Test results from a pumped single-phase porous metal heat exchanger

A pumped single-phase porous metal cooled microwave cavity design is being evaluated for use in a high-power gyrotron. A small-scale porous metal cooled test article was designed, built, and tested on a Phase I SBIR program. The program was funded by the United States Department of Energy. A copper/water porous metal heat exchanger test article was fabricated and was subsequently tested at absorbed heat fluxes up to 7.4 +/- 0.3 kW/cm2 before failure occurred. Multiple tests were successfully completed at heat fluxes of 4.0 to over 6.0 W/cm2 with no signs of failure. The test article design, coolant parameters, test methodology, and test results are presented. The results of this work show the potential of porous metal cooling to solve a number of high heat flux cooling problems; several such applications are described.