基于统计均匀化技术的多层结构界面脱粘热力耦合研究

Under the effect of thermo-mechanical interaction, interfacial debonding phenomena probably occur in multilayer structures and cause catastrophic accident directly in serious situation. Therefore, it is necessary to carry out the research of thermo-mechanical interaction of multilayer structures with interfacial debonding. And so far, it is lack of the integrated thermo-mechanical model and the effective solving method. Micro-asperity contact model presented by Sista and Vemaganti is extended to the field of heat transfer and the integrated thermo-mechanical constitutive model is constructed. Based on statistical homogenization techniques, the constitutive relations of thermal contact resistance under high temperature are derived and connected the interfacial micro parameters with macro parameters. Experimental research of thermal contact resistance are completed in vacuum environment and under high pressure from 5 to 25 MPa and high temperature from 500℃ to 1500℃. The equivalent macroscopic model is constructed. Then effective numerical method and reliable platform for solving thermo-mechanical interaction with interfacial debonding are studied. Through the theoretical and experimental research of interfacial thermo-mechanical behavior, it promotes spacecraft engineering and has significance value to academic research and engineering application.

热力耦合作用下，多层结构出现界面脱粘现象，重者直接造成灾难性事故，因此有必要进行多层结构界面脱粘热力耦合研究。而目前为止尚缺乏统一的界面热力学模型和有效的求解方法。本项目拟将Sista和Vemaganti提出的微凸峰接触模型从摩擦学研究扩展到传热学研究，建立统一的界面热力学模型；基于统计均匀化技术，将界面微观量与宏观量联系起来，建立高温接触热阻的本构关系；开展真空、中高压（5—25MPa）载荷以及高温（500℃—1500℃）环境下接触热阻的实验研究；构造等效的宏观模型，建立多层结构界面脱粘热力耦合问题有效的数值计算方法和可靠的计算平台。通过界面热力学行为的理论和实验研究，推动它走向工程实际应用，既具有重要的学术意义也具有工程应用价值。

多层结构热力耦合计算中有必要考虑界面脱粘引起的界面热力学特性改变。本项目将Sista和Vemaganti提出的微凸峰接触模型从摩擦学研究扩展到传热学研究，基于统计均匀化技术建立了统一的界面热力学模型，获得宏观静摩擦系数和接触热阻与接触压力的参数化表征。开展了接触热阻试验件和测试装置的设计，搭建了接触热阻的测试平台，着重考察了表面粗糙度、温度和接触压力等因素对接触热阻的影响，并与理论计算进行对比。将宏观静摩擦系数和接触热阻与接触压力的参数化表征嵌入到热力耦合分析中，实现了多层结构界面脱粘的多尺度热力耦合计算。研究成果具有重要的学术价值，为多层结构界面脱粘的多尺度热力耦合计算提供了一种新途径。采用边界元法和共轭梯度法相结合的方法研究了接触热阻的反问题求解方法，基于最小二乘法处理不适定性问题，使得接触热阻反演结果更加逼近真实值。研究成果具有重要的工程应用价值，可作为工程接触热阻预测的一种快速有效的方法。