高孔隙材料的高温多光谱辐射特性与多尺度耦合传输机理

High-porosity materials have wide application and development prospects in the high-temperature solar energy conversion systems, high-temperature heat transfer enhancement, high-temperature thermal protection and so on. Aiming at the common high-temperature radiation and energy transport process in high-porosity materials, this project carries out theoretical and experimental research on the key scientific issues of multi-spectral radiation characteristics and multi-scale coupling transmission mechanism. . The main research contents include: the multi-scale coupled transfer mechanism and characteristics of the spectral radiation within the pore structure of foam materials, the experimental measurement method and technology of high-temperature multi-spectral radiative properties of porous materials, and the multi-scale analysis on high-temperature transient coupled heat transfer mechanism and characteristics in high-porosity materials. . By this research, the analytical methods for spectral radiation transfer in foam porosity level will be established to reveal the multi-scale coupled transfer mechanism, and the experimental method and technology of high-temperature spectral radiation properties is wished to be obtained to solve the issue of multi-spectral radiative property parameters of high-porosity materials at high-temperature, and the transient coupled transfer mechanism of multi-spectral thermal radiation, heat conduction and convection will be revealed in the two scales of continuum level and pore level. And finally, the influence rule of the material properties and the pore structure characteristics on the high-temperature energy transport in the materials will be obtained. This research can provide thermal physics foundation support for the design, high-temperature application and innovative development of related technologies of porous materials. It can also promote the development of related disciplines, including thermal physics and energy use as well as aerospace, and others.

高孔隙率材料在太阳能高温利用、高温强化换热、高温热防护等领域有广泛的应用需求和发展前景。本项目以这些技术领域中共性的高孔隙材料内高密度能量转换与高温输运过程为对象，研究其光谱辐射能的传递机理及与热传递的耦合特性。. 主要内容包括：泡沫材料内孔隙尺度的光谱辐射传递机理与特性、材料高温辐射特性参数的实验测量方法、材料内热辐射传递与导热－对流高温热传递的瞬态耦合性。. 通过研究，建立此类材料孔隙尺度光谱辐射传递的分析方法，揭示其热辐射传递机理；掌握材料的高温辐射特性参数实验方法与技术，实现材料的介质辐射特性参数测量与理论预测；获得高能流密度辐射传递与高温热传递的耦合特性。从而解决高孔隙率材料在能量高温转换与输运技术应用中的关键热科学问题，为相关技术的创新发展提供基础支撑，促进相关学科的交叉发展。

泡沫等高孔隙材料，在能量高温转换和传递、飞行器热防护等技术领域有重要的应用需求和发展前景。泡沫材料高温辐射光谱的多尺度耦合传输机理、高孔隙材料的高温光谱辐射特性参数获取方法，是制约此类材料相关技术创新发展的关键热科学问题。.本项目围绕上述两个关键热科学问题，开展了以下三方面研究。(1)泡沫材料孔隙结构光谱辐射传输的多尺度耦合机理建模；(2)孔隙材料高温光谱辐射特性参数的实验测量方法与技术；(3)孔隙材料高温辐射与导热、对流的双尺度瞬态耦合传输特性。.针对金属和陶瓷两类基材辐射和孔隙结构特征不同的泡沫材料，通过对镍、氧化铝等真实泡沫材料微细观结构的μ-CT和SEM扫描重建、微尺度和孔隙尺度的辐射传输求解，系统分析了两类泡沫的骨架微结构光谱辐射特性、孔隙结构细观光谱辐射传输机理和特性。建立了从骨架微结构到孔隙结构、从孔隙到泡沫连续介质层次的光谱辐射传输跨尺度耦合分析方法，开发了计算源代码。研究了材料和微细观参数对其高温光谱辐射特性的影响规律，揭示了两类泡沫材料中光谱辐射传输的多尺度耦合机理。.从样件表观辐射特性的等温测量、传热过程瞬态特性测量两条途径，探索了孔隙材料高温光谱辐射特性参数的实验获取方法。研制了表观辐射特性测量（2000K）、瞬态传热特性测量（2300K）两种实验装置，建立了参数辨识方法。获得了国产镍泡沫、Al2O3块材（蓝宝石）与泡沫、陶瓷隔热瓦等材料的高温辐射特性数据。.针对泡沫材料中高温辐射-导热、辐射-对流两类耦合传输问题，分别构建了孔隙尺度与连续介质模拟相结合的双尺度分析方法，开发了计算源代码。结合应用，研究了两类高孔隙材料中的辐射-对流、辐射-导热高温耦合输运特性。.已发表论文112篇，其中，SCI收录72篇，SCI他引286次；授权发明专利9项，登记软件著作权6项。这些研究成果将为相关材料的高温应用和技术创新提供有力的热学理论指导和基础支撑。