在烧蚀条件下固体火箭发动机复合喷管的温度预示

THE TEMPERATURE PREDICTION FOR COMPOSITE NOZZLE OF SOLID ROCKET MOTOR UNDER ABLATION

关键词:  火箭发动机喷管  烧蚀  温度分布  固体火箭发动机

Key words:  Solid rocket engine  Ablation  Temperature distribution

摘要:

本文探讨了由石墨和高硅氧-酚醛组成的固体火箭发动机复合喷管,在考虑热解炭化和烧蚀引起喷管内型面变化条件下的瞬态轴对称二维温度场.借用当量热容的概念和坐标变换的方法,应用单元体能量平衡原理,在内点用显式格式,边界结点用隐式格式进行数值求解,这样的计算比较简捷,所得温度场与实验结果作了比较,说明本文的预示方法是可以符合工程精度要求的.

Abstract:

This paper presents the numerical simulation for axisymmetric two-dimensional transient temperature distribution in composite nozzle of solid rocket motor which consists of graphite and silica-phenolics under the condition of moving boundaries caused by charring and ablating recession. Based on the method of coordinate system transformation and the concept of equivalent heat capacity, the unified partial differential equations are formed from the principle of energy balance for the element area in different material layers.In numerical simulation, the explicit scheme is used for the inner nodes of the mesh in the computational plane,and the implicit scheme is used for the boundary nodes.The calculating process is rather forthright.Numerical results of a sample are compared with the experimental data,which shows that this method can meet the precision requirement for engineering design.