关键词: 火箭发动机喷管;热屏蔽层;温度分布

Abstract: In this paper,we carry out the numerical calculation on temperature distribution in silica-phenolics lining of divergent nozzle section using radial transient heat-conduction equations in cylindrical coordinates. For the construction of nozzle, the throat lining is made of graphite; the inner lining of convergent and divergent sections and the back lining of throat section are all made of silica-phenolics, and the outside layer of nozzle is made of steel. In the calculation, the multi-layer construction of charing layer, pyrolytic layer and origin material layer formed in ablation of the silica-phenolics, the recession of ablative boundary and the changes of physical properties of material with temperature have been taken into account. Through coordinate transformation, the moving boundary changes into a solid one.Mainly, there are two methods for the heat conduction calculation, one is energy balancing method in unit volume and the other partial, differential equations.An advantage of the later lies in easy couple of calculation with the ablation, which is just the cause for us further to study this method.In the paper, the improvements lie in adopting radial transient heat-conduction equations and considering pyrolysis taking place in certain thickness.We also carry out careful tests and measurements.The calculation results are in good agreement with measurements.

Key words: Rocket engine nozzle;Temperature field;Thermal shield