OPTIMIZATION OF RELEVANT DESIGN PARAMETERS OF EXTERNAL GEAR PUMPS

Abstract

This paper describes a numerical procedure for the analysis and the optimization of external gear pumps. The Fluid Power group of the University of Parma has implemented a numerical code for the simulation of external gear pumps and motors; the code is named HYGESim and it is based on a lumped parameter approach implemented in AMESim, writing proper submodels in C language. This work is focused on the optimization of the pump design with particular reference to the geometry of the recesses machined on the bushings. The procedure is based on a path search method known as Steepest Descent and optimizes the considered parameters starting from a design taken as initial reference. The objective functions defined for the optimization permit to account for the volumetric efficiency, the delivery pressure ripple, the maximum and minimum pressure peaks during the meshing process. An optimal design of the recesses has been proposed and a prototype of a pump, equipped with the proposed geometry of bearing blocks, was tested. Measured data and the comparisons with the experimental results obtained for the stock pump taken as reference are presented in the paper, confirming the potentials of the developed optimization methodology.