This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polyme...This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polymer electrolyte membrane) and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC (polymer electrolyte fuel cell). A 1D multi-plate heat transfer model based on the temperature data of separator measured using thermograph in a power generation experiment was developed to evaluate the reaction surface temperature (Treact). This study investigated the effects of flow rate, relative humidity and type of supply gas as well as Tini on the temperature distribution on reaction surface. The results obtained in 02 supply case show that, the temperature rise at the segments near the outlet of cell decreases with increasing Tini irrespective of relative humidity of supply gas (RH), while it is not seen in air supply case. Regarding the segments except near the outlet in 02 supply case, Treact - Tini increases with increasing Tini for 40% RH. The temperature distribution on reaction surface in 02 supply case is wider with increasing Tini as well as decreasing RH, though that in air supply case is relatively even.展开更多
This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polyme...This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polymer electrolyte membrane) and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC (polymer electrolyte fuel cell). A 1D multi-plate heat transfer model based on the temperature data of separator measured using thermograph in a power generation experiment was developed to evaluate the reaction surface temperature (Treact). This study investigated the effects of Tini, flow rate and relative humidity of supply gas as well as thickness of PEM on the temperature distribution on reaction surface. As a result, the impact of flow rate of supply gas on the temperature distribution is not significant irrespective of relative humidity conditions as well as PEM type. When operated at high temperature, the temperature distribution is relatively flat in the case of thicker PEM (Nafion 115), while Treact rises from the inlet to the outlet large and the temperature distribution is wide in the case of thin PEM (Nafion 211) irrespective of relative humidity condition. Since the water transfer through PEM in the case of Nafion 211 is better than Nafion 115 due to thin PEM, the power generation is promoted along the gas flow with the aid of humidification by water produced from electrochemical reaction.展开更多
Abstract: The purpose of this study is to analyze the temperature distribution on the interface between the polymer electrolyte membrane and catalyst layer at the cathode in single cell of polymer electrolyte fuel ce...Abstract: The purpose of this study is to analyze the temperature distribution on the interface between the polymer electrolyte membrane and catalyst layer at the cathode in single cell of polymer electrolyte fuel cell when operated in elevated temperature range than usual. In this study, the interface between the polymer electrolyte membrane and catalyst layer at the cathode is named as reaction surface. This study has considered the 1D multi-plate heat transfer model estimating the temperature distribution on the reaction surface and verified with the 3D numerical simulation model solving many governing equations on the coupling phenomena of the polymer electrolyte fuel cell. The 3D numerical simulation model coverers a half size of actual cell including three straight parts and two turn-back corners, which can display the essential phenomena of single cell. The results from both models/simulations agreed well. The effects of initial operation temperature, flow rate, and relative humidity of supply gas on temperature distribution on the reaction surface have been investigated. Though the effect of flow rate of supply gas on temperature distribution on reaction surface has been small, low relative humidity of supply gas has caused higher temperature on the reaction surface compared to high relative humidity of the supply gas. The temperature rise of reaction surface from initial operation temperature has increased with the increasing in initial operation temperature of cell.展开更多
For improving the performance of stationary PEFC (polymer electrolyte fuel cell) system, the cell operating temperature up to 90℃ will be preferred in Japan during the period from 2020 to 2030. To understand the op...For improving the performance of stationary PEFC (polymer electrolyte fuel cell) system, the cell operating temperature up to 90℃ will be preferred in Japan during the period from 2020 to 2030. To understand the operation of the PEFC system under relatively high temperature conditions, detail heat and mass transfer analysis is required. The purpose of this study is to analyze the impact of relative humidity of supply gas on temperature distribution on the backside of separator in single ceil of PEFC using Nation membrane at higher temperature e.g. 90℃. The in-plane temperature distribution when power was being generated was measured using thermograph with various relative humidity of supply gases. It was found that the in-plane temperature distribution at the anode was more even than that at the cathode irrespective of the relative humidity of supply gas at the anode and the cathode. The temperature elevated along gas flow through the gas channel at the cathode irrespective of relative humidity of supply gas at the anode and the cathode. The in-plane temperature distribution at the cathode was narrower with the increase in Tini irrespective of relative humidity of supply gas at the cathode, while it was not observed when changing the relative humidity of supply gas at the anode. When the relative humidity of supply gas at cathode decreased, the in-plane temperature distribution at the anode was wider compared to decreasing the relative humidity of supply gas at the anode. The study concluded that the impact of relative humidity of supply gas at both anode and cathode had little impact on the in-plane temperature distribution at the cathode.展开更多
文摘This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polymer electrolyte membrane) and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC (polymer electrolyte fuel cell). A 1D multi-plate heat transfer model based on the temperature data of separator measured using thermograph in a power generation experiment was developed to evaluate the reaction surface temperature (Treact). This study investigated the effects of flow rate, relative humidity and type of supply gas as well as Tini on the temperature distribution on reaction surface. The results obtained in 02 supply case show that, the temperature rise at the segments near the outlet of cell decreases with increasing Tini irrespective of relative humidity of supply gas (RH), while it is not seen in air supply case. Regarding the segments except near the outlet in 02 supply case, Treact - Tini increases with increasing Tini for 40% RH. The temperature distribution on reaction surface in 02 supply case is wider with increasing Tini as well as decreasing RH, though that in air supply case is relatively even.
文摘This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polymer electrolyte membrane) and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC (polymer electrolyte fuel cell). A 1D multi-plate heat transfer model based on the temperature data of separator measured using thermograph in a power generation experiment was developed to evaluate the reaction surface temperature (Treact). This study investigated the effects of Tini, flow rate and relative humidity of supply gas as well as thickness of PEM on the temperature distribution on reaction surface. As a result, the impact of flow rate of supply gas on the temperature distribution is not significant irrespective of relative humidity conditions as well as PEM type. When operated at high temperature, the temperature distribution is relatively flat in the case of thicker PEM (Nafion 115), while Treact rises from the inlet to the outlet large and the temperature distribution is wide in the case of thin PEM (Nafion 211) irrespective of relative humidity condition. Since the water transfer through PEM in the case of Nafion 211 is better than Nafion 115 due to thin PEM, the power generation is promoted along the gas flow with the aid of humidification by water produced from electrochemical reaction.
文摘Abstract: The purpose of this study is to analyze the temperature distribution on the interface between the polymer electrolyte membrane and catalyst layer at the cathode in single cell of polymer electrolyte fuel cell when operated in elevated temperature range than usual. In this study, the interface between the polymer electrolyte membrane and catalyst layer at the cathode is named as reaction surface. This study has considered the 1D multi-plate heat transfer model estimating the temperature distribution on the reaction surface and verified with the 3D numerical simulation model solving many governing equations on the coupling phenomena of the polymer electrolyte fuel cell. The 3D numerical simulation model coverers a half size of actual cell including three straight parts and two turn-back corners, which can display the essential phenomena of single cell. The results from both models/simulations agreed well. The effects of initial operation temperature, flow rate, and relative humidity of supply gas on temperature distribution on the reaction surface have been investigated. Though the effect of flow rate of supply gas on temperature distribution on reaction surface has been small, low relative humidity of supply gas has caused higher temperature on the reaction surface compared to high relative humidity of the supply gas. The temperature rise of reaction surface from initial operation temperature has increased with the increasing in initial operation temperature of cell.
文摘For improving the performance of stationary PEFC (polymer electrolyte fuel cell) system, the cell operating temperature up to 90℃ will be preferred in Japan during the period from 2020 to 2030. To understand the operation of the PEFC system under relatively high temperature conditions, detail heat and mass transfer analysis is required. The purpose of this study is to analyze the impact of relative humidity of supply gas on temperature distribution on the backside of separator in single ceil of PEFC using Nation membrane at higher temperature e.g. 90℃. The in-plane temperature distribution when power was being generated was measured using thermograph with various relative humidity of supply gases. It was found that the in-plane temperature distribution at the anode was more even than that at the cathode irrespective of the relative humidity of supply gas at the anode and the cathode. The temperature elevated along gas flow through the gas channel at the cathode irrespective of relative humidity of supply gas at the anode and the cathode. The in-plane temperature distribution at the cathode was narrower with the increase in Tini irrespective of relative humidity of supply gas at the cathode, while it was not observed when changing the relative humidity of supply gas at the anode. When the relative humidity of supply gas at cathode decreased, the in-plane temperature distribution at the anode was wider compared to decreasing the relative humidity of supply gas at the anode. The study concluded that the impact of relative humidity of supply gas at both anode and cathode had little impact on the in-plane temperature distribution at the cathode.