BỘ GIÁO DỤC VÀ ĐÀO TẠO TRƯỜNG ĐẠI HỌC SƯ PHẠM KỸ THUẬT THÀNH PHỐ HỒ CHÍ MINH LUẬN VĂN THẠC SĨ LƯƠNG PHẠM TRUNG KHÁNH NGHIÊN CỨU CÁC ĐẶC TÍNH HOẠT ĐỘNG CỦA CÁC ĐIỆN CỰC TRONG PIN NHIÊN LIỆU OXIT RẮN (SOFC) BẰNG PHƯƠNG PHÁP MÔ PHỎNG SỐ NGÀNH: KỸ THUẬT NHIỆT – 8520115 SKC007246 Tp Hồ Chí Minh, tháng 05/2021 BỘ GIÁO DỤC VÀ ĐÀO TẠO TRƯỜNG ĐẠI HỌC SƯ PHẠM KỸ THUẬT THÀNH PHỐ HỒ CHÍ MINH LUẬN VĂN THẠC SĨ LƯƠNG PHẠM TRUNG KHÁNH NGHIÊN CỨU CÁC ĐẶC TÍNH HOẠT ĐỘNG CỦA CÁC ĐIỆN CỰC TRONG PIN NHIÊN LIỆU OXIT RẮN (SOFC) BẰNG PHƯƠNG PHÁP MÔ PHỎNG SỐ NGÀNH : KỸ THUẬT NHIỆT – 8520115 TP.Hồ Chí Minh, tháng 05/2021 BỘ GIÁO DỤC VÀ ĐÀO TẠO TRƯỜNG ĐẠI HỌC SƯ PHẠM KỸ THUẬT THÀNH PHỐ HỒ CHÍ MINH LUẬN VĂN THẠC SĨ LƯƠNG PHẠM TRUNG KHÁNH NGHIÊN CỨU CÁC ĐẶC TÍNH HOẠT ĐỘNG CỦA CÁC ĐIỆN CỰC TRONG PIN NHIÊN LIỆU OXIT RẮN (SOFC) BẰNG PHƯƠNG PHÁP MÔ PHỎNG SỐ NGÀNH : KỸ THUẬT NHIỆT – 8520115 Hướng dẫn khóa học: TS NGUYỄN XUÂN VIÊN TP.Hồ Chí Minh, tháng 05/2021 102 [29] Xuan–Vien Nguyen, Guo–Bin Jung, Shih–Hung Chan, Chia–Chen Yeh, Jyun–Wei Yu Improvement on the design and fabrication of planar SOFCs with anode–supported cells based on modified button cells, To appear in Renewable Energy 2017.03.070 [30] Lê Thanh Long, Phạm Quang Trung Khoa Cơ khí - Trường Đại học Bách Khoa TP HCM nghiên cứu thiết kế mơ hình hệ thống pin nhiên liện, hội nghị khcn toàn quốc khí - động lực, 2017, PP.274-281 [31] Tiến sĩ Nguyễn Mạnh Tuấn, Phân viện Vật lý TP.HCM Kết nghiên cứu pin nhiên liệu pin sử dụng nhiên liệu cồn methanol thay cho nhiên liệu hydro, sở khoa học công nghệ tp-hcm trung tâm thông tin khoa học công nghệ, 2004, PP.1-5 [32] Tiến sĩ Nguyễn Chánh Khê Chế tạo màng chuyển hóa proton cho pin nhiên liệu Trung tâm Nghiên cứu Phát triển – Khu công nghệ cao TP.HCM, 2055, PP.36-49 [33] PGS.TS Nguyễn Mạnh Tuấn – Phó Viện Trưởng – Viện Vật Lý Thành phố Hồ Chí Minh, nghiên cứu chế tạo pin nhiên liệu – triển vọng xu hướng nhiên liệu xanh, sở khoa học công nghệ tp-hcm trung tâm thông tin khoa học công nghệ 2012, PP.7-88 103 Study on the Operating Characteristics of Cell Electrodes in a Solid Oxide Fuel Cell (SOFC) Through the TwoDimensional Numerical Simulation Method 1,2(&) XuanVien Nguyen , PhamTrungKhanh Luong , ThiNhung Tran , MinhHung 1 Doan , AnQuoc Hoang , and ThanhTrung Dang Department of Thermal Engineering, HCMC University of Technology and Education, 01 Vo van Ngan Street, Thu Duc District, Ho Chi Minh City, Vietnam viennx@hcmute.edu.vn Renewable Energy Research Center, HCMC University of Technology and Education, 01 Vo van Ngan Street, Thu Duc District, Ho Chi Minh City, Vietnam Department of Chemical Technology, HCMC University of Technology and Education, 01 Vo van Ngan Street, Thu Duc District, Ho Chi Minh City, Vietnam Abstract This study presents a two-dimensional model for planar anode supported cells in a solid oxide fuel cells (SOFCs) The model is implemented with planar cm cm anode supported cells (with an active area of cm cm) The performance characteristics within each cell of the SOFC (cathode, anode, and electrolyte layer) are determined via the numerical simulation method This method is based on the fundamental conservation laws of conti-nuity, momentum, energy, and mass The effects of the cathode, anode, and electrolyte layer thickness are investigated at different temperatures The results show the behavior of the potential, temperature field, and current distributions in the cell when certain parameters (anode thickness, cathode thickness, electrolyte thickness, and temperature in the channels) are varied The effects of varying the fuel inlet and air inlet conditions are also presented and discussed Keywords: Solid oxide fuel cell Porosity Curvature Electrode Introduction Solid oxide fuel cells (SOFC) are the energy sources of future industries and have been widely applied in automotive, transportation, and portable electronics because of their light weight and efficiency They are a promising alternative technology to traditional power sources The main advantages of power production using SOFCs are the cells’ high conversion efficiency, the absence of combustion, and fuel flexibility, which allows use of various fuels, including those derived from renewable sources [1–4] © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2021 Y.-P Huang et al (Eds.): GTSD 2020, AISC 1284, pp 303–311, 2021 https://doi.org/10.1007/978-3-030-62324-1_26 304 X Nguyen et al Thus, research into the applications of solid oxide fuel cells (SOFCs) have become important and received much attention Kakac and Zhou [5] and Bove et al [6] performed comprehensive evaluations of the SOFC mathematical model Ni et al [7] proposed an electrochemical model to study fuel cell performance based on the proton-conduction of reversible solid oxide fuel cell (RSOFC) from electrolytes The authors concluded that the model can be successfully applied via a hydrogenelectrode-support on the SOFC and a solid oxide steam electrolyzer Jin and Xue [8] developed a temporary two-dimensional mathematical model (2-D) for URSOFC This model was tested with the results of NiO-YSZ, YSZ, and LSM cells prepared under different operational temperatures Many simulation studies have also been performed on SOFCs [9–13] Moreover, Zeng et al [14] studied solid oxide fuel cells (SOFCs) using optimized models, and the results indicated that the current density and thermal stress are related The proximity of these elements in the model is related to both the shape of the connector and the depth of the cathode Nerat et al [15] provided the amplitude and position of the maximum temperature (Tmax) and maximum temperature slope (DT/Dxmax), as well as the model performance parameters This model supports the anodes of solid oxide fuel (SOFC) and was developed using the COMSOL Multiphysics software Iora et al [16] studied a one-dimensional model for an SOFC–SOEC stack The results were compared with those obtained for an earlier simplified lumped volume model This paper studies the operating characteristics of cell electrodes in a solid oxide fuel cell (SOFC) using a two-dimensional numerical simulation method Due to the cell’s advantageously high temperature properties, hydrogen in the cell spreads through a porous hydrogen electrode and combines with the oxygen ions from the oxygen electrode to produce steam and then flows through the outer circuit to generate elec-tricity On the other hand, the majority of this work’s simulations are devoted to developing a 2-D axisymmetric mathematical model of URSOFC characteristics, including the species distributions, the cell performance, and the temperature distri-butions The effects of different operating conditions with input temperatures of 600, 700, and 800°C on cell performance are also considered in this paper Mathematical Model A 2-dimensional symmetry model was adopted in the current investigation This model includes adjustment equations to simulate the exchange behaviors, charge, and tem-perature of the species, as well as the constitutive correlation to calculate the flow density In addition, a medium porous model is used to simulate the effective properties of porous electrodes that can be considered a rectangular flat sheet The effects of convection in the electrode are not, however, considered in the present model The species transport characteristics are then assumed to be caused by the dispersion in the electrode as a result of the slope of the concentration using the following diffusion equation [17–19]: Study on the Operating Characteristics of Cell Electrodes A where V eff area per unit volume eff where D persion(D eff K;/ formula where Deff;/ depends on the porosity (e) and tortuosity (s) of the electrodes m Deff K;/ eff where D K;/ is the effective diffusivity in the porous electrode and consists of the Knudsen diffusion dp ¼ Results and Discussion −1 In the SOFC mode, oxygen at a standard flow rate of 400 ml.min and H2 at a flow −1 rate of 200 ml.m were supplied to the electrode surface As shown in Fig 1, the measurement performance curve of the parameters was determined by simulation and showed good agreement between the measurement results and prediction results [7, 17, 20–22] In addition, the exchange current density of the electrode is considered to be a free parameter and is used to fit the measurement data to a cell voltage of 0.575 V This is done because of changes in the adjustable parameter values leading to prediction differences 306 X Nguyen et al Fig Voltage and current density in SOFC modes at T = 650 °C Fig Predicted distribution concentration of H mol in the hydrogen electrode for the SOFC, T = 650 °C, V = 0.19 V The cell performance decreases as the porosity increases This predicted result is similar to that obtained by Li et al [23] In their work, the cell overpotential increased by increasing the porosity resulting from reduced reaction active sites Figure shows the process of cell exchange in the hydrogen electrode The oxygen generated from the Study on the Operating Characteristics of Cell Electrodes oxygen electrode passes through the YSZ electrolyte, arrives in the YSZ/Ni hydrogen electrode, and combines with hydrogen to produce steam and electrons In this region, the high concentration (red) gradually changes to a lower one (blue) Consequently, only a small amount of hydrogen can react beyond this interval The predicted distribution of the hydrogen concentration in the hydrogen electrode and SOFC was determined under a temperature of 650 °C and a cell voltage of 0.19 V The model is thus initially established for greater clarity, and most of the hydrogen is depleted at the interface of the electrolyte and the hydrogen electrode Since the size of the hydrogen electrode is larger than that of the oxygen electrode, most of the hydrogen is consumed in the central part of the hydrogen electrode The effect of electrolyte thickness on the cell exchange operations is small, as shown in Fig Fig Comparison of voltage and current density in the SOFC mode under different electrolyte thicknesses Figure shows the performance voltage and current density of the SOFC operating at the different operating temperatures of 650 °C, 750 °C, 800 °C, and 850 °C The corresponding comparison of the SOFC voltage and current density shows that the results of the forecast are in good agreement with the measured data As the temper-ature increases, the cell performance also increases as the temperature in the SOFC increases This occurs due to the increase of the ionic conductivity in the electrolyte and the increase of the electrochemical reaction in the electrode at higher temperatures The model predictions show the beneficial effect of temperature on cell performance 308 X Nguyen et al Fig Comparison of the voltage and current density in the SOFC mode under different temperatures A simulation was used to observe the activities while operating in the SOFC mode at 650 °C The SOFC cell productivity increased by increasing the edge of the H electrode, as clearly shown in Fig The predicted result shows that the effect of decreasing the flow resistance for a wider edge on cell performance outweighs the effect of decreasing electrochemical resistance Moreover, in the oxygen electrode, the cell performance is less significant for the O2 electrode than for the H2 electrode (as shown in Fig 6) because the SOFC is a hydrogen electrode support cell, and the thickness of the H2 electrode is 540 lm, which is significantly thicker than the 25 lm of the O2 electrode Based on the results of similar articles, for SOFC performance changes based on shape and size, a smaller edge is known to enhance the surface reaction within the electrode and consequently reduce electrochemical resistance [24] However, a smaller edge in the electrodes can also increase flow resistance due to the larger contact area between the gas and particles when the fuel passes through the porous electrodes [25] Study on the Operating Characteristics of Cell Electrodes Fig Comparison of OCV in the SOFC mode under different hydrogen electrode thicknesses Fig Comparison of OCV in the SOFC mode under different oxygen electrode thicknesses 310 X Nguyen et al Conclusions A thorough 2D numerical simulation of electrodes was developed in this paper to study the applications of SOFCs, which are considered a promising next-generation energy source and storage device The SOFC was numerically investigated in this study to predict its parametric effects and cell performance The species concentration and temperature distributions also affect the performance of this model The predicted results show that the chemical reaction and mass transfer rates increase by increasing the temperature, which is clearly indicated by the chart voltage and current density in the SOFC In addition, the cell performance increases by increasing the electrode porosity, and the improvement in mass transfer exceeds the effect of the decrease in reaction sites for larger porosity values Several important conclusions were thus determined based on the simulation results of the SOFC Moreover, cell performance increases by increasing the diameters of the H electrode and the O2 electrode This simulation ultimately predicted that the effect of reducing the flow resistance for a larger size is reliant on the performance and applicability of the proposed 2-D axisymmetric model Acknowledgments This research was funded by the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 107.03−2018.332 Conflicts of Interest The author declares no conflict of interest References Singhal, S.C.: Advances in solid oxide fuel cell technology Solid State Ionics 135(1–4), 305–313 (2000) Laguna-Bercero, M.A.: Recent advances in high temperature electrolysis using solid oxide fuel cells: A review J Power Sources 203, 4–16 (2012) Choudhury, A., Chandra, H., Arora, A.: Application of solid oxide fuel cell technology for power generation-a review Renew Sustain Energy Rev 20, 430–442 (2013) Nguyen, X.V.: Fabrication and performance evaluation of six-cell two-dimensional configuration solid oxide fuel cell stack based on planar 6 cm anode-supported cells Energies 12(18), 3541–3549 (2019) Kakac, S., Pramuanjaroenkij, A., Zhou, X.Y.: A review of numerical modeling of solid oxide fuel cells Int J Hydrogen Energy 32(7), 761–786 (2006) Bove, R., Ubertini, S.: Modeling solid oxide fuel cell operation: approaches, techniques and results J Power Sources 159(1), 543–559 (2006) Ni, M., Leung, M.K.H., Leung, D.Y.C.: Theoretical analysis of reversible solid oxide fuel cell based on protonconducting electrolyte J Power Sources 177(2), 369–375 (2008) Jin, X., Xue, X.: Mathematical modeling analysis of regenerative solid oxide fuel cells in switching mode conditions J Power Sources 195(19), 6652–6658 (2010) Celik, A.N.: Three-dimensional multiphysics model of a planar solid oxide fuel cell using computational fluid dynamics approach Int J Hydrogen Energy 43(42), 19730–19748 (2018) Study on the Operating Characteristics of Cell Electrodes 10 Qu, Z., Aravind, P.V., Boksteen, S.Z., Dekker, N.J.J., Janssen, A.H.H., Woudstra, N., Verkooijen, A.H.M.: Three-dimensional computational fluid dynamics modeling of anodesupported planar SOFC Int J Hydrogen Energy 36(16), 10209–10220 (2011) 11 Li, A., Song, C., Lin, Z., et al.: A multiphysics fully coupled modeling tool for the design and operation analysis of planar solid oxide fuel cell stacks Appl Energy 190, 1234–1244 (2017) 12 Ay, S., Ferng, Y.-M., Wang, C.B.: Investigating parametric effects on performance of a high-temperature URSOFC Int J Energy Res 39(5), 648–660 (2015) 13 Kong, W., Li, J., Liu, S., Lin, Z.: The influence of interconnect ribs on the performance of planar solid oxide fuel cell and formulae for optimal rib sizes J Power Sources 204, 106 – 115 (2012) 14 Zeng, S., Zhang, X., Chen, J.S., Li, T., Andersson, M., et al.: Modeling of solid oxide fuel cells with optimized interconnect designs Int J Heat Mass Transf 125, 506–514 (2018) 15 Nerat, M., Juricic, Ð.: A comprehensive 3-D modeling of a single planar solid oxide fuel cell Int J Hydrogen Energy 41(5), 3613–3627 (2016) 16 Iora, P., Taher, M.A.A., Chiesa, P., Brandon, N.P.: A one dimensional solid oxide electrolyzer-fuel cell stack model and its application to the analysis of a high ef ficiency system for oxygen production Chem Eng Sci 80, 293–305 (2012) 17 Jin, X.F., Xue, X.J.: Mathematical modeling analysis of regenerative solid oxide fuel cells in switching mode conditions J Power Sources 195, 6652–6658 (2010) 18 Suwanwarangkul, R., Croiset, E., Fowler, M.W., Douglas, P.L., Entchev, E., Douglas, M.A.: Performance comparison of Fick’s, Dusty-gas and Stefan-Maxwell models to predict the concentration overpotential of a SOFC anode J Power Sources 122, 9–18 (2003) 19 Andreassi, L., Rubeo, G., Ubertini, S., Piero, L., Roberto, B.: Experimental and numerical analysis of a radial flowsolid oxide fuel cell Int J Hydrogen Energy 32(17), 4559–4574 (2007) 20 Grondin, D., Deseure, J., Brisse, A., Zahid, M., Ozil, P.: Simulation of a high temperature electrolyzer J Appl Electrochem 40, 933–941 (2010) 21 Shi, Y., Cai, N.S., Li, C.: Numerical modeling of an anodesupported SOFC button cell considering anodic surface diffusion J Power Sources 164, 639–648 (2007) 22 Ay, S., Ferng, Y.M., Wang, C.B., Cheng, C.H.: Analytically investigating the characteristics of a high temperature unitized regenerative solid oxide fuel cell Int J Energy Res 37(13), 1699–1780 (2013) 23 Li, W.Y., Shi, Y.X., Luo, Y., Cai, N.S.: Theoretical modeling of air electrode operating in SOFC mode and SOEC mode: the effects of microstructure and thickness Int J Hydrogen Energy 39(25), 13738–13750 (2014) 24 Bae, J.W., Hong, S.W., Koo, B.G., An, J.H., Prinz, F.B., Kim, Y.B.: Influence of the grain size of samariadoped ceria cathodic interlayer for enhanced surface oxygen kinetics of low-temperature solid oxide fuel cell J Eur Ceram Soc 34(15), 3763–3768 (2014) 25 Pham, A.T., Baba, T., Shudo, T.: Efficient hydrogen production from aqueous methanol in a PEM electrolyzer with porous metal flow field Influence of change in grain diameter and material of porous metal flow field Int J Hydrogen Energy 38(24), 9945–9953 (2013) THE 5TH INTERNATIONAL CONFERENCE ON GREEN TECHNOLOGY AND SUSTAINABLE DEVELOPMENT (GTSD2020) CERTIFICATE OF PARTICIPATION This is to certify that LUONG PHAM TRUNG KHANH has joined and been a presenter in the online session PS3: Green Energy and Power Systems of the virtual conference GTSD2020 which was held on 27-28 November, 2020 in Ho Chi Minh City, Vietnam Professor Do Van Dung President of Ho Chi Minh City University of Technology and Education Honorary Chair of GTSD2020 ... oxit rắn thực qua đề tài ? ?Nghiên Cứu Các Đặc Tính Hoạt Động Của Các Điện Cực Trong Pin Nhiên Liệu Oxit Rắn (SOFC) Bằng Phương Pháp Mô Phỏng Số? ?? 18 1.2 Các nghiên cứu liên quan 1.2.1 Tình hình nghiên. .. PHỐ HỒ CHÍ MINH LUẬN VĂN THẠC SĨ LƯƠNG PHẠM TRUNG KHÁNH NGHIÊN CỨU CÁC ĐẶC TÍNH HOẠT ĐỘNG CỦA CÁC ĐIỆN CỰC TRONG PIN NHIÊN LIỆU OXIT RẮN (SOFC) BẰNG PHƯƠNG PHÁP MÔ PHỎNG SỐ NGÀNH : KỸ THUẬT NHIỆT... PHỐ HỒ CHÍ MINH LUẬN VĂN THẠC SĨ LƯƠNG PHẠM TRUNG KHÁNH NGHIÊN CỨU CÁC ĐẶC TÍNH HOẠT ĐỘNG CỦA CÁC ĐIỆN CỰC TRONG PIN NHIÊN LIỆU OXIT RẮN (SOFC) BẰNG PHƯƠNG PHÁP MÔ PHỎNG SỐ NGÀNH : KỸ THUẬT NHIỆT