Abstract
This paper describes the heat transfer and flow characteristics of a heat exchanger tube with high porous material. Copper wire was inserted in a tube. The porosity was from 0.98 to 1.0. Working fluid was air. Hydraulic equivalent diameter was cited as the characteristic length in Nusselt number and Reynolds number. Nusselt number and friction factor were evaluated as functions of Reynolds number based on hydraulic equivalent diameter and porosity. Thermal performance was examined by the ratio of Nusselt number with and without porous material at constant pumping power. The porosity which gave the maximum thermal performance was found by extending the allowable region.
