航天器防护瓦脱落力学分析

The Mechanics Analysis of Desquamation for Thermal Protection System(TPS) Tiles of Spacecraft

以固体力学为基础研究了航天器中热防护瓦的脱落问题。通过考查防护瓦与机体间粘接面上剥离应力的存在,建立了新的力学模型,满足了粘结面上剪切应力的边界条件,克服了传统剪滞理论的缺点,并对航天器防护瓦的脱落做出了合理解释。进一步并分析了防护瓦长度、厚度及材料对剥离应力的影响,进而为防护瓦的设计提供力学参考建议。

On the basis of solid mechanics, the ＂Peeling off ＂ problem of TPS tiles on space craft surface is investigated. After considering the existence of peeling stress along the interface between the TPS tiles and the frame of space shuttle, a new model of mechanics is established to satisfy the boundary conditions of shear stress, which cannot be satisfied by the traditional shear-lag model. According to these new solutions, the reasonable explanation can be made about the failure of glued joint for TPS tiles. The stress distributions are studied when TPS tiles working in high temperature condition have different length, thickness, and material, and some advices can be provided to the design of TPS tiles.