Thermal and combustion optimization of agglomeration characteristics in aluminized composite propellants

The addition of aluminum particles in aluminized composite propellants can effectively enhance the energy characteristics of the propellants; however, it also brings about negative impacts such as specific impulse loss in two-phase flow and intensified ablation. Reducing the particle size of the condensed products of aluminized composite propellants can effectively improve the performance of the solid rocket motor. Nevertheless, a reduction in the particle size of the condensed products will result in a decrease in the thermal and combustion characteristics of the propellants and a decline in the overall performance of the propellants. A calculation method of energy characteristics that can reflect the oxidation degree and combustion efficiency of Al particles is proposed. Kriging approximation model theory is used to establish an approximate model of propellant agglomeration characteristics and energy characteristics, and the sensitivity of propellant agglomeration characteristics and energy characteristics to each design parameter is explored. Multi-objective optimization of the approximate model is carried out with the multi-objective bat algorithm. On the basis of ensuring the thermal and combustion characteristics of propellants, the solution set of the optimal formula with the minimum particle size of the initial condensed product is obtained, which provides guidance for the formulation design of propellants.