Simulation Study on Thermal Impact Effect and Performance of Tubular Ammonia SOFCs
Studying the thermal impact in ammonia solid oxide fuel cells(SOFCs)will provide opportunities for cells temperature management,reliability management and performance optimization.However,there has been little research conducted to investigate the thermal impacts generated due to the complicated physical fields and complex chemical and electrochemical reactions in ammonia SOFCs.For this reason,this study analyzes the thermal impacts in single direct ammonia cracking SOFCs by establishing a simulation model and coupling the endothermic ammonia cracking reaction,electrochemical reaction,local current distribution,temperature distribution and mass flow.As a result,the fast and unbalanced ammonia cracking reaction rate is the principal reason for the generating of the thermal impacts in SOFCs,and it directly causes a temperature difference of 376 K in the whole cell.Introducing the ammonia pre-reforming reaction can improve the temperature distribution.At the same operating voltage,ammonia SOFCs which introduce the ammonia pre-reforming reaction show a more uniform temperature distribution and higher average temperature.When the ambient temperature is 800℃,96%ammonia pre-reforming SOFCs will improve the temperature extreme difference in cell anode from 62.16K to 1.0K.This study can provide theoretical basis for the optimization of ammonia SOFCs thermal management,and the modeling method presented in detail in this paper can provide ideas for the simulation research of SOFCs fueled by other hydrogen-rich fuels.
solid oxide fuel cellcoupling modelthermal impacttemperature and species distributionammonia cracking reactionammonia pre-reforming