To explore the characteristics of pressure pulsation in a twin-screw refrigeration compressor

transient pressures during the suction

compression

and discharge phases were measured

and the pressure pulsation characteristics were subsequently analyzed. The study investigated the effects of operating speed and condensing temperature on pressure pulsation and compared pressure pulsation

noise levels

and the coefficient of performance (COP) in twin-screw refrigeration compressors with slide valve control (SVC) and variable-speed control (VSC) at the same volumetric flow rate. The results indicated that pressure pulsation in a twin-screw refrigeration compressor originates from the periodic fluctuation of pressure and mass flow rate. As the rotation speed increased

pressure pulsation gradually increased from 58.6 kPa at 1 380 r/min to 141.0 kPa at 4 200 r/min. With an increase in condensing temperature from 34 ℃ to 57 ℃

pressure pulsation also increased from 132.0 kPa to 314.0 kPa. In comparison to SVC

VSC demonstrated significant advantages

featuring more than 54.6% reduction in pressure pulsation

more than 2.9 dB(A) reduction in noise

and more than 5.5% improvement in COP.