考虑边界约束条件的C/SiC壁板热屈曲试验研究  

Thermal Buckling Tests of C/SiC Plates with the Special Restricted Boundary Conditions

作　　者：吴振强[1] 宫文然[1] 程昊[1] 贾洲侠[1] 方国东[2] WU Zhen-qiang;GONG Wen-ran;CHENG Hao;JIA Zhou-xia;FANG Guo-dong(Science and Technology on Reliability and Environmental Engineering Laboratory,Beijing Institute of Structure and Environment Engineering,Beijing 100076,China;National Key Laboratory of Science and Technology on Advanced Composites in Special Environments,Harbin Institute of Technology,Harbin 150080,China)

机构地区：[1]北京强度环境研究所可靠性与环境工程技术重点实验室,北京100076 [2]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

出　　处：《强度与环境》2021年第6期17-23,共7页Structure & Environment Engineering

基　　金：国家自然科学基金联合基金项目(U20B2002);重点实验室基金项目(6142905193210)。

摘　　要：当热变形受到限制或承受非均匀温度场时,复合材料壁板易发生热屈曲现象,导致出现分层或改变了结构的动力学特性,严重影响着飞行器结构的完整性。本文选取典型C/SiC壁板为试验件,设计了水冷边界工装,采用双向限制位移方法模拟试验件的边界约束状态。基于石英灯加热装置,开展了不同升温速率下的热屈曲试验,采用热像仪和数字图像相关技术等测试获取了真实的温度场和变形场。同时开展了不同温度状态下的热模态试验。依据壁板中心点离面位移变化和第1阶固有频率变化计算得到热屈曲临界温度,并作对比分析,可为热防护结构设计和力热试验验证提供技术支撑。Thermal buckling of composite plate occurs easily when the thermal deformation is restricted or thermal load is not uniform.Delimitation of composite plate is also induced by the thermal buckling and the structural dynamic characteristic is also changed.It presents a significant challenge for the integrity of thermal protection structures.Here,a typical C/SiC plate is chosen,and a mounting frame is cooled by the water.The displacements along in-plane and out-of-plane directions are all restricted by this mounting frame.The testing plate is heated by a quartz lamp apparatus,and thermal buckling tests with the different heating rate are carried out.Accurate temperature field is measured by the thermal imaging system.The deformation field is gained by a digital image correlation(DIC)system.Moreover,thermal modal tests are executed within different thermal environments.The critical buckling temperatures based on out-of-plane displacement and the first natural frequency are calculated and compared.These results are very vital to structure design and thermal-mechanical tests.

关 键 词：C/SiC壁板 热变形 热屈曲临界温度 离面位移 固有振动频率 

分 类 号：V416.4[航空宇航科学与技术—航空宇航推进理论与工程]