Theoretical and Experimental Investigation on Comparing the Efficiency of a Single-Piston Valved Linear Compressor and a Symmetrical Dual-Piston Valved Linear Compressor

The efficiency of the valved linear compressor is very important to the efficiency of the space J-T throttling refrigerator. To compare the efficiency of the single-piston valved linear compressor (SVLC) and the symmetrical dual-piston valved linear compressor (SDVLC), this paper explores the factors that affect efficiency. Firstly, this paper analyzes the mechanical vibration system of the linear compressor, the result shows that the efficiency is highest when the external force (current) is in phase with the speed. Then the numerical solutions of the current and velocity are obtained. By comparing the variance and same direction rate of the current and velocity between the SVLC and SDVLC, the reason for the difference in efficiency is explained. Subsequently, the performance of the SVLC and SDVLC are tested on the experimental system. The result shows that the current and velocity of the SDVLC are more in phase, and the isentropic efficiency, volume efficiency and motor efficiency of the SDVLC are all higher than that of the SVLC.