摘要
热防护材料在高温、高焓、高压环境中因物理、化学和力学因素造成质量损失引起材料烧蚀,使其热力学和热物理性质发生不可逆变化,表现出复杂的非线性特征。通过对碳基复合材料热化学烧蚀机理分析,由质量守恒、能量守恒及系统化学反应的热化学平衡原理,建立相应的热化学和热力学烧蚀模型。基于材料线烧蚀引起边界移动建立热传导方程;对温度场以及热应力场求解时充分考虑材料变物性特征。通过数值模拟表征材料在高温烧蚀条件下的动态热力学行为,与实验结果吻合较好,实现了材料在高温、高过载等复杂因素耦合作用下的实时仿真。
The mass loss of thermal protection material under the condition of high temperatures, enthalpies and pressures is caused by physical, chemical and mechanical factors and the change of material thermomechanical properties and thermophysical properties at high temperatures is irreversible, showing complex nonlinear characteristics. The present paper is devoted to the development and establishment of corresponding thermochemical and thermomechanical ablative models by analyzing flow and C/C composite materials ablative mechanism. With the help of the conservation law of mass and energy and thermochemical equilibrium of system chemical reaction, the thermal conduct equation is presented based on a moving boundary caused by linear ablation; the mathematical equation is solved numerically by a nonlinear coupling scheme, while the changes of material properties with temperature are considered. The calculated results characterize the dynamic thermomechanical behavior of the material in special environments such as high temperature. This analysis accords well with experimental data. The analysis realizes instantaneous simulation of ablation effected by complex coupling factors of high temperature and load.
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2006年第5期143-148,共6页
Acta Materiae Compositae Sinica
基金
国家自然科学基金资助项目(10572044
90405016)
关键词
C/C复合材料
热化学性质
热力学性质
烧蚀
carbon- carbon composites
thermochemical analysis
thermomechanical analysis
ablation
