Experimental characterization of an innovative refrigeration system coupled with Linde-Hampson cycle and auto-cascade cycle for multi-stage refrigeration temperature applications

In this study, a dual mixed-refrigerants refrigeration system coupled with a Linde-Hampson refrigeration (LHR) cycle and a three-stage auto-cascade refrigeration (ACR) cycle was designed and built. The thermodynamic performance of the coupled system was experimentally investigated using low GWP zeotropic mixtures of R1234yf/R32 for the LHR and R170/R14/R50 for the ACR. The experimental results show that when the average ambient temperature was 24.18 degrees C, it took about 0.5 h for the prototype to reach a no-load temperature level of -120 degrees C, and 4 h to -146.97 degrees C, which was quite close to steady state. The corresponding cooling capacity, coefficient of performance (COP) and relative Carnot efficiency were 182.94 W, 0.121 and 16.0%, respectively. The hot fluid outlet temperatures in the condensation evaporator-I (CE-I), CE-II and CE-III were -49.04 degrees C, -87.12 degrees C and -113.20 degrees C, respectively. In addition, the discharge pressure, evaporation temperature and cooling capacity increased slightly with increasing ambient temperature, while the suction pressure and COP remained nearly constant. The LHR-ACR system manifests a promising perspective as a new cooling approach to produce multi-temperatures ranging from -40 degrees C to -150 degrees C in the energy cascade utilization fields, such as the multi-temperature cryopreservation and gas liquefaction. (C) 2021 Elsevier Ltd. All rights reserved.