微/纳米双孔分布多孔介质耦合换热关联机制及异质界面热质传递

Deepen acquaintance on heat and mass transfer mechanism in micro/nano meter dual-porosity distributed media is very important for exploitation and application extension of related materials. This project is to study the coupled and correlative heat transfer mechanism in dual-porosity distributed materials and the interaction heat and mass transfer process at the heterogenous interface in confined nano-structures by expanding the existed theoretial and experimental methods. Theoretically, the kinetic theory of gases are adopted to describe and analyze the heat and mass transfer similarities and differences in different scale of porous materials and their correlative mechanism. The improved molecular dynamics simulation method is adopted to analyze heat and mass transfer interaction process at the heterogenous interface in confined nano-structures, and discuss the influence characteristics of the confined nano-porous structures, solid framework, the nano-pore connectivity, as well as ambient temperature, pressure on heat and mass transfer process at the heterogenous interface, analyze the coupled heat transfer performance at the confined heterogenous interface under the heat treatment and clipping regulation conditions. Experimentally, the thermal conductivity of micro/nano meter dual-porosity distributed porous materials will be measured at different pressures and at different filling gases conditions. The thermophysical property data and the variation patterns of the dual-porosity distributed porous materials will be got, and be used to compare with the theoretical research results. The research will deepen the recognization of heat and mass transfer process in micro/nano meter dual-porosity porous media and heterogenous interface in the confined nano-structures.

深化对微/纳米双孔分布多孔介质内部热质传递规律的认识对于相关材料的进一步开发和推广应用意义重大。本项目通过拓展现有理论和实验方法，研究微/纳米双孔分布多孔介质内部的耦合换热关联机制及纳米孔隙受限空间内异质界面热质传递规律。理论上，采用气体分子运动论思想探讨不同量级孔隙材料内部热质传递规律的异同及关联特性，基于改进的分子动力学模拟方法分析纳米尺度受限空间内异质界面的热质传递交互作用，探讨纳米尺度受限空间内孔隙结构、固体骨架特征、纳米孔连通性，以及环境温度、压力等因素对异质界面热质传递规律的影响，分析热处理温度、剪裁调控机制下纳米孔隙内部异质界面耦合换热特性。实验方面，通过不同压力及不同填充气氛下热导率的测量，得到微/纳米双孔分布材料的热物性数据及其变化规律，并与理论研究结果进行对比。本项目将深化对微/纳米双孔分布介质及受限空间内异质界面热质传递规律的认识。

本项目通过拓展现有理论和实验方法，研究微/纳米双孔分布多孔介质内部的耦合换热关联机制及纳米孔隙受限空间内异质界面热质传递规律。通过分子动力学模拟，传热模型的构建以及材料热导率的测量，深入揭示了微/纳米双孔分布材料内的耦合换热关联机制。对纳米孔隙内的典型气体分子运动特性进行了分析和模拟，得到气体分子在此受限空间内的运动规律以及气体分子与固体壁面间的交互作用规律。采用单元体传热思想建立了微/纳米双孔分布介质的气-固耦合换热关联机制模型，深化了对微/纳米双孔分布材料内部热质传递机理的认识。对影响微/纳米双孔分布介质热物性参数的关键因素进行了深入讨论，得到了不温度、不同填充气体状态下微/纳米双孔分布材料热导率随环境压力的变化规律。通过材料热物性参数的测量，积累了微/纳米双孔分布材料的热物性数据，并为理论模型及换热机理的揭示提供了必要的验证数据。