Multi-objective optimization of an ammonia-fueled micro planar combustor with a secondary oxygen injection for thermophotovoltaic applications

In order to address the issue about the multi-objective optimization of an ammonia-fueled micro planar combustor with a secondary oxygen injection for thermophotovoltaic applications, in this work, response surface methodology (RSM), non-dominated sorting genetic algorithm II (NSGA-II), entropy weight method (EWM) and technique for order preference by similarity to an ideal solution (TOPSIS) are combined. Firstly, the volumetric flow rate (VNH3), secondary oxygen injection ratio (Φ) and secondary oxygen injection position (L6) are selected as the design variables, and the total energy output of MTPV system (Qtot), total energy output efficiency of MTPV system (ηMTPV) and NO mole fraction at the outlet (γNO) are chosen as objection functions. Subsequently, the Box-Behnken design is utilized to arrange numerical investigations. With the obtained results, RSM and NSGA-II is combined to obtain Pareto frontier solutions. Finally, TOPSIS with EWM is used to select the optimal solution from the Pareto frontier solutions. The optimal Qtot, ηMTPV and γNO is 8.83 W, 7.17 % and 0.0139, respectively, and the corresponding design variable VNH3, Φ and L6 are 582.43 mL/min, 15.14 % and 11.68 mm, respectively.