How Good Is Open-Cell Metal Foam as Heat Transfer Surface?

High porosity open-cell metal foam is considered to be an attractive choice for compact heat exchanger applications because of its high area density and superior thermal performance. A systematic study has been made in the present article to verify the suitability of the porous material as an extended heat transfer surface. The area goodness (j/f) factor has been chosen as performance evaluation criterion. This governing parameter has been computed using the existing correlations for the heat transfer and pressure drop coefficients. Conservative estimate shows that the thermohydraulic characteristics of high porosity open-cell metal foam are almost alike, if not better than those of the conventional heat transfer surfaces. Importantly, the analysis has been found to be consistent with the Reynolds analogy. This study helps the designer in making the initial selection of foam surfaces for the heat exchanger application.