硅基材料烧蚀模型研究

对冲压发动机燃烧室所使用的硅基热防护材料，用以往的单纯因二氧化硅液态层被气动吹除减薄的模型进行烧蚀计算，计算结果和实际偏差很大。我们根据硅基热防护材料的实际特性，在原有的液态层模型的基础上，考虑了夹杂碳化层对熔融态硅基的补强作用，提出了既有液态层吹除也有化学反应烧蚀的新模型，即考虑了热解、熔融和碳化、气动吹除结合化学反应烧蚀的多因素过程。并根据硅基热防护材料的烧蚀特点，根据发动机模型的试验结果，初步总结出了液态层粘附力的经验公式。从物理概念上分析可以看出该模型基本符合实际情况；从多种工况计算结果可看出，新模型和经验公式是比较合理的。

Study on ablation model of silica-reinforced composites

Previous models of ablation computation about Silica-reinforced thermal protection materials used in the combustion of ramjet engines only simulated the recession of silica liquid layer due to aerodynamics blow,thus,the results did not match the reality well.Based on the former liquid layer model,a new model was proposed considering the strengthen function of mixed carbon layer to molten silicon,which concluded the blow of liquid layer and ablation with chemical reaction,i.e.the multi-factor process of pyrogenation,liquation and carbonization,as well as blow and ablation with chemical reaction,were simulated in the model.And then preliminary experiential formula for liquid layer adhesion were brought out,according to the ablativity of Silica-reinforced thermal protection materials and experimental data of ramjet engines.Analyzed physical concept,the model is in good agreement with reality.And the multi-cases results indicate that the new model and experiential formula are rational.