| Fuel cell technology, which has broad research space and wide applications, is one of the main channels to be independent of fossil energy. The solid oxide fuel cell (SOFC) is one of applications on fuel cell technology, although SOFC are researched and developed later with hardest study conditions, it is highest in application efficiency with great research value.Nowadays, the research on SOFC focuses mainly on battery materials and is short of simulation study. Most fuel cell stacks system’s global simulation are located in Combined Heat and Power field, few are in the new technology which gets heat, power and gas together. Therefore, the study on simulation about SOFC in this paper has important academic values and also plays an important guiding role in practical use, which uses methane as fuel and bases on the new technology of getting heat and power and gas together. The simulation on the global system of SOFC which combines heat and power and gas together is discussed in this paper. The impact factors and change rules on the fuel cell system of SOFC are also considered with a purpose on exploring a new channel and mode applying in SOFC and opening an application idea about SOFC. So, the main work and achievements in this paper are summarized as follows:1, According to the obtained quantitative calculation of SOFC based on chemical thermodynamics and kinetics, at least four parameters are needed to get the fuel cell body simulation closed to the actual one:two parameters (a and jo) are used to describe the loss of the reaction kinetics, one parameter (ASRohm) to describe the ohmic losses, and another parameter (jL) to describe the loss caused by the concentration difference. The different behaviours of many aspects of SOFC can be studied by changing these parameters.2, In the process of two thermal electrical co-generation, the exhaust gas contains hydrogen, carbon monoxide, carbon dioxide, water vapor and methane. Combustion exhaust gas process and acting power generation are taken during the thermal electric co-generation process with the combustion chamber. The exhaust gas is seperated by heat exchanger repeatedly and the remaining methane re-enters the processing of the cathodic reaction change in the pure thermal electrical cogeneration processes.3, The body simulation shows that the output power and efficiency first increases with the fuel utilization increasing, then decreases. The maximum is got when the efficiency of the fuel is about92%. and both have the synchronous regularity. However, the battery voltage decreases as the fuel utilization increases, mainly due to the concentration polarization of the system and the increasing ohmic polarization.4, It can be got easily by comparing the two thermal electric co-generation processes that the thermal electrical co-generation of the pure thermal exchanger design is slightly better than the thermal electric co-generation process with the combustion chamber, mainly because of the different process modes of the methane in the exhaust gases, and another pan is the error and loss caused by the system design differences.5,The innovation of this paper is the process of getting hydrogen and carbon monoxide by seperating the exhaust gases, removing water vapor and carbon dioxide to re-use methane by the pure thermal electrical cogeneration model. Conclusions according to the simulation contains the efficiency in pure thermal cooperation maintained at about53%, and the efficiency of the cogeneration with CH4:air volume ratio increases large increase to about60%in the condition of ensuring that methane is not completely oxidated. Therefore the design of a SOFC systems for the purpose of gas separation is not only reasonable and feasible, but also efficient and useful. |
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