热防护中的粒状剥蚀问题研究  

The grainy denudation in heat shield

作　　者：李干[1] 汤文辉[1] 冉宪文[1] 龚德良[2] 

机构地区：[1]国防科学技术大学理学院,长沙410073 [2]湘南学院计算机科学系,郴州423000

出　　处：《航天器环境工程》2010年第6期747-750,674,共4页Spacecraft Environment Engineering

摘　　要：粒状剥蚀是机械剥蚀的主要形式之一,对纤维复合材料的热防护性能有重要影响。通过理论分析得到了烧蚀达到稳定状态时纤维形状的表达式,在此基础上建立了粒状剥蚀问题的力学分析模型。通过受力分析,采用莫尔破坏准则建立了判断纤维复合材料是否发生粒状剥蚀的条件。根据判别条件,材料纤维和基体的性能差异、外流场速度以及纤维尺寸都将显著地影响纤维复合材料的剥蚀性能。The grainy denudation is one of the most important modes of mechanical denudations,which has a great influence on the heat shield of fibrous composites.The formulas for fibre's shape are obtained by a steady-state analysis.Based on the formulas,a mechanical model is set up to solve the grainy denudation problem of fibrous composites.Using the Mohr criterion,an estimate can be made for deciding if grainy denudation occurs.According to the estimate,the differences between fibre and bulk,the outer fluid velocity and the fibre's dimension would markedly affect the denudation properties of fibrous composites.

关 键 词：热防护 粒状剥蚀 机械剥蚀 纤维复合材料 

分 类 号：V435+.14[航空宇航科学与技术—航空宇航推进理论与工程]