高温合金与C/C复合材料间高温接触热阻模型及减阻机理

The heat-pipe-cooled leading edge is an efficient thermal protection method in hypersonic aircraft design, and the thermal contact resistance between the high-temperature heat pipes and C/C composite material structure plays a very important role in heat transfer efficiency. Experimental and numerical researches on high-temperature thermal contact resistance are just at the beginning and is still an open issue both at home and abroad. In the present proposal, a testing platform of high-temperature thermal contact resistance is established firstly, and then the thermal contact resistance between super alloy GH600 and C/C composite material is tested under different interface materials, interface contact stresses, interface roughnesses and temperatures. At the same time, combined with the experimental research, a multiscale finite element model of high-temperature thermal contact resistance is established based on the multipoint contact theory with the consideration of interface radiation heat transfer. A practicle high-temperature thermal contact resistance model and the mechanism of the thermal contact resistance reduction with interface material are given at last. The present proposal not only has very important academic value, but also can be an important reference for the design and safety evaluation of heat-pipe-cooled thermal protection structures of near space hypersonic aircraft.

疏导式热防护是适用于高超音速飞行器翼前缘的高效热防护方法，影响其传热防热效果的一个关键因素是内置的高温热管与防热结构材料(C/C复合材料)之间的界面高温接触热阻。目前国内外关于高温接触热阻试验技术和数值模拟方法的研究尚处于起步阶段，存在许多迫切需要解决的重要问题。本项目首先搭建一套可用于高温接触热阻试验研究的测试平台，进而针对我国高超音速飞行器疏导式热防护结构中可能采用的高温合金GH600与C/C复合材料之间的高温接触热阻及其减阻机理进行试验研究，重点考察间隙填料厚度、接触应力、界面粗糙度和界面温度等因素对高温接触热阻的影响。同时，与试验研究相配合，基于考虑界面间隙辐射影响的多点接触理论建立高温接触热阻的多尺度有限元模型，最终建立工程实用的高温接触热阻测试方法及计算模型，并揭示其减阻机理。本项目不仅具有重要的学术价值，也可以为高超声速飞行器疏导式热防护系统设计与安全评估提供技术支持。

内置高温热管的疏导式热防护结构是实现高超音速飞行的一种高效热防护方法，影响其传热防热性能的一个重要因素是高温热管与耐热复合材料之间的界面高温接触热阻。本项目搭建了高温接触热阻的测试平台，并针对我国高超音速飞行器疏导式热防护结构中可能采用的材料之间的高温接触热阻及其减阻机理进行试验研究，重点考察间隙填料厚度、接触应力、界面粗糙度和界面温度等因素对高温接触热阻的影响。进而针对由接触热阻引起的热力耦合问题建立了间断Galerkin有限元格式。同时也针对内置高导C/C材料及高温热管的疏导式热防护结构的防热效果进行了研究，并给出了高温热管等效热导率的估算方法。研究成果不仅具有重要的学术价值，也可以为高超声速飞行器疏导式热防护系统设计与安全评估提供技术支持。