Effect of the discharge valve thickness and lift on the performance of the oil-free linear compressor in R134a refrigeration system.

As the core component of the linear compressor, the discharge valve has a significant impact on its reliability and efficiency. Therefore, studying the influence of the key parameters of discharge valve on the linear compressor is indispensable for improving the compressor efficiency and refrigeration performance. A test system based on the laboratory’s independently developed linear compressor for small refrigeration equipment was established to investigate the effects of the discharge valve thickness and lift on the volumetric efficiency, cooling capacity, and COP of the linear compressor. The transient pressure in the compression chamber was measured, and a piston stroke calculation model based on analyzing the compression chamber pressure was constructed. The dynamic characteristics of the discharge valve were analyzed using fluid-structure interaction, and its key parameters were optimized. The experimental and simulation results indicated that the volumetric efficiency and refrigeration performance with the discharge valve thickness of 0.1 mm, 0.2 mm and the discharge valve lift of 0.6 mm are the prime. This research provides valuable guidance for the optimal design of the small refrigeration linear compressor.