Multiobjective Optimization of Double-Wall Cooling Structure of Integrated Strut Flame Stabilizer and Sensitivity Analysis of Parameters

Abstract

The thermal environment behind the integrated strut of the afterburner is very harsh. A double-wall structure is set at the integrated strut flame stabilizer for cooling. The multiobjective optimization of the double-wall cooling structure is carried out by using the RBFNN-coupled nondominated sorting genetic algorithm II (NSGA-II), and the complex interaction between the film outflow and the mainstream was explored based on the numerical simulation results. The effects of geometric parameters and external working conditions on the cooling performance of the double wall are studied based on the Sobol method. The results show that the upward spiral vortex behind the strut will press the film outflow to form an irregular air film on the wall, effectively protecting the trailing edge of the strut. The optimized double-wall structure has a better air film coverage effect, and the comprehensive cooling performance has been improved to a certain extent. Compared with the geometric parameters, the mass-flow rate of the cooling gas per unit area has a greater impact on the comprehensive cooling performance of the double wall. The temperature ratio of the main and secondary flows has little effect on the comprehensive cooling performance of the double wall.