Integrated Hot Reservoir Variable Conductance Heat Pipe with Improved Reliability



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51st International Conference on Environmental Systems


A hot reservoir variable conductance heat pipe (VCHP) that can offer tight and passive thermal control is an ideal thermal link for future planetary landers and rovers. This is especially useful for the moon operation as surviving during the lunar night is energetically challenging. Under a Small Business Technology Transfer (STTR) program, Advanced Cooling Technologies (ACT) and Case Western Reserve University (CWRU) developed an advanced integrated hot reservoir VCHP with improved reliability. This novel design enables a momentum-induced flow to circulate through a non-condensable gas (NCG) loop, which can continuously and effectively remove the excessive working fluid vapor from the reservoir (i.e. purging) without using an electric heater. Based on the purging test results, the bulk induced flow velocity is in a cm per second range. Without the flow, purging is dominated by diffusion and it will take hours to complete. With momentum-induced flow, the purging rate is much faster and the heat pipe can get back to normal operation within 20 minutes. This paper summarizes prototype development and experimental study of hot reservoir VCHP loop, including a detailed analysis of the VCHP purging process, purging, and startup testing of VCHP loop. A compact hot reservoir VCHP loop prototype with both reservoir and NCG tube integrated was developed and tested.


Kuan-Lin Lee, Advanced Cooling Technologies,Inc., US
Calin Tarau, Advanced Cooling Technologies,Inc., US
William Anderson, Advanced Cooling Technologies,Inc., US
Cho-Ning Huang, Case Western Reserve University, US
Chirag Kharangate, Case Western Reserve University, US
Yasuhiro Kamotani, Case Western Reserve University, US
ICES104: Advances in Thermal Control Technology
The 51st International Conference on Environmental Systems was held in Saint Paul, Minnesota, US, on 10 July 2022 through 14 July 2022.


Variable Conductance Heat Pipe, Planetary Lander Thermal Management, Fluid Management