Capacity control of refrigeration screw compressor

UDC 621.514

Capacity control of refrigeration screw compressor

Noskov A.N., Zimkov A.A., Tarasenkov D.S.

Different ways of refrigerant screw compressor capacity control are analyzed. Low effectiveness of modern ways of control is shown. Estimation criteria for screw profiles geometry are proposed: reduced relative length of screw contact line and reduced relative area of discharge port. Comparison of screw profiles with different geometry and different numbers of teeth is made. Perspective method of capacity control and geometrical compression ratio by valve and swinging dampers is discussed. Comparison of work loss for refrigerant screw compressor with different numbers of teeth with the ones with different screw profiles during discharge process is made. Compressors are operated at R22 and R717 refrigerants, the capacity control being made by one valve and valve with swinging dampers. Research of refrigerant screw compressor with potential regulator allows determining the law of geometrical compression ratio variation as compressor capacity is being decreased, when the indicated efficiency is increased up to 40 % compared to the compressor with capacity adjuster in the form of one valve.

Keywords: refrigerant screw compressor, capacity control, compressor work loss, laws of control

Read the full article