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Force-System Resultants and Equilibrium
Published in Richard C. Dorf, The Engineering Handbook, 2018
The pulse tube refrigerator consists of a compressor with a rotating valve distributor (or a source of pressure oscillation), a regenerator for heat exchange, and the pulse tube. The pulse tube is connected at the ambient temperature end to a buffer volume through an orifice, needle valve, or other suitable flow resistance element. High-pressure gas enters the regenerator, in which the gas is cooled. The cold gas leaving the regenerator enters the pulse tube at the cold end and acts as a gas piston to compress the gas already within the pulse tube. The compressed gas flows through the pulse tube to the warm end, where the gas is cooled by exchanging energy in an ambient-temperature heat exchanger. The rotary valve is turned such that the gas inlet is closed, the exhaust is opened, and the cooled gas in the pulse tube expands and experiences a decrease in temperature. The expanding gas flows back through the pulse tube, absorbs energy from the region to be refrigerated, and leaves the system through the regenerator.
Numerical investigation of a displacer-type pulse tube refrigerator with work recovery
Published in Science and Technology for the Built Environment, 2022
Wenhu Duan, PU Zheng, Yankang Wu, Jingru Zhan, XI Chen
The pulse tube refrigerator with low vibration plays a significant role in various high-reliability fields such as liquefaction of gases (Hu et al. 2016) and the cooling of infrared detectors (Deng et al. 2020a). Since the basic pulse tube refrigerator is invented by Gifford and Longsworth (1964), a series of breakthroughs in structure have been made, including the invention of the orifice pulse tube refrigerator (Mikulin, Tarasov, and Shkrebyonock 1984), the double inlet pulse tube refrigerator (Zhu, Wu, and Chen 1990), and the inertance tube pulse tube refrigerator (ITPTR) (Kanao, Watanabe, and Kanazawa 1994). Among the pulse tube refrigerators mentioned above, the ITPTR is the most popular for its high efficiency. However, the theoretical efficiency of the ITPTR is still lower than that of the Stirling refrigerator because the acoustic power at the hot end is dissipated by the phase shifter in the form of heat. To tackle this problem, several new structures are proposed, such as cascade-type WRPTR (K. Wang et al. 2016) and displacer-type WRPTR. The latter, which can be easily obtained by modifying an existing ITPTR, has received extensive attention from researchers.
Multi-objective optimisation of thermodynamic performance parameters of a Gifford-McMahon refrigerator
Published in International Journal of Ambient Energy, 2022
Debashis Panda, Ashok K. Satapathy, Sunil K. Sarangi
Thus, in an electric vehicle a cooling arrangement, a vacuum chamber, and an HTS motor have been adopted to reduce the power consumption by a factor of 20% in comparison with conventional motors. Some commercial organisations like ‘Sumitomo Electric Industries’ (SEI) have already developed such compact HTS motors for electric vehicles since 2013 with a project grant from ‘New Energy and Industrial Technology Development Organization’ (NEDO). The cryogenic division of SHI group develops the cooling system for the project. A pulse tube refrigerator developed by Nakano et al. (Ishizuka et al. 2011; Nakano, Yumoto, and Hiratsuka 2015) is used for the cooling purpose of HTS motors because of its compact size in an electric car.