Study on Liquid Nitrogen Gravity Circulation Loop for Cryopumps in Large Space Simulator

Authors: Weiwei Shan, Wenjing Ding, Juan Ning, Chao He, Zijuan Wang

Abstract:

Gravity circulation loop for the cryopumps of the space simulator is introduced, and two phase mathematic model of flow heat transfer is analyzed as well. Based on this model, the liquid nitrogen (LN₂) gravity circulation loop including its equipment and layout is designed and has served as LN₂ feeding system for cryopumps in one large space simulator. With the help of control software and human machine interface, this system can be operated flexibly, simply, and automatically under four conditions. When running this system, the results show that the cryopumps can be cooled down and maintained under the required temperature, 120 K.

Keywords: Cryopumps, gravity circulation loop, liquid nitrogen, two-phase.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1132395

References:

[1] Shanweiwei. A study on the method of nitrogen gravity fed system design. Spacecraft environment engineering, 2013, 12.
[2] Liubotao. Discussion on LN2 gravity fed system in the space simulator (J). 2003 Cryogenics conference，2003，123-127
[3] DmitriyPodkorytov, Leonid Timkin, Vladimir Chechovich, The investigation of flow characteristics and heat transfer at the nitrogen natural circulation in capillary, Cryogenics, Volume 32, Supplement 1, 1992, Pages 316-319.
[4] Yeon Suk Choi, Ho-Myung Chang, Steven W. Van Sciver, Performance of extended surface from a cryocooler for subcooling liquid nitrogen by natural convection, Cryogenics, Volume 46, Issue 5, May 2006, Pages 396-402.
[5] Kim, M. J., Chang, H. M., Natural circulation loop of subcooled liquid nitrogen, Weisend, JG; Barclay, J; Breon, S; Joint Cryogenic Engineering Conference/International Cryogenic Materials Conference, Chattanooga, TN, Jul 16-20,2007, Advances in Cryogenic Engineering, Vols 53A and 53B, AIP Conference Proceedings, 985 2008:59-66.
[6] Chang, Ho-Myung; Kim, Min-Jee; Sim, Jung Wook, A compact cryocooling system with subcooled liquid nitrogen for small HTS magnets, 20th International Conference on Magnet Technology, Philadelphia, PA, AUG27-31,2007, IEEE Transactions on Applied Superconductivity, 2008, 18(2):1479-1482, DOL: 10.1109/TASC.2008.920553.
[7] Baudouy, B., Experimental study of a nitrogen natural circulation loop at low heat flux, Weisend, JG; Barclay ,J; Breon, S; Joint Cryogenic Engineering Conference/International Cryogenic Materials Conference, Tucson, AZ, JUN28-JUL02,2009, Advances in Cryogenic Engineering, Vols 55A and 55B, AIP Conference Proceedings, 2010,1218:1546-1553 DOL:10.1063/1.3422335.
[8] Yu. Ivanov,A. Radovinsky, A. Sasaki,H. Watanabe, T. Kawahara, and S.Yamaguchi, A compact cooling system for HTS power cable based on thermal siphon for circulation of LN2, AIP Conference Proceedings 1218, 865(2010);doi:10.1063/1.3422441.
[9] Yamaguchi, Satarou;Ivanov, Yury; Sun,Jian, Experiment of the 200-meter superconducting DC transmission power cable in Chubu University, Kes, PH; Rogalla, H, Superconductivity Centennial Conference (SCC): Hague, Netherlands: Sep18-23,2011: Superconductivity Centennial Conference 2011: Physics Procedia, 2012,36:1131-1136 DOI :10.1016/j.phpro.2012.06.189.
[10] Yury Ivanov, Hirofumi Watanabe, Makoto Hamabe, Toshio Kawahara, Jian Sun, Satarou Yamaguchi, Observation of the thermo siphon effect in the circulation of liquid nitrogen in HTS cable cooling system, Physics Procedia, Volume 27,2012, Pages 368-371.
[11] Hisashi Umekawa, Mamoru Ozawa, Toshiaki Yano, Boiling two-phase heat transfer of LN2 downward flow in pipe, Experimental Thermal and Fluid Science, Volume 26, Issues 6-7, August 2002,Pages 627-633.
[12] V. V. Klimenko, A. M. Sudarchikov. Investigation of forced flow boiling of nitrogen in a long vertical tube. Cryogenics, 1983,23 (7):379-385.
[13] Luzhongqi. Two-phase flow and boiling heat transfer. Tsinghua press, 2002.