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Abstract Experimental and theoretical investigation was conducted to measure the friction forces between vane tip and cam-ring in oil vane pumps. The incentive of this work is to study the effect of important parameters on the coefficient of friction between vane tip and cam-ring. Such parameters are relative speed between vane tip and cam-ring, normal vane force, pressure difference between the two sides of the vane, vane tip radius of curvature, and coating of the vane tip. A comparison was performed between five different (Physical Vapor Deposition) PVD- coated vane tips and the normal vane without coating. To satisfy such requirements a special test rig was designed and constructed in the lab. A computer program was also developed to solve the Elaso-Hydrodynamic Lubriction (EHL) film. Finite deference technique was used to solve Navier Stock’s and energy equations in order to calculate the friction in the vane tip due to the shear of the lubricant. Validation of the computer model was tested using the experimental results. The results show that the effect of normal vane force and pressure difference between the two sides of the vane are very small compared to the relative speed. The coating material shows no significant effect on the friction force in oil vane pumps. Therefore the wear properties of the coating materials should be considered in future studies. For friction measurements in oil vane pumps a simple test rig design with no pressure difference between the two sides of the vane is proposed. |