极端环境下复合材料复杂结构/防热一体化引起的多场耦合机理及其分析方法研究

In the new project for near-space vehicles, the surface structure layer consists of lots of composite components, which are connected by the plenty of bolts. This layer is subjected to severe aerothermodynamic environment，the radiation is the main thermal protection mechanism on the surface of this layer (namely the integration of structure and thermal protection ). For the purpose of protecting the internal payload from the destruction of extremely high temperature, it is necessary to install the effective thermal insulation layer in the back surface of the structure layer. The outside and back surfaces for the structure layer are the multi-fields aerothermodynamic- mechanics- heat- pyrolysis coupled interfaces. Currently, the important multi-fields coupled scientific problem caused by the integration of structure and thermal protection has not been figured out. Based on the great demand of the new near-space hypersonic vehicle, this project treat the SiC matrix complex composites structure & the thermal insulation layer under severe aerodynamic heat as the main research object. It take advantage of the cross of multi-disciplinary to carry out the researches on experiment, theory and numerical simulation in view of the aerothermodynamic-mechanical-heat-pyrolysis multi-fields coupled mechanism caused by the integration of structure and thermal protection. Through these researches, the change rule of the thermal stress of the structure layer under the aerodynamic force, the aerodynamic heat and the pyrolysis is explored. This work will break through the key technology for the matching design about the overall performance of the structure and heat insulation, complete the verify ground test and the performance characterization, and develop a new thermal structure optimization evaluation system. This study will not only provide the theoretical direction and technical reserves for the innovation application of near-space hypersonic aircraft, but also promote the cross of interdisciplinary which is of great importance for the theoretical research. All in all, this project has significant national defense application value.

在近空间高超音速飞行器的新设计方案中，由多个复合材料构件通过螺栓连接而成的结构层承受极端的气动力与气动热，并通过高温表面的热辐射来防热（即：结构/防热一体化），为了飞行器内部的有效载荷免受高温破坏，结构背面上加装热解隔热层；结构层的外表面与背面成为气动热-力-热-热解多场耦合的界面；结构/防热一体化引起的多场耦合科学问题尚未解决，亟待研究。本项目基于新型近空间高超音速飞行器的重大需求，以极端环境下SiC基复合材料复杂结构+隔热层为研究对象，利用多学科的交叉创新，针对复杂结构/防热一体化引起的气动热-力-热-热解多场耦合机理开展试验、理论与数值模拟研究，探索结构的热应力在气动力、气动热与热解隔热联合作用下的变化规律，突破极端环境下结构-隔热综合性能匹配设计的关键技术，完成试验验证及性能表征工作。本项目将为飞行器上的创新应用提供技术储备，并推动交叉学科的发展，具有重要的理论意义和国防应用价值。

基于新型近空间高超音速飞行器的重大战略性需求，需要碳化硅复合材料与树脂基复合材料相结合的防隔热方案，新的方案对飞行器热防护科学和技术提出了严峻的挑战。本项目实施以来，紧紧围绕“极端环境下复合材料复杂结构/防热一体化引起的多场耦合”的关键科学问题，以气动热条件下 SiC 基防热复合材料+树脂基隔热复合材料为主要研究对象，利用复合材料力学、气动热力学、高温试验力学、传热传质学等多学科的交叉创新，针对主要防隔热复合材料复杂结构引起的气动热-力-热-热解等多场耦合机理开展试验、理论与数值模拟等研究，探索了结构的热应力在气动力、气动热与热解隔热作用下的变化规律，突破了气动热条件下复合材料复杂结构-隔热综合性能匹配设计的关键技术，完成了地面试验验证，可以实现新型防隔热结构的优化评价，为近空间高超音速飞行器热防护的创新应用提供理论指导和技术储备。.在本项目资助下，研究组成员发表论文28篇，其中27篇SCI收录；发布的标准2个；申请发明专利7项，其中已授权的2项，在审的5项；在国际学术会议或国内学术会议上做了多次研究报告。毕业博士生4名、毕业硕士生3名，在读博士生5名，在读硕士生3名，为我国航天工程培养了一支多学科交叉合作、年富力强的高水平研究队伍。本项目研究将推进交叉学科的发展，具有重要的理论意义，又具有重要的航天工程应用价值。