高硅氧/酚醛复合材料烧蚀环境下的吸热机理  

Endothermic mechanism of silica/phenolic composite under ablative environment

作　　者：时圣波[1] 梁军[1] 刘志刚[2] 丁小恒[1] 方国东[1] 

机构地区：[1]哈尔滨工业大学特种环境复合材料技术国防科技重点实验室,哈尔滨150080 [2]哈尔滨工业大学化学系,哈尔滨150080

出　　处：《固体火箭技术》2013年第1期113-118,共6页Journal of Solid Rocket Technology

基　　金：国家自然科学基金项目(90916027;11102051);中国博士后科学基金项目(20110491069)

摘　　要：通过分析高硅氧/酚醛复合材料烧蚀过程中的吸热机制,结合表面烧蚀理论和边界层空气动力学关系,应用质量引射影响系数的半经验公式,建立了烧蚀环境下吸热机理的理论预报方法,并利用氧乙炔焰动态烧蚀实验对该理论预报方法进行了验证。根据烧蚀过程达到稳态时烧蚀材料表面的能量守恒原理,推导了各吸热机理与总吸热量的比重关系,在给定的烧蚀环境工况下,预报了各吸热机理占总吸热量的比重。结果表明,熔融高硅氧纤维的蒸发吸热对总吸热量的贡献最大,所占比重为44.9%,是主要的吸热机制;材料的热容吸热和烧蚀材料向外界环境的热辐射占总吸热量的比重分别为22.3%和20.1%;树脂热解吸热所占比重很小,仅为1.0%,但热解气体引射进入边界层产生热阻塞效应占总吸热量的比重较大,为11.7%。Based on endothermic mechanism of silica/phenolic composite during ablation process, a theoretical prediction ap- proach to analyzing the endothermic mechanism of materials under ablative environment was presented by combining surface ablation theory with boundary layer aerodynamics, and the semi-empirical formula of mass injection factor was used. The theoretical predic- tion approach was validated by means of oxyacetylene flame dynamic ablation experiment. According to the energy conservation principle of ablative material surface under steady-state of ablation condition, the proportion formula of each endothermic mechanism and the total heat absorption was derived. Under a given ablation environment condition, the proportion of each endothermic mecha- nism in the total heat absorption was predicted. The results show that the evaporation of melting silica fiber is the main endothermic mechanism ,which account for 44.9% of the total heat absorption. The heat absorption of heat capacity of ablator occupies 22.3%, and heat radiation is up to 20.1% of the total heat absorption. Thermal decomposition of the resin gives the small contribution to the total heat absorption,which is 1.0% ,while the thermal blockage effect of the pyrolysis gases injected into boundary layer account for a higher proportion of 11.7% to the total heat absorption.

关 键 词：高硅氧 酚醛复合材料 吸热机理 热解反应 热阻塞效应 氧乙炔焰动态烧蚀实验 

分 类 号：V258[一般工业技术—材料科学与工程]