Heat Transfer Handbook part 111 pdf

BOOKCOMP, Inc. — John Wiley & Sons / Page 1097 / 2nd Proofs / Heat Transfer Handbook / Bejan ACTIVE TECHNIQUES 1097 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1097], (69) Lines: 1359 to 1368 ——— 0.0pt PgVar ——— Normal Page PgEnds: T E X [1097], (69) to 3% by weight) of 1-pentanol in saturated pool boiling of water. In another study, van Stralen (1970) reports up to 80% improvement in the film boiling coefficient in a 4 : 1 weight percent mixture of 2-butanone and water. Bergles and Scarola (1966) and Pabisz and Bergles (1997) have considered subcooled flow boiling of water [a 1-pentanol (2.2% by weight) mixture] and found a distinct reduction in CHF at low subcooling. Contrarily, with the addition of a surfactant to seawater, the overall heat transfer coefficient was found to be doubled in vertical upflow boiling in a desalination application. 14.9 ACTIVE TECHNIQUES A variety of active techniques, including mechanical aids (stirring, surface scrap- ing, and rotating surfaces), surface vibration, fluid vibration, electrostatic (electric and magnetic) fields, injection, suction, and jet impingement, have been investi- gated in the literature (Bergles, 1998). As indicated earlier, all of these methods and devices require the input of external power to promote the desired enhancement, which should be accounted for appropriately when evaluating the improved thermal– hydraulic performance. For stirring and surface scraping devices, Uhl (1970) and Hagge and Junkhan (1974) provide early reviews and the applications include both single-phase and boiling heat transfer. Rotating surfaces commonly preexist in cooling of rotating electrical machinery and gas turbine rotor blades, and substantial enhancement (of up to 350%) in heat transfer coefficients for laminar flows in straight tubes rotating around their own axis or a parallel axis have been reported (Mori and Nakayama, 1967c; McElhiney and Preckshot, 1977; Vidyanidhi et al., 1977). Tang and McDonald (1971) have reported that with high-speed rotation of heated cylinders in saturated pools, the convective coefficients are so high that boiling canbesuppressed. Enhanced steam condensation on a rotating vertical cylinder has been documented by Nicol and Gacesa (1970). In most recent studies, however, compound use of surface rotation has generally been considered, with some other technique for enhanced cooling of gas turbine blades (Eliades et al., 2001; Hwang et al., 2001). For almost three decades, starting in the late 1930s, much work was done on induc- ing enhanced heat or mass transfer by effecting sufficiently intense surface vibrations or oscillations, particularly in the free convection mode (Martinelli and Boelter, 1939; McAdams, 1954; Fand and Peebles, 1962; Lemlich and Rao, 1965; Bergles, 1969). Depending on oscillation amplitude-to-tube diameter ratios and vibration Reynolds numbers, up to 20-fold increases in heat transfer coefficients compared with those for stationery tubes have been reported (Bergles, 1998). Substantial improvements in heat transfer induced by heated surface vibrations in forced-convection applications have also been recorded. A caveat on using this technique is thatcavitation becomes a prob- lem when the vibration intensity becomes too large, which causes a sharp degradation of heat transfer. Hsieh and Marsters (1973) have further extended this method to an array of five horizontal cylinders and reported up to a 54% increase in the average heat transfer coefficients at the highest surface vibration intensity. Based on experiments BOOKCOMP, Inc. — John Wiley & Sons / Page 1098 / 2nd Proofs / Heat Transfer Handbook / Bejan 1098 HEAT TRANSFER ENHANCEMENT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1098], (70) Lines: 1368 to 1372 ——— 0.0pt PgVar ——— Normal Page PgEnds: T E X [1098], (70) with saturated as well as subcooled boiling, Bergles (1969) has shown that heater- surface vibrations have little effect on the heat transfer. However, the CHF increased by a maximum of about 10% at an average velocity of 0.25 m/s. Other experiments have confirmed that fully developed boiling is essentially unaffected by vibration (McQuiston and Parker, 1967; Price and Parker, 1967; Fuls and Geiger, 1970). In a few studies (e.g., Brodov et al., 1977), up to 10 to 15% enhancement in the conden- sation heat transfer coefficients have been obtained in a vibrating horizontal tube. There has been considerable research on the use of fluid vibrations (or pulsations) to enhance heat transfer, particularly the application of acoustic fields (Bergles, 1998). Improvements of 100 to 200% over natural convection heat transfer coefficients in air were obtained by Sprott et al. (1960), Fand and Kaye (1961), and Lee and Richard- son (1965) by generating intense sound fields and directing them transversely to a horizontal heated cylinder, although there could be large circumferential variations in the local heat transfer coefficients at these acoustic vibration intensities (Fand et al., 1962). In liquids, ultrasonic frequencies may be used to the desired acoustic streaming (about 1 MHz produces a type of streaming called crystal wind), although these intensities may still be high enough to cause cavitation. Robinson et al. (1958), Zhukauskas et al. (1961), Larson and London (1962), Fand (1965), and Li and Parker (1967), among others, report 30 to 45% increases in free convection heat transfer by means of sonic and ultrasonic vibrations. In his experiments with high surface temper- atures, where it was possible to achieve cavitation, Bergles (1964) found that lower- frequency vibrations (80 Hz) provided up to 50% enhancement in the heat transfer. Furthermore, while ultrasonic vibrations appear to promote no improvements in nu- cleate pool boiling (Wong and Chon, 1969), they enhance vapor removal and lend to an increase in CHF by almost 50% (Ornatskii and Shcherbakov, 1959). Internal duct flow boiling is also reported to be unaffected irrespective of the ultrasonic vibration intensity (Bergles and Newell, 1965). Mathewson and Smith (1963) investigated the effects of up to a 176-dB acoustic field with frequencies in the range 50 to 330 Hz and found laminar film condensation coefficients for isopropanol to be enhanced by about 60% at low vapor flow rates. The use of electric and magnetic fields to enhance heat transfer, or electrohydro- dynamic (EHD) enhancement, has received considerable attention in the literature for more than four decades. Several recent reviews of its applications and extended dis- cussion of the fundamental electromagnetic field effects on heat transport have been published (Jones, 1978; Viskanta, 1985; Poulter and Allen, 1986; Yabe, 1991). Much of this work has focused on improvement of single-phase heat transfer, where the technique has been shown to be particularly effective (Webb, 1994; Bergles, 1998; Nelson et al., 2000). In laminar forced convection in transformer oil, several early studies have shown at least 100% enhancement in the heat transfer (Savkar, 1971; Newton andAllen,1977);it may be pointed out here that electric transformers provide a preexisting electromagnetic field. More recent work has addressed the application of electric fields with its attendant corona discharge (or corona wind) for enhancing air- and gas-flow heat transfer in tubular exchangers (Davidson et al., 1987; Ohadi et al., 1994; Nelson et al., 2000). EHD use has been also extended to phase-changer sys- tems, where enhancement of nucleate boiling and CHF as well as film condensation BOOKCOMP, Inc. — John Wiley & Sons / Page 1099 / 2nd Proofs / Heat Transfer Handbook / Bejan COMPOUND ENHANCEMENT 1099 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1099], (71) Lines: 1372 to 1386 ——— -0.03pt PgVar ——— Normal Page PgEnds: T E X [1099], (71) have been investigated (Choi, 1961; Velkoff and Miller, 1965; Cooper, 1990; Ogata and Yabe, 1993; Xu et al., 1995; Chen and Liu, 1999; Chu et al., 2000). Attempts to model the electric field effects on boiling heat transfer analytically and/or com- putationally have also been reported in the literature (Karayiannis and Xu, 1998a,b). For some other novel applications, a U.S. patent (Blomgren and Blomgren, 1972) describes the cooling of cutting tools by point electrodes, and a few proposals have considered compound use of electric fields with finned surfaces to improve the single- phase heat dissipation (Reynolds and Holmes, 1976), and condensation heat transfer (Chu et al., 2001). Jet impingement techniques have gained considerable recent interest, particu- larly for their significant potential in microelectronic cooling, MEMS, and other mi- croscale devices (Chu and Chrysler, 1998; Behnia et al., 2001; Honma et al., 2001; Amon et al., 2001), gas-turbine blade cooling (Ekkad et al., 2000; Hwang and Chang, 2000; Cornaro et al., 2001), and manufacturing, drying, heat treating, and quenching applications (Viskanta, 1998; Hall et al., 2001a,b). These applications involve both single-phase and boiling heat transfer, and jet impingement techniques have been found to enhance the heat transfer considerably. Strategies to develop optimum arrays of jets for specific duties (San and Lai, 2001) and computational modeling (Kumagai et al., 2002) have also been proposed in the literature. 14.10 COMPOUND ENHANCEMENT As Bergles (2000) has pointed out, “compound techniques offer a way to further elevate heat transfer coefficients,” and this area of enhancement technology holds much promise for future development. Indications of their emerging development and growth are evident in a recent survey of the 2001 literature (Manglik and Bergles, 2002b). Conceptually, with compound techniques, heat transfer coefficients can be increased above each of the techniques acting alone. A variety of combinations for two or more enhancement methods or devices have been considered, and some rep- resentative examples are discussed in this section. Perhaps the most attractive potential for compound technique use are offered by systems where one form of enhancement preexists “naturally.” Good examples are rotating systems, which include rotor windings of large turbogenerators or electric motors, and gas-turbine blades, among others. A few different passive techniques have been applied in rotating tubes and ducts in the literature. Muralidhar Rao and Sastri (1995) have used twisted-tape inserts in a tube that rotates around a parallel axis (to simulate the coolant channel of an electric machine), and their results for laminar flow of air are presented in Fig. 14.42. The Nusselt number is seen to increase with rotational speed (J a ) and is greater than that predicted for a stationary tube with a twisted-tape insert of y = 5; the latter, in turn, has been found to be higher than empty rotating tube performance. Similarly, in rotating U-bend flat or rectangular ducts that simulate internal flow passages of a gas-turbine airfoil, structured roughness or ribs have been considered to enhance integral blade cooling (Hwang et al., 2001; Iacovides et al., 2001; Lin et al., 2001; Murata and Mochizuki, 2001). In another example, both BOOKCOMP, Inc. — John Wiley & Sons / Page 1100 / 2nd Proofs / Heat Transfer Handbook / Bejan 1100 HEAT TRANSFER ENHANCEMENT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1100], (72) Lines: 1386 to 1390 ——— 0.42099pt PgVar ——— Normal Page PgEnds: T E X [1100], (72) Figure 14.42 Effect of tube rotational speed (J a ) on Nusselt number enhancement in laminar flow heat transfer in a circular tube with a twisted-tape insert. (From Muralidhar Rao and Sastri, 1995.) ribbed roughness and vortex generators have been used in a two-pass rotating duct (Acharya et al., 2000; Eliades et al., 2001). Many different compound schemes involving twisted-tape inserts have been con- sidered for single-phase forced-convective and boiling applications (Manglik and Bergles, 2002a). For single-phase flows, besides the rotating tube example discussed previously (Rao, 1983; Muralidhar Rao and Sastri, 1995), experimental data for rough tubes or ribbed ducts with twisted-tape inserts (Bergles et al., 1969; Shivkumar and Raja Rao, 1988; Zhang et al., 2000; Zimparov, 2001), and internally finned tubes with twisted-tape inserts (Van Rooyen and Kr ¨ oger, 1978; Usui et al, 1984; Zhou et al., 1990) are available. Additionally, Wu et al. (2000) have tested the performance of decaying swirl flows (produced by inlet axial vanes) in spirally corrugated tubes. The heat transfer coefficients are generally enhanced to a greater extent than that with each individual technique in these cases. However, an interesting forced convection boiling study by Pabisz and Bergles (1996) reports a rather surprising consequence of using twisted-tape inserts along with 1-pentanol additive to water ina3to4%mixture by weight. Here the CHF was found to be reduced below that with the twisted tape and pure water. BOOKCOMP, Inc. — John Wiley & Sons / Page 1101 / 2nd Proofs / Heat Transfer Handbook / Bejan NOMENCLATURE 1101 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1101], (73) Lines: 1390 to 1500 ——— 0.20352pt PgVar ——— Normal Page PgEnds: T E X [1101], (73) Some other representative examples of promising compound enhancement tech- niques for varied practical applications that have been proposed in the literature are as follows: • Corrugated (rough) tube with a hydrophobic coating (treated surface) to promote dropwise condensation of steam (Das et al., 2000) • Application of EHD fields in poolboiling of refrigerant R-134a from microfinned and treated tubes (Darabi et al, 2000) • Single-phase mass transfer enhancement in grooved (finned) channel with flow pulsations (Nishimura et al., 1998), and heat transfer in an acoustically excited flow field over a rough cylinder (Kryukov and Boykov, 1973) • Gas–solid suspension flows in an electric field (Min and Chao, 1966; Elsdon and Shearer, 1977; Bologa et al., 1985) • Fluidized-bed (air-particle suspension) heat transfer with airflow pulsations (Bhattacharya and Harrison, 1976) and across finned tubes (Bartel and Genetti, 1973) • Surfactant additive for seawater evaporation in spirally corrugated or doubly fluted (rough surface) tubes (Sephton, 1971, 1975) Again, as in the CHF reduction case with twisted-tape inserts as a volatile liquid additive to water (Pabisz and Bergles, 1996), another surprise in compound enhance- ment is reported by Masliyah and Nandakumar (1977). Their computational results revealed that average Nu for internally finned coiled tubes was lower than that in plain coiled tubes for the same flow conditions. Bergles (2000) refers to another example where there was reduction in average single-phase heat transfer coefficients ina coiled tube with pulsating flow (fluid vibration) compared with coiled tube performance in steady flow. Finally, issues relating to the performance of enhancement techniques under foul- ing conditions remain relatively unresolved (Bergles, 2000; Somerscales and Bergles, 1997). Several instances of enhancement techniques acting to mitigate fouling are cited. Many patents for different devices also claim that their use not only enhances heat (and/or mass) transfer, but also reduces fouling (Bergles et al., 1991; Somerscales and Bergles, 1997). NOMENCLATURE Roman Letter Symbols A heat transfer surface area, m 2 A c area of flow cross section, m 2 A e effective heat transfer surface area, m 2 A f heat transfer surface area of fins, m 2 A r area of unfinned (or root) portion of tube, m 2 C concentration, wppm BOOKCOMP, Inc. — John Wiley & Sons / Page 1102 / 2nd Proofs / Heat Transfer Handbook / Bejan 1102 HEAT TRANSFER ENHANCEMENT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1102], (74) Lines: 1500 to 1500 ——— 0.32384pt PgVar ——— Normal Page PgEnds: T E X [1102], (74) c p specific heat of fluid, J/kg · K c s correction factor, dimensionless c.m.c. critical micelle concentration of a surfactant at equilibrium conditions, wppm D outside diameter of tube, m D o outside diameter of circular finned tube, m D r root diameter of externally finned tube, m De Dean number, dimensionless d inside or envelope tube diameter, m d h hydraulic diameter, m [ = 4A c /P w ] d i tube inside or envelope diameter, m Eu Euler number, dimensionless pressure drop e roughness or rib height, m f Fanning friction factor, dimensionless G mass flux kg/m 2 · s [ =˙m/A c ] Gr Grashof number, dimensionless  = gρ 2 d 3 β∆T w /µ 2  Gz Graetz number, dimensionless  =˙mc p /kL  H 180° tape-twist pitch, m pitch of a helical coil, m He helical number, dimensionless h heat transfer coefficient, W/m 2 · K offset strip fin height, m h f fin height, m i lg specific enthalpy of vaporization, J/kg J a tube rotation speed, dimensionless j Colburn factor, dimensionless  = St ·Pr 2/3 = Nu/Re · Pr 1/3  k thermal conductivity, W/m ·K L tube length, m L h heated length of tube, m L s effective swirl flow length, m L th thermal entrance length of duct, m l offset length in offset strip fin cores, m ˙m mass flow rate, kg/s N number of tubes, dimensionless N L number of tube rows in flow direction in a tube bundle, dimensionless n number of fins, dimensionless Nu Nusselt number, dimensionless Nu z axially local Nusselt number, dimensionless P pumping power, N · m/s P w wetted perimeter, m p pressure, N/m 2 pitch, m p f fin pitch, dimensionless BOOKCOMP, Inc. — John Wiley & Sons / Page 1103 / 2nd Proofs / Heat Transfer Handbook / Bejan NOMENCLATURE 1103 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1103], (75) Lines: 1500 to 1519 ——— -0.47429pt PgVar ——— Normal Page PgEnds: T E X [1103], (75) ∆p pressure drop, N/m 2 Pr Prandtl number, dimensionless  = µc p /k  Q heat transfer rate, W q  heat flux, W/m 2 [ = q/A ] R curvature radius of a curved tube or zero-pitch coil, m R c radius of curvature of a helical boil, m Ra Rayleigh number, dimensionless [ = Gr ·Pr ] Ra ∗ modified Rayleigh number based on the wall heat flux, dimensionless Re Reynolds number, dimensionless empty tube Reynolds number, [ = 4 ˙m/πdρµ ] Re a tape-partitioned tube Reynolds number, dimensionless [ = Gd/µ ] S L longitudinal pitch of tube centers in a tube bundle, m S T transverse pitch of tube centers in a tube bundle, m St Stanton number, dimensionless [ Nu/Re · Pr ] Sw swirl parameter, dimensionless s interfin separation in offset strip fins, m average spacing between adjacent fins, m T temperature, K ∆T i approach temperature difference, K ∆T lm log-mean temperature difference, K t fin thickness, m U mean axial velocity, m/s overall heat transfer coefficient, W/m 2 · K UHF uniform wall heat flux boundary condition UWT uniform wall temperature boundary condition V a mean axial velocity in a tape-partioned tube, [ = G/ρ ] , m/s V s swirl velocity, m/s w width of twisted-tape insert, m x average mass quality of vapor–liquid flow, dimensionless y twist ratio of a twisted-tape insert, dimensionless [ = H/d ] Greek Letter Symbols α spiral fin helix angle, deg aspect ratio of the flow cross section of noncircular duct (height/width), dimensionless aspect ratio for offset strip fin channel, dimensionless [ = s/h ] β wavy plate fin density factor, dimensionless  = fin separation/waviness depth  γ aspect ratio of corrugated plate or fin waviness, dimensionless  = waviness depth/pitch  ratio of fin thickness to fin separation of offset strip fins, dimensionless [ = t/s ] BOOKCOMP, Inc. — John Wiley & Sons / Page 1104 / 2nd Proofs / Heat Transfer Handbook / Bejan 1104 HEAT TRANSFER ENHANCEMENT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1104], (76) Lines: 1519 to 1566 ——— -3.25645pt PgVar ——— Custom Page (6.0pt) PgEnds: T E X [1104], (76) δ ratio of fin thickness and fin offset length, dimensionless [ = t/l ] thickness of a twisted tape, m ε fin surface extension ratio, dimensionless [ = total surface area/bare tube surface area ] η f fin efficiency, dimensionless µ dynamic viscosity, N/m 2 · s ρ fluid density, kg/m 3 Subscripts b bulk or mean temperature conditions cr critical heat flux e exit conditions g gas or vapor state H UHF thermal boundary condition h hydraulic diameter i inlet condition inner surface inside (envelope) diameter iso adiabatic isothermal conditions l liquid state m bulk mean or average quantity length-averaged quantity max maximum value o smooth tube, channel, or surface s twisted-tape-induced swirl flows sat saturation condition or the wall superheat st a straight tube sub subcooled condition subcooling T UWT thermal boundary condition tr laminar-turbulent transition flow regime w wall condition heat transfer surface ∞ free stream conditions REFERENCES Acharya, N., Sen, M., and Chang, H C. (1994). Thermal Entrance Length and Nusselt Num- bers in Coiled Tubes, Int. J. Heat Mass Transfer, 37(2), 336–340. Acharya, S., Hibbs, R. G., Chen, Y., and Nikitopoulos, D. E. (2000). Mass/Heat Transfer in a Ribbed Passage with Cylindrical Vortex Generators: The Effect of Generator-Rib Spacing, J. Heat Transfer, 122(4), 641–652. Achenbach, E. (1977). The Effect of Surface Roughness on the Heat Transfer from a Circular Cylinder to the Cross Flow of Air, Int. J. Heat Mass Transfer, 20, 359–369. BOOKCOMP, Inc. — John Wiley & Sons / Page 1105 / 2nd Proofs / Heat Transfer Handbook / Bejan REFERENCES 1105 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 [1105], (77) Lines: 1566 to 1603 ——— * 16.0pt PgVar ——— Custom Page (6.0pt) PgEnds: T E X [1105], (77) Ackerman, J. W. (1970). Pseudoboiling Heat Transfer to Supercritical Pressure Water in Smooth and Ribbed Tubes, J. Heat Transfer, 92, 490–498. Adamek, T. A. 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Experiments on Pool Boiling Heat Transfer, Int. J. Heat Mass Transfer, 5, 985–999. Bergles, A. E. (1964). The Influence of Flow Vibrations on Forced-Convection Heat Transfer, J. Heat Transfer, 86, 559–560. Bergles, A. E. (1969). The Influence of Heated-Surface Vibration on Pool Boiling, J. Heat Transfer, 91, 152–154. Bergles, A. E. (1986). Evolution of Cooling Technology for Electrical, Electronic, and Micro- electronic Equipment, Heat Transfer Eng., 7(3–4), 97–106. Bergles, A. E. (1990). Electronic and Microelectronic Equipment, Hemisphere Publishing, New York. Bergles, A. E. (1997). Enhancement of Pool Boiling, Int. J. Refrig., 20(8), 545–551. Bergles, A. E. (1998). Techniques to Enhance Heat Transfer, in Handbook of Heat Transfer, 3rd ed., (Rohsenow W. M., Hartnett, J. P., and Cho, Y. I., eds.), McGraw-Hill, New York, Chap. 11. Bergles, A. E. (1999). The Imperative to Enhance Heat Transfer, Heat Transfer Enhancement of Heat Exchangers (Kakac¸, S., Bergles, A. E., Mayinger, F., and Y ¨ uncii, H., eds.) Kluwer, Dordrecht, The Netherlands, 13–29. Bergles, A. E. (2000). New Frontiers in Enhanced Heat Transfer, in Advances in Enhanced Heat Transfer, 2000, (Manglik, R. M., Ravigururijan, T. S., Muley, A., Papar, A. R., and Kim, J., eds.), ASME, New York, pp. 1–8. Bergles, A. E., and Champagne, P. (1999). Novel Variable Roughness Technique to Enhance, on Demand, Heat Transfer in a Single-Phase Heat Exchanger, provisional U.S. patent application 60/144,563, July 16. Bergles, A. E., and Chyu, M. C. (1982). Characteristics of Nucleate Pool Boiling from Porous Metallic Coatings, J. Heat Transfer, 104, 279–285. Bergles, A. E., and Newell, P. H., Jr. (1965). The Influence of Ultrasonic Vibrations on Heat Transfer to Water Flowing in Annuli, Int. J. Heat Mass Transfer, 8, 1273–1280. Bergles, A. E., and Scarola, L. S. (1966). Effect of a Volatile Additive on the Critical Heat Flux for Surface Boiling of Water in Tubes, Chem. Eng. Sci., 21, 721–723. Bergles, A. E., and Thompson, W. G., Jr. (1970). The Relationship of Quench Data to Steady- State Pool Boiling Data, Int. J. Heat Mass Transfer, 13, 55–68. Bergles, A. E., Lee, R. A., and Mikic, B. B. (1969). Heat Transfer in Rough Tubes with Tape- Generated Swirl Flow, J. Heat Transfer, 91, 443–445. Bergles, A. E., Fuller, W. D., and Hynek, S. J. (1971). Dispersed Flow Film Boiling of Nitrogen with Swirl Flow, Int. J. Heat Mass Transfer, 14(9), 1343–1354. Bergles, A. E., Blumenkrantz, A. R., and Taborek, J. (1974a). Performance Evaluation Criteria for Enhanced Heat Transfer Surfaces, in Heat Transfer 1974 (Proc. 5th International Heat Transfer Conference), Vol. 2, JSME, Tokyo, pp. 234–238. Bergles, A. E., Bunn, R. L., and Junkhan, G. H. (1974b). Extended Performance Evaluation Criteria for Enhanced Heat Transfer Surfaces, Lett. Heat Mass Transfer, 1, 113–120. . Vibrations on Forced-Convection Heat Transfer, J. Heat Transfer, 86, 559–560. Bergles, A. E. (1969). The Influence of Heated-Surface Vibration on Pool Boiling, J. Heat Transfer, 91, 152–154. Bergles,. (1979). Heat Transfer from Freon-113, Ethyl Alcohol and Water with Screen Wicks, Heat Transfer Sov. Res., 11(1), 92–100. Austen, D. S., and Soliman, H. M. (1988). Laminar Flow and Heat Transfer. Spacing, J. Heat Transfer, 122(4), 641–652. Achenbach, E. (1977). The Effect of Surface Roughness on the Heat Transfer from a Circular Cylinder to the Cross Flow of Air, Int. J. Heat Mass Transfer,