg−1 , and b = 9.39 × 10−4 m3 kg−1 The numerical values for the adsorption parameters can be regressed from the experimental data; i.e., Wo , E, and n are equal to 0.001711 m3 kg−1 , 79.7 kJ kg−1 , and 1.37, respectively Figure shows the uptake of Maxsorb III–HFC 134a plotted against the pressure–concentration–temperature plane The shapes of the isotherms obtained from the current experimental are similar in all cases and comparable with previous study [9], which is shown in Figure The uptake values of HFC 134a onto Maxsorb III/R134a are generally higher than for the Maxsorb II–HFC-134a system This spread of specific uptake can be ascribed to the variability in the surface area and pore distribution of the adsorbent It is therefore important for designers to understand the adsorption characteristics of the specimen they anticipate using This is because it is rarely possible to extrapolate the isotherm characteristics are from one specimen to another DA equations with and without volume correction are fitted onto the experimental data in Figure The DA equation with volume correction has higher uptake value compared to the DA equation without volume correction at lower pressures and temperatures, and vice versa From Figure 5, both the DA equations have good approximation onto the experimental uptake values Figure makes a comparison of both the isotherm equations, Also in the current study, the experimental isotherms are crosschecked through the following methods: i) With no adsorbed volume correction, whereby Eq (15) reduced to ln (C) = ln (Co ) − RT E ln Ps P n (17) ii) With adsorbed phase volume correction, where the adsorbed volume W in Eq (15) is expressed as: W = Cvab (18) where vab is the specific volume of the adsorbed phase of the adsorbate As the volume of adsorbed phase cannot be measured directly, it is considered equivalent to the corresponding heat transfer engineering Figure Isotherms of Maxsorb III/HFC-134a at respective temperature vol 31 no 11 2010 914 W S LOH ET AL wherein the error between experimental and calculated uptake between fitted (i.e., both with and without volume correction) equations are plotted From Figure 6, the difference between experimental data and fitted results fall within ±0.13 kg kg−1 Heat of Adsorption Heat of adsorption, which is a function of concentration, has a weak dependence on temperature [9, 13] The Clausius– Clapeyron equation is commonly used to estimate heat of adsorption at constant concentration, as Hads = Figure Comparison of isotherm data for Maxsorb III/HFC-134a and Maxsorb II/HFC-134a systems at 293 K ∂ (ln P ) ∂T heat transfer engineering + T νg ma dP (P , T ) (22) dT where the first term of the right-hand side indicates the conventional form of the isosteric heat of adsorption derived from the Clausius–Clayperon equation and the second term defines the behavior of adsorbed mass with respect to both the pressure and the temperature changes during an adsorbate uptake, which occur due to the nonideality of the gaseous phase Using the DA equation, Eq (21) can be written as: Hads = hfg + E ln Figure Comparison of uptake deviations between calculated and experimental uptake: (i) at 20◦ C, • without volume correction, ◦ with volume correction; (ii) at 25◦ C, without volume correction, with volume correction; (iii) at 45◦ C, without volume correction, with volume correction; and (iv) at 65◦ C, without volume correction, with volume correction (21) Hads denotes the isosteric heat of adsorption (kJ kg−1 ), R is the gas constant (kJ kg−1 K−1 ), P is the equilibrium pressure (kPa), and T is the adsorbent temperature (K) Critoph [14] proposed a relation that is integrated from Eq (20) to estimate the isosteric heat of adsorption In the current study, the heat of adsorption, Hads as a function of vapour uptake is calculated from the measured adsorption isotherm by a correlation proposed by Chakraborty et al [15], i.e., Hads = RT Figure Isotherm data for Maxsorb III/HFC-134a for experimental data points ( ); for DA equation without volume correction (—); and for DA equation with volume correction (- - -) −R∂ ln P ∂(1/T ) Co C 1/n + T vg dP (P , T ) dT (23) where νg is the specific volume of the vapor phase, and dP /dT represents the gradient of the pressure with the temperature of the adsorbate The isosteric heat of adsorption for R134a on Maxsorb III as a function of surface loading and temperature is shown in Figure From Figure 7, one observes that Hads decreases with increasing vapor uptake Since Maxsorb III is highly porous with micropores of different widths, HFC-134a is adsorbed rapidly onto the sites of high energy During adsorption, molecules are adsorbed onto sites of decreasing energy The HFC-134a molecules first penetrate into narrower pores, resulting in a stronger interaction between the adsorbate and the adsorbent This implies a higher value of Hads at lower loadings After completely filling the smaller pores, HFC-134a molecules are accommodated gradually in larger pores, in which the adsorption affinity becomes weaker A monotonic decrease in the Hads as a function of loading is therefore observed vol 31 no 11 2010 W S LOH ET AL Tc Tcharging V Vvoid Vad cell Vcharging cell Vtotal W 915 critical temperature, K charging temperature, K volume, m3 void volume, m3 adsorption cell volume, m3 charging cell volume, m3 total internal volume of experimental setup, m3 adsorbed volume, m3 kg−1 Greek Symbols Figure Heat of adsorption using corrected correlation (Eq 24) at: (i) 20◦ C, , (ii) 25◦ C, ♦, (iii) 45◦ C, , and (iv) 65◦ , ρ ρab ρab i CONCLUSIONS ρab f In this study, the experimental isotherms have been derived for the activated carbon Maxsorb III/HFC-134a pair, which is useful for the design of adsorption chiller cycles We have found that the Dubinin–Ashtakov equation is most suitable to represent the isotherms both with and without volume correction, and the maximum uptake is found to be around 2.15 kg kg−1 Similarly, heat of adsorption is evaluated from the proposed transformation (Eq (22)) and it varies from 180 to 420 kJ kg−1 , depending on the adsorbate loading or uptake Such basic experimental isotherms and isosteric heat of adsorption of Maxsorb III/R134a system can be used in the design and analysis of adsorption processes in cooling applications ρsolid µ NOMENCLATURE A C Co E hfg mac mad mi mf mvoid n P Ps R T Tads adsorption potential, kJ kg−1 adsorption capacity per unit mass of adsorbent at equilibrium, kg kg−1 maximum uptake, kg kg−1 characteristic energy of the assorted adsorbent/adsorbate pair, kJ kg−1 specific enthalpy difference between saturated vapor and saturated liquid, kJ kg−1 mass of activated carbon, kg mass of vapor adsorbed, kg initial mass of adsorbate, kg final mass of adsorbate, kg mass of adsorbate in void volume, kg exponential parameter describes isotherm, dimensionless pressure, kPa saturated pressure, kPa gas constant, kJ kg−1 K−1 temperature, K adsorption temperature, K heat transfer engineering ∂ vµ density, kg m−3 density of adsorbate in void volume, kg m−3 initial density of adsorbate in charging cell, kg m−3 final density of adsorbate in both charging and adsorption cell, kg m−3 solid density of activated carbon, kg m−3 micropores electrical resistance, ohm partial derivative operator micropores volume, m3 Subscripts ab ac ads c f fg i o adsorbate adsorbent or activated carbon adsorption critical final difference in property for saturated vapor and saturated liquid initial limiting value REFERENCES [1] Pons, M., and Guilleminot, J J., Design of an Experimental Solar Powered, Solid Adsorption Ice Maker, Journal of Solar Engineering-Transactions of the ASME, vol 103, no 4, pp 332– 337, 1986 [2] Douss, N., and Meunier, F., Effect of Operating Temperatures on the Coefficient of Performance of Active Carbon–Methanol Systems, Heat Recovery Systems and CHP, vol 8, no 5, pp 149–169, 1988 [3] Miles, D J., and Shelton, S V., Design and Testing of a Solid-Sorption Heat-Pump System, Applied Thermal Engineering, vol 16, no 5, pp 389–394, 1996 [4] Wang, R Z., Jia, J P, Zhu, Y H, Teng, Y., Wu, J Y., Cheng, J., and Wang, Q B., Study on a New Solid Absorption Refrigeration Pair: Active Carbon Fiber–Ethanol Pair, Transactions of ASME, vol 119, pp 214–218, 1997 vol 31 no 11 2010 948 Cp D H h I LDPE m ˙ m n N1/2C P Q R RHM RLM T t x x¯ x0 R G OLIVEIRA ET AL specific heat, kJ kg−1 K−1 parameter of the Dubinin–Astakhov equation enthalpy, according to the Clapeyron equation, kJ kg−1 enthalpy, kJ kg−1 insolation, W m−2 low-density polyethylene mass, kg mass flow, kg.s−1 exponent of the Dubinin–Astakhov equation daily number of regeneration of adsorption phases per unit area of solar collector, phases m−2 pressure, Pa heat, kJ universal gas constant, kJ kg−1 K−1 reactor with high or medium pressure reactor with low or medium pressure temperature, K time, s uptake, kg kg−1 mean uptake, kg kg−1 maximum uptake, kg kg−1 Greek Symbols m T ε η variation of ammonia mass during the adsorption and desorption phases, kg variation of temperature, K error efficiency Subscripts A.C Ad Am Bed Ds Ev fl il In Ice HTF lv Max NH3 nri Out R Rc ri S activated carbon adsorption ambient adsorbent bed desorption evaporator final initial inlet ice produced during one cycle, related to useful cooling capacity heat transfer fluid liquid–vapor maximum ammonia nonrandom and dependent outlet regeneration reactor random and independent sensible heat heat transfer engineering Sat SC sl SS U W saturation solar collector solid–liquid stainless steel useful water REFERENCES [1] Chua, H T., Ng, K C., Malek, A., Kashiwagi, T., Akisawa, A., and Saha, B B., Modeling the Performance of Two-Bed, Silica GelWater Adsorption Chillers, International Journal of Refrigeration, vol 22, pp 194–204, 1999 [2] Nu˜nez, T., Mittelbach, W., and Henning, H M., Development of an Adsorption Chiller and Heat Pump for Domestic Heating and Air-Conditioning Applications, Proc 3rd Int Conf Heat Powered Cycles, Cyprus, 2004 [3] Liu, Y L., Wang, R Z., and Xia, Z Z., Experimental Study on a Continuous Adsorption Water Chiller With Novel Design, International Journal of Refrigeration, vol 28, pp 218–230, 2005 [4] Liu, Y L., Wang, R Z., and Xia, Z Z., Experimental Performance of a Silica Gel–Water Adsorption Chiller, Applied Thermal Engineering, vol 25, pp 359–375, 2005 [5] Wang, R Z., Wu, J Y., Xu, Y X., Teng, Y., and Shi, W., Experiment on a Continuous Heat Regenerative Adsorption Refrigerator Using Spiral Plate Heat Exchanger as Adsorbers, Applied Thermal Engineering, vol 18, pp 13–23, 1998 [6] Wang, R Z., Li, M., Xu, Y X., and Wu, J Y., An Energy Efficient Hybrid System of Solar Powered Water Heater and Adsorption Ice Maker, Solar Energy, vol 68, pp 189–195, 2000 [7] Wang, L W., Wu, J Y., Wang, R Z., Xu, Y X., and Wang, S G., Experimental Study of a Solidified Activated Carbon–Methanol Adsorption Ice Maker, Applied Thermal Engineering, vol 23, pp 1453–1462, 2003 [8] Tamainot-Telto, Z., and Critoph, R E., Adsorption Refrigerator Using Monolithic Carbon–Ammonia Pair, International Journal of Refrigeration, vol 20, pp 146–155, 1997 [9] Szarzynski, S., Feng, Y., and Pons, M., Study of Different Internal Vapour Transports for Adsorption Cycles With Heat Regeneration, International Journal of Refrigeration, vol 20, pp 390–401, 1997 [10] Saha, B B., Akisawa, A., and Kashiwagi, T., Solar/Waste Heat Driven Two-Stage Adsorption Chiller: The Prototype, Renewable Energy, vol 23, pp 93–101, 2001 [11] Saha, B B., Koyama, S., Kashiwagi, T., Akisawa, A., Ng, K C., and Chua, H T., Waste Heat Driven Dual-Mode, Multi-Stage, Multi-Bed Regenerative Adsorption System, International Journal of Refrigeration, vol 26, pp 749–757, 2003 [12] Saha, B B., Koyama, S., Ng, K C., Hamamoto, Y., Akisawa, A., and Kashiwagi, T., Study on a Dual-Mode, Multi-Stage, MultiBed Regenerative Adsorption Chiller, Renewable Energy, vol 31, pp 2076–2090, 2006 [13] Alam, K C A., Akahira, A., Hamamoto, Y., Akisawa, A., Kashiwagi, T., Saha, B B., Koyama, S., Ng, K C., and Chua, H T., Multi-Bed Multi-Stage Adsorption Refrigeration CycleReducing Driving Heat Source Temperature, Transactions of the Japan Society of Refrigerating and Air Conditioning Engineers, vol 20, pp 413–420, 2003 vol 31 no 11 2010 R G OLIVEIRA ET AL [14] Oliveira, R G., Silveira, V., Jr., and Wang, R Z., Experimental Study of Mass Recovery Adsorption Cycles for Ice Making at low Generation Temperature, Applied Thermal Engineering, vol 26, pp 303–311, 2006 [15] Teng, Y., Wang, R Z., and Wu, J Y., Study of the Fundamentals of Adsorption Systems, Applied Thermal Engineering, vol 17, pp 327–338, 1997 [16] Zhai, X Q., Study on a Solar Integrated Energy System for a Green Building, Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai, 2005 [17] Wang, R Z., and Oliveira, R G., Adsorption Refrigeration—An Efficient Way to Make Good Use of Waste Heat and Solar Energy, Progress in Energy and Combustion Science, vol 32, pp 424–458, 2006 Rogerio G Oliveira is an adjunct professor in the Technology Center of Alegrete, Federal University of Pampa (UNIPAMPA), Brazil He graduated in 1996 as a food engineer in the Food Engineering School (FEA) of the State University of Campinas (UNICAMP), Brazil, and he received his master’s degree in 1999 and his doctoral degree in 2004 at FEA, UNICAMP In 2004 he started his postdoctoral program at Shanghai Jiao Tong University (SJTU), and in 2006 he joined the School of Mechanical Engineering at SJTU as a lecturer He became an associate professor at that school in 2007 His research is related to advanced cycles for solid sorption systems, thermodynamics of sorbent pairs, and heat and mass transfer enhancement of adsorptive beds heat transfer engineering 949 Vivaldo Silveira, Jr., is professor and Vice-Dean of the School of Food Engineering (FEA) at the State University of Campinas (UNICAMP), Brazil He graduated in 1984 as a food engineer in the Fundac¸a˜ o Educacional de Barretos, Brazil, and obtained his master’s degree in 1990 and his doctoral degree in 1995, at FEA, UNICAMP His research interests include cooling systems for food storage, food freezing, adsorption refrigeration, process control, fuzzy logic, and plate heat exchangers Ru Zhu Wang is a professor at Shanghai Jiao Tong University (SJTU) He received his bachelor, master’s, and doctoral degrees at SJTU in 1984, 1987, and 1990, respectively In 1992 he was promoted to associate professor, and in 1994 to professor He has been the director of the Institute of Refrigeration and Cryogenics since 1993 He has published about 300 journal papers, about 180 of them in international journals He wrote five books, which are about refrigeration technologies His major contributions are in the field of adsorption refrigeration, heat transfer to superfluid helium, heat pumps, CCHPs, and solar energy systems He was elected as CheungKong Chaired Professor in 2000 by the Ministry of Education (MOE) of China Currently, he is the president of the Shanghai Society of Refrigeration, the vicechairman of the Chinese Society of Heat Transfer, and he was elected as one of the top one hundred outstanding professors in China Universities by MOE of China in 2007 vol 31 no 11 2010 Heat Transfer Engineering, 31(11):950–956, 2010 Copyright C Taylor and Francis Group, LLC ISSN: 0145-7632 print / 1521-0537 online DOI: 10.1080/01457631003604459 Proof of Concept Car Adsorption Air-Conditioning System Using a Compact Sorption Reactor ROBERT E CRITOPH, STEVEN J METCALF, and ZACHARIE TAMAINOT-TELTO School of Engineering, University of Warwick, Warwick, UK A prototype compact sorption generator using an activated-carbon/ammonia pair based on a plate heat exchanger concept has been designed and built at Warwick University The novel generator has low thermal mass and good heat transfer The heat exchanger uses nickel brazed shims and spacers to create adsorbent layers only mm thick between pairs of liquid flow channels of very low thermal mass The prototype sorption generator manufactured has been evaluated under the European Union (EU) car air-conditioning testing conditions While driven with waste heat from the engine coolant water (at 90◦ C), a pair of the current prototype generators (loaded with about kg carbon in each of two beds) has produced an average cooling power of 1.6 kW with 2-kW peaks INTRODUCTION Adsorption refrigeration and heat pumping devices have the potential to reduce harmful and greenhouse gas emissions (CO, CO2 , NOx , SOx , etc.) and to produce substantial fuel savings The primary energy source for state-of-the-art mobile air conditioning (MAC) systems in cars is mechanical power produced by the engine, to drive the compressor, and electric power to run the fans, which in turn is again derived from the mechanical power from the engine itself The air-conditioning system has a considerable impact on fuel consumption For a B class car on an urban cycle under severe ambient conditions (35◦ C and 60% relative humidity [RH]) it can increase car fuel consumption by up to 70% [1] The CO2 emissions due to the use of MAC range from to 8% on a yearly basis This is equivalent to CO2 emissions from to 10 million tons of CO2 per year in Europe and correspondingly more globally [1] The major technical challenges to developing a sorption system to use the waste heat of a car engine are: Reducing the size sufficiently to fit within the required space This research is supported by the EU TOPMACS project, TST4-CT-2005012394 Address correspondence to Professor Robert E Critoph, School of Engineering, University of Warwick, Warwick, CV4 7AL, UK E-mail R.E.Critoph@warwick.ac.uk Obtaining a sufficient coefficient of performance (COP) to deliver adequate cooling to the vehicle under all driving conditions The intensification of heat transfer within sorption generators has been the focal point of adsorption refrigeration research and development (R&D) at Warwick University, aimed at high power density and COP for both cooling and heating systems The concept of a plate heat exchanger (PLATEX) applied to sorption generators (adsorber/desorbers) for cooling and heatpump applications has been investigated and has proven to be interesting Initial computational modeling of a compact generator using the carbon–ammonia pair reveals an attractive performance: specific cooling power (SCP, the cooling power per unit mass of adsorbent) from kW kg−1 carbon up to 6.5 kW kg−1 carbon and specific heating power 0.250 kW kg−1 carbon up to 2.5 kW kg−1 carbon, with cooling COP varying between 0.5 and 1.2 [2, 3] In the European Union (EU) TOPMACS (thermally operated mobile air conditioning system) project, coordinated by Centro Richerche Fiat, a system is being designed for a class C passenger vehicle Table shows the required cooling power for “normal” use, i.e., transient urban driving cycle use This is actually the most demanding condition for a waste-heat-driven system, because the quantity of waste heat can be limiting Analysis of the heat available from the car’s exhaust and cooling water in 950 R E CRITOPH ET AL 951 Table System performance specification Generator desorption inlet Generator adsorption inlet Condenser inlet Evaporator inlet Heat source flow rate (maximum) Heat sink flow rate (maximum) Flow rate—condenser (liquid) Flow rate—evaporator (liquid) Target performance: Cooling power COP Without auxiliary heater With auxiliary heater 80◦ C 33◦ C 33◦ C 20◦ C 1.44 m3 /h 1.44 m3 /h 0.30 m3 /h 0.30 m3 /h 90◦ C 33◦ C 33◦ C 20◦ C 1.44 m3 /h 1.44 m3 /h 0.30 m3 /h 0.30 m3 /h 1.2 kW 0.52 1.2 kW 0.24 Figure Simplified schematic diagram of system within a car SYSTEM DESIGN both urban and highway driving conditions reveals first that the heat recoverable from the exhaust is too variable and is insufficient to drive a sorption system under urban driving cycles, and second that there will probably be extreme conditions when either storage (of cold or heat) or a backup heat source for the sorption chiller will be needed The chosen solution is to rely on a backup heater using the vehicle’s fuel, which is diesel oil Provided the auxiliary heat is only needed infrequently there will still be considerable fuel savings The 80◦ C driving temperature corresponds to waste heat operation solely and the 90◦ C to waste heat boosted by auxiliary heat In “extreme” conditions (motorway driving at an ambient temperature of 38◦ C), heat is available at 90◦ C and a COP of 0.24 is required This is easily achievable with the system described in this article, and we concentrate on performance under the more onerous “normal” conditions There is also a “cooldown” test condition: water inlet to condenser and adsorber 48◦ C, evaporating temperature 20◦ C, cooling power kW This corresponds to starting the system after the car has been left for a long time in a hot environment A further requirement is that the total system volume should be less than 16 L and mass less than 35 kg Figure Chemically etched shim heat transfer engineering It is well known that for all sorption systems there is a trade-off between the internal thermal regeneration employed (and hence efficiency) and the power density that can be obtained (and hence physical size for a required cooling capacity) In the case of car air conditioning with a driving temperature of no more than 95◦ C and ambient temperature that could have a typical value of 30◦ C there is very little gain to be had from complex many-bed configurations, and a simple two-bed system with mass recovery was selected Figure is a system schematic Valves V1–V4 may be set so that hot water from the engine cooling jacket passes through generator (adsorber/desorber) G1 while water from a fan coil cools generator (adsorber/desorber) G2 toward ambient, or vice versa Operation is straightforward: Generator (adsorber/desorber) G1 is heated by water from the engine cooling circuit, desorbing ammonia, which flows through the check valve V6 to the condenser, where it condenses, rejecting heat to ambient air and then through the refrigerant expansion valve (throttle) V5 to the evaporator, where it boils and chills the water–glycol mixture that cools the vehicle cabin The low-pressure ammonia gas passes through check valve V8 to G2, where it is adsorbed The heat of adsorption is removed by pumped water that is circulated through an air cooled heat exchanger via pump P2 and valves V3, V4 External heating and cooling of the beds stop while valve V10 is briefly opened for mass recovery This allows a rapid transfer of ammonia from G2 to G1 as the pressures equalize The effectively adiabatic desorption from the hot, previously high-pressure bed results in a further reduction in concentration and a corresponding increase of the concentration of the cold, previously low-pressure bed The increased concentration swing over the whole cycle results in both higher cooling power and higher COP Now G2 is heated to desorb ammonia and G1 is cooled to adsorb ammonia as in phase but with G1 and G2 interchanged vol 31 no 11 2010 952 R E CRITOPH ET AL Table Component volumes and masses Adsorbent Reactor heat exchanger Refrigerant Sorption reactor total Condenser Evaporator Auxiliary equipment Total Volume (L) Mass (kg) 12 Not applicable 14 1.2 2.7 19.9 19 22 2 30 Ammonia flows from G2 through V9, condenser, expansion valve V5, evaporator, and check valve V7, to G1 Mass recovery as in step The whole process then repeats as before The most novel parts of the system are the two sorption generators The strict limitations on volume require a very compact solution The generators are similar to plate heat exchangers but with the added constraint that their thermal mass must be as low as possible Computer modeling implies that the conduction path through the carbon (typical conductivity of the order of 0.1 W m−1 K−1 ) should not be more than about mm to ensure low cycle times and adequate SCPs The water-side heat transfer is by means of nominal 0.5-mm square channels with mm pitch Laminar flow in such small channels ensures good heat transfer Taking an approximate Nusselt number of (typical of the three standard boundary conditions of uniform heat flux in flow direction and uniform wall temperature at particular flow cross section, uniform heat flux both in flow direction and around periphery, and uniform wall temperature, from Holman [4]) the water-side heat transfer coefficient based on the projected area of the plate is approximately 3800 W m−2 K−1 The heat flux per unit temperature difference (UA, W K−1 ) value for fluid heat transfer has been calculated at 4200 W K−1 The plates with their water channels were fabricated from pairs of stainlesssteel shims: 0.65 mm thick shims, approximately 150 mm × 150 mm, were chemically etched to create D-shaped channels (Figure 2) which approximated to 0.5 mm square cross section When brazed to 0.25 mm thick plain shims, the pairs form the Table Sorption air conditioning system results Nominal driving Nominal driving temperature 80◦ C temperature 90◦ C Cycle time (s) Generator desorption inlet (◦ C) Generator adsorption inlet (◦ C) Condenser water inlet temperature (◦ C) Evaporator water inlet temperature (◦ C) Chilled water flow rate (L min−1 ) Condenser water flow rate Generator water flow rate Average cooling power (kW) COP 150 82 32 32 20 5 22 1.3 0.23 150 92 32 32 21 5 22 1.6 0.22 heat transfer engineering Figure Reactor with one water manifold required water flow channels Between each of the shim pairs a mm thick U-shaped spacer contains the carbon adsorbent In total, 28 shim pairs, 29 spacers, and end plates are nickel brazed in one operation to form the core of the adsorption reactor (Figure 3) The water manifold is also shown and a close view of the channels through part of the manifold in Figure The whole assembly, in Figure 5, shows the flanges needed to retain the walls against internal ammonia pressures of up to 30 bar The ammonia inlet/outlet connection is in the center of the upper face The threaded tie rods enable the reactor to be disassembled, but a production version would be welded and hermetically sealed The carbon used (Chemviron SRD1352/3) is compacted into the mm slots and initial estimates were that its effective conductivity would be 0.4 W m−1 K−1 The ammonia mass concentration (x) as a function of temperature (T ) and saturation temperature (Tsat ) is given by the Dubinin equation [5] as modified by Critoph [6]: x = x0 exp −k T −1 Tsat n (1) where x0 = 0.4288 is the saturated mass concentration (kg adsorbate/kg adsorbent), k = 12.5626 and n = 1.7366 are constants found by experimental curve fitting to porosity data measured using a Rubotherm magnetic suspension balance, T is the temperature (K), and Tsat is the saturation temperature corresponding to the adsorbate pressure (K) For testing in the laboratory, two sorption generators were constructed in a test rig as shown in Figure Hot and cold water tanks of 120 L capacity were used to provide water for heating or cooling the generators in a controlled fashion, and solenoid valves enabled rapid switching of the hot and cold flows to each generator The ammonia leaving either generator was directed via a check valve to a water-cooled plate condenser, rather than an aircooled condenser as in the vehicle application This was more convenient in the laboratory when trying to maintain steady condensing conditions The liquid ammonia was metered via two solenoid valves into a large flooded evaporator; again, this was convenient for maintaining steady conditions in laboratory vol 31 no 11 2010 R E CRITOPH ET AL Figure assembly 953 Close view of water channels through part of water manifold Figure Laboratory test rig tests The evaporator was used to chill a steady controlled water flow and the temperature drop was monitored by K-type thermocouples As stated earlier, the total system volume should be less than 16 L and mass less than 35 kg Table gives the mass and volumes of the whole system and components The total volume is slightly over target, but achievable in a future version EXPERIMENTAL RESULTS The sorption generator was initially evacuated and then filled with enough ammonia in order to raise the pressure to just above atmospheric, with the condenser and receiver disconnected The generator was then put through several heating and cooling cycles corresponding to pressurization and depressurization of the generator with very little adsorption and desorption The test conditions are: Heating water inlet temperature: 75◦ C • Heating water flow rate: 12 L min−1 • Figure Complete sorption generator heat transfer engineering • • Cooling water inlet temperature: 21◦ C Cooling water flow rate: 12 L min−1 The experimental results of the temperature profiles are presented in Figure Water temperatures were measured by K-type sheathed thermocouples in the water flow at the inlet and outlet of the generator, and the carbon temperature was measured by a mm diameter sheathed K-type thermocouple inserted centrally in the central layer of carbon Two complete cycles of heating and cooling are shown Because the temperatures are measured in the inlet and outlet of the water flow and the flow direction reverses in heating and cooling, at each half cycle the hot inlet temperature becomes the cold outlet temperature and the cold inlet temperature becomes the hot outlet temperature The heating and cooling is extremely rapid: Cooling of the adsorbent from 75◦ C to 30◦ C with 21◦ C cooling water takes just 17 s The heat transfer performance can now be determined from these test results Since no temperature was measured for the stainless-steel shims of the sorption generator, only an overall heat transfer coefficient for the unit as a whole can be determined entirely experimentally However, since the flow within the shims is laminar, the heat transfer coefficient in the fluid can be determined with some confidence Additionally, the heat transfer coefficient in the fluid is an order of magnitude greater Figure Temperature profile during heating/cooling cycles vol 31 no 11 2010 954 Figure results R E CRITOPH ET AL Adsorbent thermal conductivity identified from the experimental than that in the carbon adsorbent Therefore, the heat transfer coefficient in the adsorbent can also be estimated from the experimental results The heat flux per unit temperature difference (UA, W K−1 ) value for fluid heat transfer has been calculated earlier in this article as 4150 W K−1 From this and the overall UA value for the unit (as calculated from the measured heat input to the cooling water and lumping the thermal mass halfway to the center of a carbon layer), the thermal conductivity of the carbon adsorbent can be calculated This is carried out for the first cooling phase of the two cycles as shown in Figure (The second cycle gives substantially the same results.) During the first s period, the heat-exchanger shims are heating rapidly, which distorts the overall UA value of the unit and creates the apparent high adsorbent thermal conductivity When a more stable state is reached and the majority of the heat transfer is to the carbon, a true value for the adsorbent conductivity can be obtained The average value 0.42 W m−1 K−1 was calculated over a 10 s measurement period After this period, the fluid inlet and outlet temperatures become too close to determine an accurate value for the heat output due to measurement noise The experimental value is extremely close to the 0.4 W m−1 K−1 that Figure Temperature and pressure in a cycle with 90◦ C driving temperature heat transfer engineering Figure 10 Cooling power in a cycle with 90◦ C driving temperature has been assumed in previous computational modeling and was based on experimental measurements The prototype was subsequently tested for its cooling production while mounted on the full laboratory air conditioning system test rig driven by heat from water at up to 90◦ C At the modest driving temperature of 90◦ C the benefit of thermal regeneration between the two generators is minimal and only mass recovery was used One generator temperature and pressure cycle with 90◦ C driving temperature is shown in Figure The bed is initially at its maximum temperature of 88◦ C The combination of mass recovery (briefly opening a valve to the low pressure bed) and the sudden influx of cooling water results in a rapid drop in both temperature and pressure to about 55◦ C and bar within about s The lower pressure and temperature result in a greater rate of adsorption of gas from the evaporator, and an increase in the cooling power as can be seen in Figure 10 For the remainder of the half-cycle time of 75 s the cooling rate reduces as the bed temperature approaches the cooling water temperature and the cooling power (proportional to the rate of adsorption) declines from a peak of 2.3 kW to 1.0 kW There is a corresponding slight increase in the evaporating pressure during this period At 75 s the mass recovery operation is carried out, hot water is switched to the bed, and the pressure and temperature rise rapidly for the first 10 s The rate of Figure 11 Cooling power in a cycle with 80◦ C driving temperature vol 31 no 11 2010 R E CRITOPH ET AL 955 Figure 12 Effect of coolant flow rate on the system performance with 90◦ C driving temperature change of temperature decreases as the temperature difference between bed and heating water decreases; the rate of desorption and hence condenser heat rejected falls, corresponding to the slight drop in the condensing pressure The cooling power (Figure 10) from 75 to 150 s corresponds to the vapor from the evaporator going to the other bed The cooling power in both half cycles is not completely identical, but this is due to minor and unintentional differences in the generators, occurring during the manufacturing process The test conditions and results are presented in Table for nominal driving temperatures of 80 and 90◦ C The average cooling production of 1.6 kW with mass recovery corresponds to an SCP of 114 W per liter of generator volume or 800 W kg−1 carbon and a COP of 0.22, which is close to the target value of 0.24 The COP was calculated as the total cooling power integrated over a complete cycle divided by the high-temperature input power to the generator integrated over the cycle It should be remembered that the selection of the adsorbent (Chemviron carbon SRD1352/3) and the design of the generator were based on the maximum cooling production as the primary figure of merit rather than COP Model predictions show that adding thermal enhancement material such as expanded natural graphite to the adsorbent could not only reduce the generator manufacturing cost but also improve the COP by up to a factor of [7] Figure 11 shows the cooling power with a driving temperature of 80◦ C It can be seen that the cooling power drops from 1.6 to 1.26 kW The COP was 0.23, which is below the target of 0.52, and the SCP dropped to 650 W kg−1 carbon The increased COP compared to the 90◦ C driving temperature case is due to the fact that the cycle time had not been optimized The cycle time chosen was based both on simulation and some preliminary experimentation that indicated that it gave reasonable results There will in fact be different optima maximizing power or COP for different conditions Later work will investigate the variation in detail The effect of coolant flow rates through the generator from 0.46 to 1.25 m3 h−1 is presented in Figure 12 It can be seen heat transfer engineering Figure 13 Effect of chilled water inlet temperature that the effect of the flow rate on performance over the range tested is minimal: cooling power ranging between 1.4 and 1.6 kW and with no measurable difference in COP The system should therefore not be significantly affected by the variation in the coolant water flow rate from the engine during the driving cycle The effect of varying the cooling loop inlet temperature to the evaporator is shown in Figure 13 The dramatic effect of decreasing evaporating temperature is evident, as cooling power drops from 1.6 to 1.0 kW and COP drops from 0.22 to 0.15 as the water outlet temperature drops from 15 to 7.5◦ C The approach between the saturation temperature and the water leaving the evaporator is fairly stable at about 2.5◦ C CONCLUSIONS A pair of plate heat exchanger sorption reactors have been built and tested successfully in a laboratory test rig SCPs as high as 800 W per kilogram of adsorbent have been achieved Some, but not all, of the thermal performance criteria have been met or exceeded The current preliminary performance will be improved when operating the system with both mass and heat recovery and with an optimized control strategy NOMENCLATURE x T Tsat ammonia mass concentration (—) temperature (K) saturation temperature (K) vol 31 no 11 2010 956 x0 k n p R E CRITOPH ET AL maximum ammonia mass concentration in Eq (1) constant in Eq (1) constant in Eq (1) absolute pressure (bar) Robert E Critoph is a professor and head of the Sustainable Energy and Engineering Design research group of the School of Engineering at the University of Warwick He obtained his B.Sc in aeronautical engineering from the University of Southampton in 1972, and was awarded the 1972 Royal Aeronautical Society Prize His Ph.D was from the University of Southampton in 1977 and his D.Sc from the University of Warwick in 2007 He has worked in solid adsorption heat pump and refrigeration systems since REFERENCES [1] Mola, S., Centro Richerche Fiat, private communication, 2001 [2] Critoph, R E., and Metcalf, S J., Specific Cooling Power Intensification Limits in Carbon–Ammonia Adsorption Refrigeration Systems, Applied Thermal Engineering, vol 24, no 5–6, pp 661– 679, 2004 [3] Metcalf, S J., Gas-Fired Adsorption Heat Pump for Domestic Gas Boiler Replacement, International Heat Powered Cycles Conference (HPC 2006), paper no 06137, Newcastle, UK, September 2006 [4] Holman, J P., Heat Transfer, 7th ed, in SI Units, McGraw-Hill, Singapore, p 289, 1992 [5] Dubinin, M M., and Astakhov, V A., Description of Adsorption Equilibria of Vapors on Zeolites Over Wide Ranges of Temperature and Pressure, Advances in Chemistry Series, vol 102, pp 69–85, 1970 [6] Critoph, R E., Adsorption Refrigerators and Heat Pumps, in Carbon Materials for Advanced Technologies, ed T D Burchell, Elsevier, Oxford, UK, pp 103–140, 1999 [7] Critoph, R E., Lynch, P., Metcalf, S J., and Tamainot-Telto, Z., Expanded Natural Graphite—Active Carbon Composite for Adsorption Heat Pumps, International Symposium on Innovative Materials for Processes in Energy Systems, Tokyo, paper A044, October 2007 heat transfer engineering 1986 Steven J Metcalf is currently a Ph.D student and research associate at the University of Warwick’s School of Engineering He gained a first class M.Eng degree in mechanical engineering at the university in 2004 and received the I.Mech.E best student award The design of a plate heat exchanger, to which he has made a significant contribution and which was carried out as part of an EU project, has recently been filed with the UK patent office Zacharie Tamainot-Telto graduated from the University of Nancy I in France (M.S.T., 1988), National Polytechnic Institute of Lorraine INPL (M.Sc., 1990), and National Institute of Applied Sciences INSA Lyon (Ph.D., 1993) He joined the School of Engineering at the University of Warwick (UK) in 1994 and has held successively research fellow and senior research fellow positions He has worked on sorption systems applied to heat pumps and air conditioning for several years He has been an assistant professor in refrigeration, heat pumping and energy conservation since 2007 He is a UK chartered engineer and a member of both the Institution of Mechanical Engineers and the Institute of Refrigeration vol 31 no 11 2010 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contamination, an integrated thermostat housing allowing the heater to run dry and the dual tube construction allowing water flow rates to 20 GPM when run in parallel Its non-welded construction minimizes potential leakage, allows highpressure operation and is self-draining when mounted vertically For additional information, call your nearest Watlow representative: Phone: 1+ (800) WATLOW2, 1+ (314) 878-4600; Fax: 1+ (877) 893-1005, 1+ (314) 878-6814; Internet: www.watlow.com; Email: info@watlow.com • Flexible data logging and report generator increases accuracy by automating data collection; • Easy to build, customizable screens automate many tasks with user-defined buttons and simplify monitoring and adjusting of controller parameters, • An alarm manager, which aids in troubleshooting and simplifies alarms through the use of plain-text messages Features such as support for bar code readers and touch screens were designed with industrial users’ needs in mind Process errors are reduced by customizing screens for specific application needs SpecView HMI from Watlow also provides flexibility in data logging, easy-to-use recipe features, remote access options and an historical relay option For more information about SpecView from Watlow, visit www.watlow.com or call 1-800-WATLOW2; 1+ (314) 878-4600; Fax: 1+ (877) 893-1005, 1+ (314) 878-6814 Internet: www.watlow.com; E-mail: info@watlow.com R Watlow Introduces CAST-X 3000 Circulation Heater For Reliable Indirect Heating R Watlow introduces the CAST-X 3000 circulation heater — an economically priced heater offering high flow volume at the required temperature through a single compact product Typical applications include steam generation and superheating for process applications and applications where cleanliness is a major concern These include heating volatile materials in cases where contamination could be a problem such as deionized (DI) water and in food and beverage applications The CAST-X 3000 is also available R R The EZ-ZONE PM Express Panel Mount Controller from Watlow Extends the EZ-ZONE PM Family by Delivering Advanced Control with a Basic User Interface R R Watlow introduces the EZ-ZONE PM Express panel mount controller The EZ-ZONE PM Express fills the need for a PID controller delivering advanced control functionality while having a basic user interface It also extends the breadth of the EZ-ZONE PM family without compromising tuning and control performance The EZ-ZONE PM Express controller features a friendly user interface supported by two menus and a streamlined list of parameters making the product ideally suited for basic applications and user levels The Express menu eliminates complexity and reduces training costs and user errors The EZ-ZONE PM Express controller 957 958 Technical specifications on the MicroSensor Pressure Line can be obtained at http://www.servoflo.com/pressure-sensor-overview/ servoflo-pressure-sensors/microsensor-pressuremeasurement.html For information on all of Servoflo’s product offerings, please visit www.servoflo.com or contact Servoflo Corporation, 75 Allen Street, Lexington, MA 02421 Phone: (781) 862-9572; Fax: (781) 862-9244 comes complete with PID auto-tune for fast, efficient startup Standard bus communications provide easy product configuration via PC communications with EZ-ZONE Configurator as well as connectivity to all other EZ-ZONE products — EZ-ZONE RM, EZ-ZONE ST and EZ-ZONE RUI The controller includes one universal input and the option for up to two outputs and is available in 1/32 or 1/16 DIN panel mount packages The EZ-ZONE Express is the next generation of controllers leveraging the strong legacy of Watlow’s SERIES 93, 935 and SD controllers where easy-to-use features are needed for basic applications It can be ordered as a PID process controller or a dedicated over and under-temperature limit controller For more information on EZ-ZONE PM Express, visit www watlow.com/EZ-ZONE MicroSensor OEM Pressure Sensors for Corrosive and Wet Applications Offered by Servoflo Corporation Servoflo Corporation of Lexington, Massachusetts is pleased to introduce rugged OEM pressure sensors from MicroSensor of China These OEM pressure sensors are designed for rugged, industrial applications Various pressure ranges up to 100 MPa are available, in either gauge, absolute, or differential versions Non-corrosive, isolated construction and stainless steel packages for various media make MicroSensor OEM pressure sensors excellent for embedded applications where ruggedness, anti-corrosiveness, and exposure to media is important The model numbers for this line include the MPM280, MPM281, MPM283, and MDM290 These industrial pressure sensors have an unamplified, linear millivolt output which includes temperature compensation Typical accuracies are 0.3% of full-scale Using an oil-filled piezoresistive pressure sensor with a stainless steel diaphragm, the MicroSensor OEM pressure sensor line is designed for durability in applications such as petroleum refineries, wastewater treatment, industrial HVAC, refrigerants, liquid level measurement and more General pricing for 100 pieces is $25 each for the MPM280, $26– $31 each for MPM281 depending on the pressure range, $27 each for the MPM283, and $35 each for the MDM290 heat transfer engineering PLATINUM CLAD MOLYBDENUM WIRE RESISTS OXIDATION AND CORROSION AT 1,200◦ C A line of platinum clad molybdenum wire that offers performance and cost advantages over solid wire in a wide range of semiconductor and electronics applications is available from Anomet Products, Inc., of Shrewsbury, MA Anomet Platinum Clad Molybdenum Wire provides a low coefficient of thermal expansion and high oxidation and corrosion resistance at up to 1,200◦ C, depending upon the application Available in 0.010 to 0.060 O.D sizes, with cladding from 14 to 26% by weight and 4.5 to 55 microns, depending upon dia., this clad metal wire has a smooth and consistent surface finish Ideal for fabricating feed-throughs in semiconductor fabrication equipment and for making connectors and switch components used in harsh environments, Anomet Platinum Clad Molybdenum wire is offered as wire, rod, and ribbon Metallurgical-bonding assures that this wire provides superior ductility, formability, and weld-ability than electroplated wire, claims the firm Anomet Platinum Clad Molybdenum Wire is priced from $1.95 to $39.95 per ft., depending upon configuration and quantity Literature, samples, and price quotations are available upon request For more information, contact Anomet Products, Inc., Daniel F Lambert, Technical Marketing, 830 Boston Turnpike, Shrewsbury, MA 01545 Phone: (508) 842-3069; Fax: (508) 842-0847; E-mail: dlambert@anometproducts.com; Website: www.anometproducts.com New Line of Valve Positioners Stands Up to Chemical and Food Processing Applications for Complete Valve Automation in Harsh Environments TRIAC’s new YT series of electro-pneumatic positioners is engineered for the harsh environments of chemical and food processing The entire range is ruggedly built for high-performance valve automation applications, and includes corrosion-proof stainless steel and explosion-proof models The YT 1000R explosion-proof electropneumatic positioner is available in both FM- and CSA-approved versions, designed to withstand and contain explosions inside the enclosure, preventing release of flames to the surrounding areas Enhanced process-protection models lock down the system via a fail-freeze function in the event the 4–20mA input signal is lost For applications requiring greater cost economy, the EP line of electro-pneumatic positioners is available in rotary (EPR) or linear (EPL) configurations EP series positioners accept an analog 4–20 mA input signal, and have rugged aluminum diecast enclosures and stainless steel gauges standard These vibration-resistant positioners provide precise calibration with simple span and zero adjustments, are repeatable within ±0.5 percent F.S., and are certified by NEMKO for ATEX and Eex md IIB T5 PP series pneumatic positioners utilize an input signal of 3–15 psi (0.2–1.0 kgf/cm2 ), capable of direct or reverse action with split range available Like the electro-pneumatic line, TRIAC’s pneumatic positioners are available in rotary (PPR) or linear (PPL) versions, and have various orifices available to increase or decrease flow as required Control accessories include single and dual lockup valves, filter regulators, flow and speed controls, and volume boosters Details and specifications for the entire line of TRIAC positioners and accessories are available in a new product brochure, “Pneumatic vol 31 no 11 2010 New Products and Services 959 Figure The YT 2350R electro-pneumatic, smart positioner from TRIAC has a stainless steel enclosure, making it ideal for food processing and other harsh environment duty Figure The entire line of TRIAC positioners are detailed in a new brochure from AT Controls & Electro-Pneumatic Positioners and Controls for Complete Valve Automation.” TRIAC is a division of AT Controls For more information on TRIAC positioners, contact: Ron Ruehlmann, A-T Controls, 11363 Deerfield Rd., Cincinnati OH 45242 Phone: 513-247-5465; Fax: 513247-5462; Email: Rruehlmann@a-tcontrols.com; Website: www.atcontrols.com MOKON INTRODUCES NEWLY REDESIGNED BLOWN FILM AIR COOLERS WITH IMPROVED ENERGY EFFICIENCY Mokon announces their redesigned Blown Film Air Coolers that offer improved performance, energy efficiency and reduced space requirements This new compact design features an air inlet diffuser that creates a more uniform airflow across the cooling coil and decreases delta temperature approach In addition, the leaving air chamber is insulated to reduce condensation while providing the coldest air possible to the air ring The BFC Series offers an increase in blown film productivity, especially in warmer climates or environments where ambient air temperatures rise during the summer, by eliminating production variables in air ring supply, including air temperature, pressure and volume Models are available in sizes from 600 CFM to 7,500 CFM The overall design provides for long life, durability and accurate air ring process control Other features of the Blown Film Air Coolers include: • Powder coated (inside and out) heavy-gauge steel cabinet designed for 35-inch static pressure • Noncorrosive wetted surfaces • 16-inch or 35-inch static pressure blower packages • Permanent cleanable filter • Condensate trap • Drip condensate pan • Bolt-on adjustable legs • Dial thermometers for chilled water inlet, outlet and leaving air • Pre-piped with optional two- or three-way chilled water control valves • Stackable designs are available Figure The explosion-proof YT-1000R electro-pneumatic positioner from TRIAC is FM- and CSA-approved heat transfer engineering Mokon’s circulating liquid heating and chilling equipment are proudly designed and manufactured in the USA For more information, contact Mokon, Buffalo, NY 14207 Phone: 716-876-9951 Fax: 716-874-8048 or visit www.mokon.com vol 31 no 11 2010 Heat Transfer Engineering, 31(11):960–962, 2010 Copyright C Taylor and Francis Group, LLC ISSN: 0145-7632 print / 1521-0537 online DOI: 10.1080/01457631003798939 hot dates HEFAT 2010 7th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics (HEFAT 2010), 19–21 July 2010, Antalya, Turkey Conference website: http://www.hefat.net Conference Organizer: Prof J P Meyer, University of Pretoria, South Africa, e-mail: josua.meyer@up.ac.za The HEFAT2010 Conference will bring together researchers engaged in the application of experimental, analytical or computational heat and mass transfer, fluid flow and thermodynamics Papers will be presented on the following related topics: Fundamentals • Numerical modeling • Fundamentals • Visualization • Heat and mass transfer • Fluid flow • Thermodynamics • Two phase flow • Reaction and combustion • Natural convection • Porous flow • Turbulence • Thermal properties • Measurement technique • Interdisciplinary areas in heat, fluid flow and thermodynamics • Other Applications • Aerodynamics • Aerospace technology • Advanced energy systems • Advanced environmental systems • Biotechnology and medical systems • Boilers • Cogeneration • Cooling towers • Cryogenics • Education • Engines • Enhanced heat transfer • Fluidized beds • Fuel cell systems • Heat exchangers • HVAC • Interactive numerical and experimental methodologies • Manufacturing processes • Material processing • Micro electronic equipment • Micro-electro-mechanical systems • Miniaturized systems for chemistry and life sciences • Nanotechnology • Nuclear • Processes • Renewable energy • Solidification • Suspensions • Turbomachinery • Reactors • Power plants • Other ASME ICNMM10 The ASME ICNMM10 conference (International Conference on Nanochannels, Microchannels and Minichannels) will be held in Montreal during 2–4 August, 2010 in conjunction with the ASME FED2010 conference The web site is www asmeconferences.org/FEDSM2010 PRES 2010 13th International Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction, PRES 2010, 29 August–2 September, 2010, Prague, Czech Republic Joint event with: 19th International Congress of Chemical and Process Engineering 7th European Congress of Chemical Engineering ECCE -7 PRES 2010 is the 13th in the series It was initiated by the late Professor Zdenek Burianec in the framework of CHISA congresses The aim of the PRES conference is to review the latest development and applications of process integration for energy conservation, pollution reduction and related topics Industrial experience of the application of any available method is also welcome Website: www.conferencepres.com President J Klemes, ˇ University of Pannonia, HU P Stehl´ık, VUT Brno, CZ 960 Vice-President F Friedler, University of Pannonia, HU S Pierucci, Politecnico di Milano, IT International Scientific Committee T Bertsson, SE C Bouallou, FR I Bulatov, UK ˇ CZ J Drahos, V Dovi, IT M Emtir, LY D C.Y Foo, MY A Friedl, AT M Georgiadis, GR A Ghajar, USA P Glavic, SI T Gundersen, NO K Hirata, JP D Huisingh, US J Jezowski, PL P Kapustenko, UA E Kenig, DE D Kukulka, USA V Lavric, RO N Lior, US T Majozi, ZA K Matsuda, JP A Meszaros, SK M Narodoslawsky, AT P Oosthuizen, CA S Perry, UK ´ ´ M Picon-N unez MX S Pistikopoulos, UK V Ples¸u, RO L Puigjaner, ES D Reay, UK P Seferlis, GR S K Sikdar, US R Smith, UK K Urbaniec, PL P Varbanov, HU E Worrell, US G Wozny, DE Topics • Energy saving technology • CO2 Kyoto Protocol, sequestration, minimisation • Combined heat & power and combined cycle • Heat exchangers as equipment and integrated items • Process integration for sustainable development • Integration of renewables, biomass and energy conversion technologies • Integrated and multifunctional operations • Operational research and supply chain management • Pulp & paper HOT DATES • Clean technologies - Low emissions technologies • Energy efficient drying technologies • Sustainable processing and production • Waste minimisation, processing and management • Thermal treatment of waste incl waste to energy • Batch processes • Dynamic, flexible and sustainable plant operation • Industrial & experimental studies • Industrial application & optimal design • e-learning, e-teaching and eknowledge • CFD applications in the process intensification • Hydrogen Production from Renewable Resources Publication Policy The selected papers will be published in special thematic issues: • Journal of Cleaner Production • Applied Thermal Engineering • Resources, Conservation and Recycling • ENERGY - The International Journal • Heat Transfer Engineering • Clean Technologies and Environmental Policy Secretariat Hon Loong, Lam (Scientific Secretary) Phone: +36-88-421664 Fax: +44 871 244 774 Email:pres2010.secretary@ gmail.com FUNDAMENTALS OF MICROSCALE HEAT TRANSFER: BOILING, CONDENSATION, SINGLE- AND TWO-PHASE FLOWS A Five Day Short Course in Lausanne, Switzerland (June 7–11, 2010) The 6th Edition of the Fundamentals of Microscale Heat Transfer Course that will be held on the campus of the Swiss Federal Institute of Technology Lausanne (EPFL) located in Lausanne, Switzerland on June 7– 11, 2010 The first edition of this course was given in June 2006 in Lausanne, Switzerland and successfully continued in Lausanne and the US The course provides a comprehensive treatment of both single-phase flow and heat transfer and two-phase flow and heat transfer in microchannels The course is directed to heat transfer specialists in the computer and electronics cooling industries, the automotive and the air-conditioning industries, the aerospace industry, and the micro- and compact heat exchanger industries Furthermore, the course is addressed to Ph.D students and post-doctoral researchers involved in this area of research A team of experts gives all the lectures at the course This is an excellent opportunity to get introduced or updated on the field of microscale heat transfer Any information on the course description, with hotel booking details, campus information, registration form and payment forms (credit card and bank transfer) is posted in internet at: http://termserv casaccia.enea.it/mht course/ Contact Person and Course Coordinator: Prof John R Thome: Laboratory of Heat ´ and Mass Transfer (LTCM), Ecole Polytech´ erale ´ nique Fed de Lausanne (EPFL), CH1015 Lausanne Switzerland - Tel: (+41 21) 693 59 81/82, Fax: (+41 21) 693 59 60; E-mail: john.thome@epfl.ch International Symposium on Innovative Materials for Processes in Energy Systems 2010 (IMPRES2010) – For Fuel Cells, Heat Pumps and Sorption Systems – November 29–December 1, 2010 Furama Riverfront Hotel, Singapore Organizer: IMPRES2010 Organizing Committee, c/o Prof Bidyut Baran Saha, Kyushu University, Japan E-mail: saha@mech.kyushu-u.ac.jp Co-organizers: Faculty of Engineering, National University of Singapore Faculty of Engineering, Kyushu University, Japan School of Mechanical & Aerospace Engineering, Nanyang Technological University, Singapore Sponsor: Mayekawa Manufacturing Co Ltd., Japan Symposium web-site: www.impres2010.org/ CONFERENCE OUTLINE This international symposium welcomes participants of professionals dedicated to theories, experiments, simulations, on the development of functional materials for fuel cells, heat pumps, sorption systems and their applied aspects Attendees will include consulting engineers, design engineers, contractors, architects, manufacturers, researchers and academics The IMPRES held in every three years and this is the second international conference after the successful completion of IMPRES2007 at Kyoto, Japan We heat transfer engineering vol 31 no 11 2010 961 hope to have stimulating and lively discussions in the heart of the city state Singapore Venue Furama Riverfront Singapore 405 Havelock Road Singapore 169699 Tel: +65-67396420, Fax: +65-67327025 http://www.furama.com/riverfront/ Email: salesadmin.riverfront@furama com SCOPE The conference is concerned with the application of novel materials in the field of energy systems with special focus on the gas-solid reaction processes in various energy conversion systems Materials for fuel cells, heat pumps, sorption systems and other energy conversion and storage devices will be discussed Common concerns include material reactivity, heat and mass transfer characteristics, durability, stability under high-temperature and severe conditions and cost This conference aims to bring workers focusing on different aspects of gas-solid reactions in energy conversion and promote an interchange of ideas across subjects TOPICS The following list of topics illustrates the scope of the conference I Materials application Materials for electric energy conversion and storage a) Solid oxide fuel cells b) Polymer electrolyte membrane and direct methanol fuel cells c) Thermoelectric devices d) Hydrogen production, storage and carrier systems e) Batteries and materials for thermal energy conversion and storage f) Chemical heat pumps g) Adsorption heat pumps h) Phase change material heat storage i) Desiccant systems j) Materials Performance k) Improved performance of materials l) Reactivity m) Heat and mass transfer n) Energy storage and conversion density o) Durability in repetitive operation including high temperatures and severe conditions p) Materials design q) Composite materials r) Membrane reactors s) System reliability (corrosion, reactor sealing, reaction selectivity, etc.) t) Others hot dates 962 CALL FOR PAPERS The conference will be conducted in English Extended abstract(s) related to the above topics are invited by May 15, 2010 ABSTRACT SUBMISSION The extended abstract between 300 to 500 words containing the names and addresses of the authors, telephone, fax and e-mail, stating clearly the objective of the work, results and a brief conclusion should be submitted electronically to: www.impres2010.org/ Author(s) should indicate which topic area the paper is addressing Papers those are not suitable for the above topics should be labeled as “other” IMPORTANT: All abstracts and full manuscripts are to be submitted through e-mail by attaching MS Word and PDF files to the following email addresses: Prof B.B Saha (Chairman) saha@mech.kyushu-u.ac.jp and Dr A Chakraborty (Secretary) AChakraborty@ntu.edu.sg • Technical papers will be presented by either orally or posters with short oral presentation for each poster • Selected papers will be published in agreed-upon SCI international journals after reviewing DEADLINES Submission of abstract: May 15, 2010 Notice of acceptance: May 31, 2010 Submission of full manuscript: June 15, 2010 Acceptance notice: July 31, 2010 Final manuscript submission: September 15, 2010 CONFERENCE FEE* Registration Fees (On or before September 15, 2010): Delegate: S$ 750 Student: S$ 450 Accompanied person**: S$ 300 Late Registration (including onsite registration): Delegate: S$ 850 Student: S$ 550 Conference proceedings in book and CD-ROM, reception party, conference banquet, lunches and coffee breaks are included in the registration fees *Each paper requires registration of at least one participant before September 15, 2010, who will present the paper during the conference **Accompanying person will not receive conference proceedings GENERAL ORGANIZING COMMITTEE Chairman Prof Bidyut Baran Saha Kyushu University, Japan E-mail: saha@mech.kyushu-u.ac.jp General Secretary Dr Anutosh Chakraborty Nanyang Technological University, Singapore E-mail: AChakraborty@ntu.edu.sg Accounting Coordinator Mr Kyaw Thu National University of Singapore, Singapore E-mail: mpekt@nus.edu.sg LOCAL ORGANIZING COMMITTEE Chairman Prof Kim Choon Ng National University of Singapore, Singapore E-mail: mpengkc@nus.edu.sg Executive Committee Members Prof Arun Majumder National University of Singapore, Singapore Prof Cristopher Yap National University of Singapore, Singapore Dr Kandadai Srinivasan National University of Singapore, Singapore Prof Fei Duan Nanyang Technological University, Singapore Dr Hideharu Yanagi National University of Singapore, Singapore Dr Abdul Halim National University of Singapore, Singapore INTERNATIONAL SCIENTIFIC COMMITTEE MEMBERS Prof Yukitaka Kato (Chairman, IMPRES2007) Tokyo Institute of Technology, Japan Prof Lua Aik Chong Nanyang Technological University, Singapore Prof Afshin J Ghajar Oklahoma State University, USA Prof Srinivasa Murthy Indian Institute of Technology, Madras, India Prof Seong Ho Yoon Kyushu University, Japan Prof Atsushi Akisawa Tokyo Univ of Agr & Tech., Japan Prof Yasuyuki Takata Kyushu University, Japan Prof Shigeru Koyama Kyushu University, Japan Prof Felix Ziegler Technische Universitat Berlin, Germany Dr Elisa Boelman European Commission, Brussels Prof Min-Soo Kim Seoul National University Prof Hideo Mori Kyushu University, Japan Prof Robert E Critoph Warwick University, UK heat transfer engineering vol 31 no 11 2010 Prof Yuriya I Aristov Boreskov Institute of Catalysis, Novosibirsk, Russia Prof Yong Tae Kang Kung Hee University, Korea Dr Belal Dawoud Viessmann GmbH & Co KG, Germany Prof Ruzhu Wang Shanghai Jiao Tong University, China Prof Pradip Dutta Indian Institute of Science, India Dr Uli Jacob dr Jakob Energy Research, Germany Dr Keiko Fujioka Functional Fluids Co Ltd., Japan Prof Kuenman Cho Sungkyunkwan University, Korea Prof Akio Kodama Kanazawa University, Japan Prof Agami T Reddy Arizona State University, USA Prof Mike Tierney Bristol University, UK ATTRACTIVE PLACES IN SINGAPORE Sentosa Nature beckons everywhere on Sentosa, where a lazy holiday of sun, sand and sea awaits one and all The fun paradise of Singapore is MERLION standing 37 m tall The MERLION (the shape of a lion’s head and the body of a fish) offers vantage viewing point of Sentosa, Singapore’s city skyline and the surrounding islands Jurong Bird Park Jurong Bird Park is a 20.2 hectare openconcept park It is the largest in the Asia Pacific and one of the finest bird parks in the world Jurong Bird Park, collection of more than 8,000 birds from 600 species, offers visitors an experience that is entertaining and educational Clark Quay Clark Quay features five blocks of restored warehouses and is the home to hip entertainment, dining outlets and shops of all kinds In the evening, theme pubs and bars become alive with classic rock, hard rock, the blues and music from the 60s