Abstract: Unlike household scenarios, the vehicle refrigerator compressor operating in a mobile environment can cause a deterioration in oil discharge, which can have adverse effects on the system. A study was conducted on the effect of a muffler on the oil discharge volume, as the refrigerant oil enters the cylinder through the muffler during inclined operation of the compressor. The oil volume with 65 mL is firstly determined as the research object to study the influence of the muffler on the oil discharge for vehicle refrigerator compressor. Based on the experimental analysis of horizontal and inclining at the different structures, the effect and mechanism of the muffler oil leakage hole are further revealed with numerical simulation. The results show that there is negative pressure inside the muffler during the suction process, and the oil would be sucked in quickly when the leakage hole touches the oil surface. The maximum oil discharge could reach 25.8 mL/h, and the amount of oil discharge decreases to zero after the leakage hole is removed. Ultimately got the best solution for the oil discharge problem of the vehicle refrigerator compressors wnder study.

Key words: Vehicle refrigerator, Piston compressor, Oil discharge test, Muffler