Numerical Analysis of Pressure Data in a Variable-Displacement Oil Pump

A numerical analysis of pressure data carried out inside the chambers of a volumetric oil pump with variable displacement was performed. For this purpose, a dynamic model, based on the geometric and kinematic characteristics of the pump, was developed. The model allows predictions of the pressure evolution in each chamber of the pump and in the delivery piping, by employing an integrative-derivative approach. The analysis of the experimental data shows that the pressure dynamics, which is experienced by the transducers, is in some cases quite different from the pressure dynamics in the pump chambers and produces pressure peaks which are not actually present in the original signal. Thus, in addition, the pressure transducers output was modelled in order to properly compare simulation results and experimental data. Simulation results were compared with experimental data of pressure transducers, which were fitted along the periphery of the pump case and in the delivery channel.