The paper presents an extensive analysis of the influence on the suction capacity of the main geometric parameters of gerotor lubricating pumps. The study was carried out using a computational fluid dynamics (CFD) model developed with the commercial software PumpLinx®. The model of a reference gerotor unit was validated experimentally in terms of delivered flow rate in different operating conditions, in open and closed circuit configuration. In the former case, different geometries of the inlet pipe were tested. In the latter, the influence of the suction pressure at constant speed was analyzed. After the model validation, several geometric features were changed to assess their influence on the volumetric efficiency in conditions of incomplete filling, such as the thickness and the diameter of the gears, the position of the inlet pipe with respect to the rotors (radial, axial, and tangential), and the shape of the port plate.
The paper presents an extensive analysis of the influence on the suction capacity of the main geometric parameters of gerotor lubricating pumps. The study was carried out using a CFD model developed with the commercial software PumpLinx®. The model of a reference gerotor unit was validated experimentally in terms of delivered flow rate in different operating conditions, in open and closed circuit configuration. In the former case different geometries of the inlet pipe were tested. In the latter the influence of the suction pressure at constant speed was analysed. After the model validation, several geometric features were changed to assess their influence on the volumetric efficiency in conditions of incomplete filling, such as the thickness and the diameter of the gears, the position of the inlet pipe with respect to the rotors (radial, axial and tangential), the shape of the port plate.
In positive displacement pumps, the main volumetric loss at high speed is due to the incomplete filling of the variable volume chambers. The prediction of the limit speed and of the maximum flow rate delivered by a pump can be obtained only through Computational Fluid Dynamics (CFD) simulations, since the shape, the orientation, and the movement of the chambers with respect to the inlet volume must be considered, along with the non-uniform distribution of the gaseous phase, due to the dissolved air release. In this paper, the influence of different geometric parameters on the filling of a vane pump has been investigated through the commercial software PumpLinx®. At first, a model of a reference pump has been created and validated with different configurations of the suction flow area, then a simplified model has been used for assessing the influence of the geometry of the rotating assembly. It was found that a pump with a low ratio between the axial thickness and the diameter has a higher volumetric efficiency if the chambers are fed from one side only. Opposite behaviors were found in the case of pumps with small diameters and high thicknesses. Moreover, the filling could be improved by increasing the number of chambers, and by reducing the diameter of the rotor, even only locally.
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.
The paper describes a multi-domain simulation of a gerotor oil pump. Three different analysis tools have been used in synergy to predict the pump flow rate, in both conditions of complete and incomplete filling, and the pressure ripple. The computational fluid dynamics software PumpLinx® has been used for the determination of the discharge coefficients, while a finite element model analysis performed with ANSYS® has allowed the evaluation of the deflection of the pump cover under the action of the delivery pressure. The data calculated with the 3D tools have been utilized as input for a lumped parameter model of the pump developed in LMS Amesim® with customized libraries. The aim of the study is to supply the guidelines for tuning the models using a reduced number of computational fluid dynamics simulations. The results collected in the experimental campaign have demonstrated that a lumped parameter approach can be suitable, if properly calibrated, to predict the pressure oscillations in conditions of defective filling. Moreover, it was found that the cover deflection has a significant importance not only on the leakages, but also on the pressure ripple.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.