长时间工作固体火箭发动机燃烧室热防护层烧蚀计算

摘要

为了研究长时间工作固体火箭发动机燃烧室的热防护性能,运用三方程烧蚀模型和运动边界显示差分格式,对长时间固体火箭发动机内绝热层烧蚀及温度场进行了耦合计算.计算得到了化学烧蚀率、扩散烧蚀率、燃烧室内壁温度等参数.计算结果表明,所研究的长时间工作发动机燃烧室烧蚀由扩散过程控制.此外,在求解烧蚀子程序时,提出了一种简便有效的赋初值方法.采用文中方法在得到合理计算结果的同时,使得烧蚀计算时间大大缩短.该项研究为长时间工作固体火箭发动机燃烧室热防护层设计提供了有效的分析手段.%In order to study thermal-protection function of long-time working solid rocket motors, insulation ablation and temperature field of long-time working solid rocket motors were coupling calculated by moving boundary explicit-difference method and three equations ablation model. Ablation velocity caused by chemical reaction or diffnsion process and temperature of inner wall were calculated. Numerical results show that the ablation is restricted by the diffusion process. In addition, when solving the ablation subroutine,a convenient and effective method for setting initial value was proposed. Using this new method, the reasonable results were obtained and the calculation time was greatly decreased. This research can offer an effective analytical method for long-time working solid rocket motors.