采用双三次样条方法建立了某型固体火箭发动机特型喷管扩张段型面;考虑燃气流动和温度的耦合影响,采用二维轴对称可压缩N-S方程进行数值仿真分析。以发动机推力和总压恢复系数最大为优化目标,模拟退火算法寻优进行了特型喷管的优化设计,与初始设计方案相比,轴向推力提高2.38%,总压恢复系数提高2.22%。结果表明:特型喷管性能远优于锥形喷管,通过对型面的优化设计可以提高喷管性能。

A new profile design method for SRM nozzle was proposed, and the profile optimization was completed to improve the nozzle performance. Bi-cubic spline was used to construct the nozzle divergent section profile. Two-dimensional compressible axisymmetric N-S equations were used to do the numerical simulation with considering the coupling effects of gas flow and heat transfer. Finally, the adaptive simulated annealing algorithm was used to complete the profile optimization, with the objectives of the maximum thrust and minimum total pressure loss. The optimization increases the axial thrust of engine by 2.38%, and enhances the total pressure recovery coefficient by 2. 22%. The result shows that the shortened nozzle has much better performance than conical nozzle when they are the same long as divergent section. The result also shows that the nozzle performance can be improved through the optimization of section profile.