Experimentally validated analytical expressions for the thermal resistance of a novel composite fin-foam annular array

Novel expressions are developed for the thermal resistance associated with an array consisting of periodic layers of metal fins and open-cell, high porosity metal foam attached annularly to a base cylinder. Predictions generated with the new expressions are verified by comparison with experimental measurements involving such an array and a cylindrical heat pipe. Parametric simulations are performed to assess the performance of the array over a range of geometric configurations, thermal contact resistances, and air velocities. Analytically predicted heat rates for an annular fin array, a foam-only annular array, and the new combined fin-foam array are compared, illustrating the improved thermal performance made possible by combining metal fins and foam into a composite array.