Investigation of liquid-vapor flow and heat transfer in porous media.

摘要

By combining two-phase heat transfer with forced convective flow through a porous material, a new heat transfer scheme emerges with the ability to absorb high heat fluxes without the corresponding temperature increase encountered in single phase systems. This new system exhibits thermal behavior characteristic of liquid metal flow cooling systems. Although a limited amount of work has been done on single phase heat transfer in porous metallic materials, the area of two-phase heat transfer in metallic porous materials has received little or no attention as determined from an extensive literature review.;To predict the heat transfer attributes of the system, a semi-analytical model was developed using the conservation equations of mass, momentum and energy along with the apparent physical properties of the composite material. The results indicate that when a heat flux is applied to one side of the bounding surface and adiabatic conditions exist on the remaining sides, the surface temperature asymptotically approaches a the same value regardless of the mass flow rate. Verification of the model with different materials and geometries is demonstrated along with a number of detailed analysis, and a new non-dimensionalized method for predicting the thermophysical behavior of these systems.