Session
Weekday Session 11: Advanced Technologies II
Location
Utah State University, Logan, UT
Abstract
Advanced Cooling Technologies has been developing 3D printed loop heat pipes as low-cost, rapidly-manufacturable alternatives to standard loop heat pipes. With 3D printing, the evaporator build can be entirely automated leading to significant savings in costs and lead times. The 3D printed loop heat pipe can enable high-performance small satellites with significant enhancement of the heat rejection capability. This paper provides a comprehensive narrative of the 3D printed loop heat pipe development, including an exposition of the wick and evaporator development, and a discussion of select test results acquired in the laboratory. The evaporator wick was achieved by carefully controlling the build parameters in laser powder bed fusion to force incomplete melting of the stainless-steel powder. The evaporator was developed as a single bi-porous part, containing a wick section that is surrounded by an annular wall, requiring zero post-build assembly. The 3D printed loop heat pipes were successfully operated in the laboratory with both propylene and ammonia, including at a heat load of over 300 W with the latter working fluid. A purpose-built propylene 3D printed loop heat pipe for NASA’s VIPER EDU was also demonstrated successfully, leading to a TRL 6 advancement for the technology.
3D Printed Loop Heat Pipes for High-Performance Small Satellites
Utah State University, Logan, UT
Advanced Cooling Technologies has been developing 3D printed loop heat pipes as low-cost, rapidly-manufacturable alternatives to standard loop heat pipes. With 3D printing, the evaporator build can be entirely automated leading to significant savings in costs and lead times. The 3D printed loop heat pipe can enable high-performance small satellites with significant enhancement of the heat rejection capability. This paper provides a comprehensive narrative of the 3D printed loop heat pipe development, including an exposition of the wick and evaporator development, and a discussion of select test results acquired in the laboratory. The evaporator wick was achieved by carefully controlling the build parameters in laser powder bed fusion to force incomplete melting of the stainless-steel powder. The evaporator was developed as a single bi-porous part, containing a wick section that is surrounded by an annular wall, requiring zero post-build assembly. The 3D printed loop heat pipes were successfully operated in the laboratory with both propylene and ammonia, including at a heat load of over 300 W with the latter working fluid. A purpose-built propylene 3D printed loop heat pipe for NASA’s VIPER EDU was also demonstrated successfully, leading to a TRL 6 advancement for the technology.
