Effects of porosity and wire diameter on pressure drop and heat transfer characteristics of sintered metal fiber

Abstract

Regenerator is the indispensable regenerative heat exchanger in Stirling cycle machines. The existence is the key factor so that Stirling cycle may have the highest thermal efficiency. Regenerator matrices are often made of the stacks of high mesh size wire gauzes, because of the optimum balance between flow loss and heat transfer characteristics. However, the matrix made of stacked wire gauzes is high cost. So, SMF (sintered metal fiber) is suggested as a new matrix. In this report, the basic characteristics of pressure drop and heat transfer are measured using steady flow experimental apparatus. The experiment results are reduced in the empirical equations between the friction factor and Reynolds number, and between f the Nusselt and Reynolds number.