受限孔隙空间气体-颗粒两相微尺度流动与复合传热机理研究

With combined utilization of theoretical analysis, numerical modeling and experimental exploration, a thorough and systematic investigation will be carried out in this project on the crucial scientific issues of the micro-scale gas-particle fluid flow and combined heat transfer in confined pore space in micro porous media combustor. The main work includes: 1) exploring the mechanical action of solid particle in micro gas phase, revealing the multi-scale particle dynamic behavior and the non-equilibrium momentum exchange between gas and particle with the influence of rarefaction effect; 2) exploring micro-scale quantitative mechanism of interaction among gas, particle and wall, establishing the trans-scale numerical model for gas-particle two-phase flow, and revealing the flow characteristic in the confined pore space; 3) revealing the characteristic of gas-particle two-phase convection heat transfer in micro pore space and the multi-scale radiation heat transfer of micro/nano particles, developing the theoretical model for the coupled convection-radiation heat transfer of gas-particle two-phase fluid; 4) exploring the law of coupled conduction-radiation heat transfer of porous skeleton with the reconstruction of porous geometry, revealing the combined heat transfer mechanism of coupled convection-radiation-conduction heat transfer of gas-particle two-phase fluid in micro porous media. Based on the above investigation, the theoretical system for gas-particle two-phase flow and heat transfer in micro scale will be established. It can enrich the scientific system of micro-scale gas-solid multiphase flow, guide the design and development of new-type and efficient micro porous media combustor, and thus is of significant scientific value.

本项目拟结合理论分析、数值模拟与实验探索，围绕微多孔介质燃烧室受限孔隙空间内气体-颗粒两相微尺度流动传热过程中的关键科学问题开展深入系统研究，内容包括：1）从微气体中颗粒力学作用出发探究颗粒多尺度运动行为特征，定量揭示稀薄效应下气体-颗粒间动量非平衡传递机制；2）研究微尺度气体-颗粒-壁面间相互作用量化规律，构建气粒两相流跨尺度模拟数理模型，掌握受限孔隙空间中气粒两相流动行为特性；3）全面准确揭示微孔隙流道内气粒两相对流传热以及微纳颗粒辐射能量的多尺度传递行为规律，构建微尺度气粒两相对流-辐射耦合传热理论模型；4）探究基于三维真实几何结构数值重建的多孔骨架导热-辐射热量耦合传递规律，揭示多孔介质内气粒两相微尺度对流-辐射-导热复合热量传递机制。通过上述研究，旨在构建系统完整的微尺度气粒流动传热理论，完善和发展微尺度气固多相流科学体系，指导高效微多孔介质燃烧室的设计开发，具有重要科学意义。

本项目基于我国系统微型化领域对微型能源动力系统发展的迫切需求，针对当前微尺度气体-颗粒两相在微多孔介质燃烧室中输运遇到的关键问题，围绕受限孔隙空间中气体-颗粒-骨架相互作用的流动传热机理，系统深入地开展了理论分析、数值模拟与实验研究，内容包括：1）从微气体中颗粒力学作用出发探究颗粒多尺度运动行为特征，提出了滑移区曲边界格子Boltzmann（LB）处理新格式，构建了微尺度有限体积多颗粒运动LB模型，定量揭示了稀薄效应下气体-颗粒间动量非平衡传递机制；2）构建了基于气-粒双向耦合的DPM点源颗粒微尺度气粒两相流动传热数理模型，计算分析不同尺寸与形状微孔隙通道中气粒两相流体流动传热过程，研究了气体微尺度效应与壁面作用对受限空间中气粒两相流动传热影响程度，提出了微尺度气体-颗粒-壁面间相互作用量化规律，掌握了受限孔隙空间中气粒两相流动行为特性；3）构建了颗粒-颗粒间近场热辐射计算模型，分析了颗粒尺寸/间距对颗粒-颗粒间近场辐射换热的影响规律，构建了微尺度气粒两相对流-辐射耦合传热数值模型，全面准确揭示了微孔隙流道内气粒两相对流传热以及微纳颗粒辐射能量的多尺度传递行为规律；4）构建了多孔介质真实三维结构数值模型，计算分析复杂孔隙结构中气体流动传热过程，获得了多孔骨架结构、孔隙形状、热边界条件等对受限孔隙空间内气粒流动传热的影响特性，揭示了多孔骨架导热-辐射热量耦合传递规律，掌握了多孔介质内气粒两相微尺度对流-辐射-导热复合热量传递机制。通过上述研究，完善了微尺度气粒流动传热理论，进一步发展了微尺度气固多相流科学体系，本项目成果可为高效微多孔介质燃烧室的设计开发提供指导，具有重要科学意义。