Modeling and Simulation of Gear Pumps based on Modelica/MWorks ®

In this paper, we present a new method of modeling the hybrid external gear pumps based on Modelica and assess it experimentally. We model the whole working process of an external gear pump. The chamber of the pump is divided into a set of Control Volumes (CVs), whose effective volumes change along with the rotation of the gears. The CVs take in fluid from the inlet port and squeeze fluid out at the outlet port. The whole model of the pump also takes into account flow ripple, pressure distribution, leakages, meshing conditions, etc. Details of each component of the whole pump are provided. From the pressure distribution in space of the gear tooth, we can calculate radial force on shaft, based on which the shaft motion can be simulated. We carry out a set of predictions in MWorks and report some results on the post processing. These results are consistent with those from the experimental data.