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Nowadays the challenge in design of auxiliary devices for automotive small engines is focused on packaging reduction and on the increase of the performance. These requirements are in contrast to each other and in order to fulfil the project specifications, new and more refined design tools and procedures need to be developed. This paper presents a calculation loop developed by Pierburg Pump Technology Italy S.p.A. (PPT). It supports the design of a variable displacement oil pump component for engine applications. The work is focused on the fatigue life evaluation of a joint, which transmits the drive torque from the engine to the oil pump. The aim of the procedure is to calculate the onset of the surface fatigue phenomenon in the hexagonal joint which drives the oil pump, taking into account the axes misalignment and the flat-to-flat clearance. The study has involved several matters, experimental measures, CFD, MBA and FEM analyses.

In the modern engine of both small and large size, the acoustic emission is a very important matter increasingly studied as per specific international standards. This paper presents the study of the acoustic emission of a hydraulic rotary oil pump by means of measurement techniques and numerical approaches. This activity aims at showing a complete test-case in which both methods are used to face a noise issue and highlighting also the “weight” of the hydraulic excitation in both cases. In particular, an oil pump has been completely characterized on a test bench to verify the hydraulic performances and the noise radiation. A structural modification has been suggested with the target of altering the noise spectrum of the pump, achieving an optimization of the noise generation. From this assumption, experimental and numerical activities have started in parallel.

Aim of this work is the development of a lumped parameters simulation model of single-vane vacuum pumps for pneumatically actuated brake boosters. Kinematic and fluid-dynamic models are integrated in a simulation environment to create a tool aimed at evaluating the vacuum pump performance and at guiding the designer during the prototype development. The paper describes extensively the mathematical model, the time domain simulation and experimental analyses performed on a camshaft mounted unit. Great emphasis is placed on the evaluation of the geometric quantities of the control volumes into which the vacuum pump has been divided. For each control volume the mass and energy conservation equations lead to the determination of the instantaneous pressure. The volume of each variable chamber and the respective angular derivative are calculated as function of the shaft position starting from the stator track profile supplied as a generic closed polyline.

This paper deals with a CFD three-dimensional multiphase simulation of rotary vane pump. The paper presents a suitable methodology for the investigation of the cavitation effects and/or incondensable gases. All the 3D simulations were performed by using Fluent v12 (Beta version). A moving mesh methodology was defined to reproduce the change-in-time shape of the internal pump volumes. In particular, the pump analysis was focused on the generation, and evolution of the cavitation phenomena inside the machine to identify the locations where this phenomena could occur. Moreover, the influence of incondensable gas dissolved inside the operator fluid on both pump performance and cavitation evolution was evaluated. Significant results were obtained about the analysis of incondensable gas influence on the cavitation evolution showing that, today, CFD analysis can provide detailed information on such harmful phenomena which can not be achieved by experiments.

This study deals with the design of variable displacement oil pumps, with particular focus on wear of the inner components. A multibody model has been developed in order to achieve detailed knowledge on the dynamic loads which the main components are subjected to and to carry out a comparative analysis between different pump designs. A qualitative correlation, between the resulting wear following endurance tests and simulation results, has also been found. Design guidelines leading up to a good pump reliability have been obtained as a result of this activity.