Through-vane compressors are used for automotive air conditioners and performance of the compressor is affected greatly by leakage loss occurring in a cylinder. The leakage loss at a vane tip is closely related to such behavior of the vane that the tip cannot maintain contact with a cylinder wall during a half-revolution of the compressor. This paper examined leakage flow through the clearance between the vane tip and the cylinder wall, and investigated its influence on the compressor performance theoretically and experimentally. It was clarified that the leakage flow increases compression torque but hardly affects volumetric efficiency of the compressor because of the specific behavior of the vane in the cylinder. Experimental results were predicted well by a theoretical analysis employing hydrodynamic lubricating theory and using the dissociation factor of refrigerant from the leaked oil.
