Study on transferring the refrigeration power in the temperature-distributed regenerative refrigeration cycle

The temperature-distributed regenerative refrigeration cycle utilizes the real-gas properties to generate the temperature-distributed refrigeration power and improves the cooling performance and liquefaction rate of cryogenic gases. The temperature-distributed refrigeration power is distributed in the volume of the regenerator. It is challenging to transfer this distributed refrigeration power, and the regenerative heat loss is usually inevitable. The transfer process of the temperature-distributed refrigeration power is studied in this paper. A comprehensive investigation into associated influencing factors is presented in this paper. Furthermore, a parameter of the temperature-distributed transfer coefficient (TTC) is proposed to evaluate the transfer process. This study extends into a broader range of the discrete transfer method from liquid-helium temperatures to ambient temperatures and further analyzes the rules from scattered points to multiple points. The internal DC flow method is adopted to eliminate the radial thermal resistance and improve the TTC, recognizing the constraints of the traditional distributed transfer method (coiling heat exchange tubes outside the regenerator). The TTC of the distributed method with the DC flow is improved around 1-2 times by optimizing the mass flux of multi-strand DC flow and temperature range. It is also improved 1.5-2 times by combining the DC flow and discrete method. Additionally, the TTC is improved about 1-1.5 times with the DC flow when using the refrigeration power for gas liquefaction.