Design and optimization of a variable displacement vane pump for high performance IC Engine lubrication Part 1 - experimental analysis of the circumferential pressure distribution with dynamic pressure sensors

In the present automotive research, increasing efforts are being directed to improve the overall organic efficiency, which, inter alia, means to improve the operational behavior of the auxiliary organs. This paper reports an experimental approach for the determination and analysis of the pressure distribution in a variable displacement vane pump for high speed internal combustion engine lubrication. More in details, an actual application is presented for a seven-blades variable displacement vane pump equipped with a hydraulic geometry variation system. This unit is characterized by a high performance, in terms of rotational speed, delivery pressure and displacement variation. The experimental layout and some relevant facilities are described. An extended test campaign was performed on the pump to characterize its operational behavior. Rotational speeds from the idling regime to the maximum sustainable regime were tested by varying the hydraulic circuit load: the results of the pressure field are shown together with a detailed description of the oil physical behavior into the pump. Furthermore, several changes in the geometry of the pump, which were suggested by the experimental campaign, are presented and their influence on the performance of the pump is evaluated and discussed with a comparative performance analysis.