Optimization design for a cost-effective hybrid rocket motor

The parametric modeling of hybrid rocket motor (HRM) system is developed. The main factors affecting the cost of the main components such as thrust chamber are studied and the cost model is built. Using multi-island genetic algorithm (MIGA), multi-objective design optimization of HRM considering both the cost and performance is carried out, aiming to obtain an alternative design for solid rocket motor (named CPKM) of a lunch vehicle upper-stage. The results show that HRM can replace CPKM in the main function and part of the performance. Compared with CPKM, HRM possesses a 21.0% decrease in cost at the same speed increment, and possesses a 15.8% increase in the speed increment at the same cost. In the conceptual design stage of HRM, the expansion ratio has a strong linear relationship with the specific impulse, the length and the time. The main influential factors of the two optimization targets, the speed increment and cost, are the initial thrust and the fuel grain thickness.