3D-printed heat pipe array for fusion

A commercial magnetic nuclear fusion reactor is expected to produce local heat fluxes up to 20 MW/m2, and conventional cooling methods will likely not suffice. A 3D-printed heat pipe array is proposed to be placed in these high heat flux areas. In this report the feasibility of such heat pipe array is investigated by picking one heat pipe out of it and determining its critical heat flux. Two heat pipes have been successfully produced and prepared for operation. They were tested up to a heat flux of 1.0±0.2 MW/m2. Higher heat fluxes could not be obtained due to limitations of the experimental setup. Under this heat flux, two-phase operation has been observed and the heat pipes did not dry-out even with the heat pipe oriented against gravity. This demonstrates the functionality of the heat pipe. The heat pipe design has been modified to allow higher heat fluxes to be tested, and as the functionality was already demonstrated, a design of experiments was implemented as well and 13 new heat pipes have been produced. They new design has shown that it can absorb heat fluxes over 10 MW/m2, but the heat pipes have not yet been prepared for operation. Once they are prepared and tested, the results will be appended to this report.