NUMERICAL CALCULATION OF PNEUMATIC LOSSES IN A ROTARY VANE COMPRESSOR

Abstract

Positive displacement pneumatic compressors rely on suitable sealing in order to achieve the required pressure and work efficiently. Most rotary vane compressors rely on a thin film of hydraulic oil that forms between the vanes, stator, rotor, and the end plates. The oil film has the role of sealing to minimize air losses, but also to reduce the wear between the components. If the clearance between the different components is too large a significant amount of air escapes and the compressor does not achieve sufficient outlet pressure. If it is too small, machining costs increase and it is also possible for the vanes to get locked and damage the compressor. The paper calculates the amount of air lost through internal leakage in a vane compressor based on the clearances between the components. An algorithm that uses the equation for the flow of a fluid through a straight tube of constant cross-sectional area is proposed and proprietary software is developed for a numerical transient simulation.