3D CFD numerical analysis of vane dynamic effects on the pressure ripple in a variable displacement vane pump

A numerical three-dimensional CFD analysis of a variable displacement vane pump has been conducted, investigating the effects on the pressure ripple caused by the vane detaching from the pressure ring. The volume of the fluid over the vane tip has been re-meshed at every time step as a function of the forces acting on the bottom and the top of each vane. The numerical model has been developed using the commercial tool, Simerics MP+, including turbulence and cavitation models. The validation of the model has been done comparing numerical and experimental data. It has been observed that the detachment of the vane occurs during the transition zones when unwanted pressure spikes are generated by a nonoptimized valve plate design. The prediction of vane detachment is crucial for designing a quieter and more durable pump. Vane collision on the stator ring can be a source of noise producing premature wear of both components. Vane detachment from the stator ring has a large effect on pressure ripple even if the volumetric efficiency is only slightly influenced.

An Empirically Derived Pressure Compensation Control System for a Variable Displacement Vane Pump

Pressure compensated vane pumps are well suited to applications such as automatic transmissions which require a low-cost, compact solution to provide the hydraulic power required for clutch control as well as the lubrication and cooling functions. This paper presents a black-box model of the series of valves providing the flowrate to control the motion of the pivoting cam in a variable displacement vane pump from an automatic transmission application. This series of valves consists of a pressure-reducing valve followed by a solenoid-operated valve that generates a pilot pressure acting on the main pressure regulator valve to adjust the commanded pump outlet pressure setting. Valves taken from a transmission control block were integrated into a custom unit and installed on a test rig with a modified vane pump. Measurements previously collected on this test rig were used to validate a lumped-parameter vane pump model and provide data containing the input-output relationships of the pressure compensation system valves. An analysis of the black-box description of this control system identifies limitations to the achievable system performance. This analysis reveals that the low-cost solenoid-operated valve and the arrangement of the valves within the control circuit both contribute to a controllable bandwidth less than 2Hz. Finally, the paper presents an alternate control system design capable of improved system performance.

Comprehensive Simulation Model of a High Pressure Variable Displacement Vane Pump for Industrial Applications

This paper deals with the hydraulic model of a high pressure variable displacement vane pump for industrial applications. The simulation is based on a 0D model implemented in the Amesim® environment with customized libraries. The geometry of the pump is described analytically or numerically and different leakage passageways are taken into account. The evaluation of some critical parameters was performed by means of 3D simulations. A finite element analysis allowed determining the deformation of the port plate for correcting the current axial clearances. A CFD analysis was performed for the evaluation of the discharge coefficients in the valves of the displacement control. The model was validated experimentally in terms of steady-state flow-pressure characteristics and of displacement control dynamics.

Lumped Parameter and Three-Dimensional Computational Fluid Dynamics Simulation of a Variable Displacement Vane Pump for Engine Lubrication

The paper describes the modeling and the experimental tests of a variable displacement vane pump for engine lubrication. The approach used for the simulation has involved three-dimensional (3D) commercial tools for tuning a zero-dimensional (0D) customized model implemented in the LMS Amesim® environment. Different leakage paths are considered and the axial clearances are variable to take into account the deformation of the pump cover, calculated through a finite element analysis with ANSYS. The vane tip clearances are calculated as function of the dynamic equilibrium equation of the vanes. The displacement control takes into account the internal forces on the stator due to the pressure in all variable chambers and to the contact force exerted by the vanes. The discharge coefficients in the resistive components have been tuned by means of a complete 3D transient model of the pump built with PumpLinx®. The tuned 0D model has been proved to be reliable for the determination of the steady-state flow-speed and flow-pressure curves, with a correct estimation of the internal leakages and of the pressure imposed by the displacement control. The pump has been also tested using a simplified circuit, and a fair agreement has been found in the evaluation of the delivery pressure ripple.

Lumped Parameter and Three-Dimensional CFD Simulation of a Variable Displacement Vane Pump for Engine Lubrication

The paper describes the modelling and the experimental tests of a variable displacement vane pump for engine lubrication. The approach used for the simulation has involved 3D commercial tools for tuning a 0D customized model implemented in the LMS Amesim® environment. Different leakage paths are considered and the axial clearances are variable to take into account the deformation of the pump cover, calculated through a finite element analysis with ANSYS®. The vane tip clearances are calculated as function of the dynamic equilibrium equation of the vanes. The displacement control takes into account the internal forces on the stator due to the pressure in all variable chambers and to the contact force exerted by the vanes. The discharge coefficients in the resistive components have been tuned by means of a complete 3D transient model of the pump built with PumpLinx®. The tuned 0D model has been proved to be reliable for the determination of the steady-state flow-speed and flow-pressure curves, with a correct estimation of the internal leakages and of the pressure imposed by the displacement control. The pump has been also tested using a simplified circuit and a fair agreement has been found in the evaluation of the delivery pressure ripple.