Abstract
Helium pulsating heat pipes (PHPs) are an emergent heat transfer technology that can provide efficient, long-distance cooling power for numerous low-temperature technologies, such as superconducting magnets and space telescopes. An experimental facility is developed to test the performance of a vertically oriented helium PHP with an adiabatic length of 1.25 m. The PHP in these experiments consists of 14 parallel stainless-steel tubes with an inner diameter of 0.5 mm. Each end of the pulsating heat pipe is fixed to a thin copper plate where the condenser (upper) end is cooled by a 4 K cryocooler with a 1.5 W cooling capacity, while a resistive heater provides a prescribed heat load to the evaporator (lower) end. Progressive heat load experiments were performed for fill ratios 37.3% and 70.78%, from which phase and flow regime information at multiple locations is predicted. The maximum performances for each test were 273 kW/m-K at 0.23 W and 136 kW/m-K at 0.43 W for the 37.3% and 70.78% fill ratios, respectively.
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References
Khandekar, S.: Thermo-hydrodynamics of closed loop pulsating heat pipes. Dr.-Ing dissertation. University of Stuttgart (2004)
Akachi, H.: Structure of a heat pipe. U.S. Patent No. 4921041 (1990)
Fonseca, L.: Experimental characterization of cryogenic helium pulsating heat pipes. Ph.D. dissertation, University of Wisconsin – Madison (2016)
Fonseca, L., Pfotenhauer, J., Miller, F.: Short communication: thermal performance of a cryogenic helium pulsating heat pipe with three evaporator sections. Int. J. Heat Mass Transf. 123, 655–56 (2018)
Ortiz-Vega, D.: A new wide range equation of state for helium-4. Ph.D. dissertation, Texas A&M University (2013)
Xue, Z., Qu, W.: Experimental and theoretical research on a ammonia pulsating heat pipe: new full visualization of flow pattern and operating mechanism study. Int. J. Heat Mass Transf. 106, 149–66 (2017)
Karthikeyan, V., Khandekar, S., et. al.: Infrared thermography of a pulsating heat pipe: flow regimes and multiple steady states. Appl. Therm. Eng. 62, 470–80 (2014)
Li, M., Li, L., Xu, D.: Effect of filling ratio and orientation on the performance of a multiple turns helium pulsating heat pipe. Cryogenics 100, 62–68 (2019)
Acknowledgments
This work was supported by a NASA Space Technology Graduate Research Opportunities Award.
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Kossel, L., Pfotenhauer, J., Miller, F. (2023). The Effect of Fill Ratio on the Performance and Flow Regime for Long-Distance Helium Pulsating Heat Pipes. In: Qiu, L., Wang, K., Ma, Y. (eds) Proceedings of the 28th International Cryogenic Engineering Conference and International Cryogenic Materials Conference 2022. ICEC28-ICMC 2022. Advanced Topics in Science and Technology in China, vol 70. Springer, Singapore. https://doi.org/10.1007/978-981-99-6128-3_56
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DOI: https://doi.org/10.1007/978-981-99-6128-3_56
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