Experimental investigation on an oil-cooled auto-cascade refrigeration system for aircraft.

The cooling requirements of new-generation airborne devices, coupled with the demand for extended endurance of aircraft under high heat loads, impose higher performance requirements on airborne vapor compression refrigeration systems operating under large temperature differences. Auto-cascade refrigeration system shows significant advantages in this application domain. However, there is little research within the relevant temperature range, especially experimental studies. To address the need for large-temperature-difference cooling in aircraft, this paper firstly presents the experimental investigation of an auto-cascade refrigeration system for aircraft using R245fa/R134a as the refrigerant with a heat source temperature of 20 ◦C and heat sink temperatures ranging from 55 ◦C to 100 ◦C. The effects of refrigerant charge, mixed refrigerant concentration, heat sink temperature, and valve opening on the performance were analyzed. The results can help the design of future aircraft refrigeration systems and promote the application of auto-cascade refrigeration in higher temperature range.