2021-06-242021-06-247/12/2021ICES-2021-154https://hdl.handle.net/2346/87128Rohit Gupta, Advanced Cooling Technologies, Inc.Chien-Hua Chen, Advanced Cooling Technologies, Inc.William Anderson, Advanced Cooling Technologies, Inc.ICES201: Two-Phase Thermal Control TechnologyThe 50th International Conference on Environmental Systems was held virtually on 12 July 2021 through 14 July 2021.The rapid growth of the miniaturized satellite industry has led to increased demand for low-cost and robust thermal management systems. Advanced Cooling Technologies, Inc. has been developing Loop Heat Pipes with 3D printed evaporators in an effort to reduce manufacturing costs and lead times by eliminating labor-intensive processes that are otherwise involved in the fabrication of standard evaporators. These processes include, but are not limited to, the primary wick fabrication, wick insertion, and knife-edge seal. The reported work describes the latest progress in this technology in the areas of primary wick advancement and thermal performance improvement. Following iterative optimization in this work, the pore size of the 3D printed wick was reduced to a sub-5-micron level, with a maximum radius of 4.9 ?m. A new evaporator was 3D printed, featuring a refined primary wick and a fully-dense front wall, in order to prevent vapors from the vapor plenum being forced back into the evaporator under strong adverse pressure gradients. The overall thermal conductance of the system was improved by over 15% by incorporating a new saddle design with a single, connected structure and featuring a horizontal clamping mechanism. The new 3D printed evaporator assembly was also shown to operate successfully at a steady state power level of 350 W using line tubing with diameter of 0.003 m and ammonia as the working fluid.application/pdfengLoop Heat PipeDirect Metal Laser Sintering3D PrintingAdditive ManufacturingHot Isostatic PressingPresentation