AP/HTPB复合推进剂微尺度燃烧模型及数值分析

A Microscale Combustion Model and Numerical Analysis of AP/HTPB Composite Propellant

关键词:  复合推进剂  微尺度燃烧  火焰结构  燃速 

Key words:  Composite propellant  Microscale combustion  Flame structure  Burning rate

摘要:

为了研究AP/HTPB复合推进剂微尺度燃烧与流动特性,建立了二维三明治结构的稳态燃烧模型。该模型考虑了气相火焰热反馈与固相组分热传导之间的耦合,通过对气相求解完整的N-S方程组,获得了AP/HTPB的燃速与微尺度燃烧场各物理量的分布特性。结果表明,随着环境压力升高,燃烧火焰由预混结构逐渐发展为扩散结构；压力越高,火焰热释放及其对燃面的热反馈越强,燃面的温度与燃速越高,燃速的计算结果与实验结果吻合较好；AP/HTPB交界点附近气体组分发生强烈的扩散反应,侧向速度对燃烧与流动有显著影响。 

Abstract:

To study the microscale combustion and flow characteristics of AP/HTPB composite propellant, a 2-D sandwich structure steady combustion model was established. The coupling between the heat feedback from gas-phase flame and the heat conduction of solid-phase ingredients was considered in the model. The burning rate and distribution characteristics of the physical parameters in the microscale combustion field of AP/HTPB were obtained by solving full Navier-Stokes equations for gas phase. Numerical results indicate that, the overall flame gradually develops from a premixed structure to a diffusion one with the increase of the ambient pressure. The higher the pressure, the stronger the flame heat release and its feedback to the burning surface, and the higher the temperature on the surface and burning rate. The calculated burning rate agrees well with the experimental results. Moreover, there occurs strong diffusion among gas species near the AP/HTPB interface, and the lateral velocity has a significant effect on the combustion and flow.