超临界压力流体在多孔介质内对流换热研究进展

超临界压力流体在多孔介质内的流动换热问题在动力工程、化学工程、航天航空等领域的应用非常广泛,它是超临界CO_2气冷堆、太阳能热发电系统、超临界压力流体对高温壁面的发汗冷却等工程设计优化的理论基础。分别从实验研究和数值模拟两个方面,详细阐述了多孔介质内超临界压力流体流动换热的研究进展,指出了准临界温度附近强烈物性变化、多孔结构迂曲流动通道、浮升力等因素对换热通道局部对流换热性能的影响规律是深入研究的关键问题。另外由于高温高压实验难度大、数据处理方法较复杂,多孔介质内超临界压力流体与固体骨架之间的内部对流换热系数实验研究非常少,致使局部非热平衡模型在多孔介质内超临界压力流体流动换热数值模拟的应用受到限制,因此同时加强超临界压力流体在多孔介质内流动传热的局部对流换热性能和内部对流换热性能研究,对于多孔介质结构传热性能评价和工业应用关键设备的设计优化具有指导意义。

Research Progress on Convection Heat Transfer of Supercritical Pressure fluid in Porous Media

Convection heat transfer of supercritical pressure in porous media is widely used in power engineering, chemical engineering, aerospace and other fields. It is the theoretical basis for engineering design optimization of supercritical CO2 gas-cooled reactor, solar thermal power generation system and transpiration cooling of high temperature wall. In this paper, the research progress of supercritical pressure fluid flow and heat transfer in porous media is described in detail from experimental research and numerical simulation. It is pointed out that the effects of strong physical property variations near the pseudo-critical temperature, tortuous porous structure, buoyancy on the local convective heat transfer performance are for further research. In addition, due to the difficulty of high temperature and high pressure experiments and the complexity of data processing methods, the experimental study on the internal convection heat transfer coefficient between supercritical pressure fluid and solid skeleton in porous media is very few. It limits the application of local non-thermal equilibrium model in numerical simulations. Therefore, the local and internal convection heat transfer performance of supercritical pressure fluid flow and heat transfer in porous media are very significant for heat transfer performance evaluation of porous media structure and design optimization of key equipment for industrial applications.