A Novel Method for the Numerical Investigation of Pendulum Slider Pumps

Inadequate lubrication might lead to high friction and wear and can ultimately translate in a higher dissipation of energy, initiation and propagation of fracture and material fatigue. These occurrences are avoided or delayed thanks to an efficient lubricating system. The core of a reliable system is the hydraulic pump which, in the automotive field, is also responsible for power transmission and cooling. Given the importance of such components, improving reliability and performance of the pumps is a topic that is greatly pursued by manufacturers. A machine that is infrequently addressed in the open literature of the fluid power field is the pendulum slider pump. This kind of machine has the makings of high durability performance, short response time, and significant ability to withstand flow contamination by solid particles. Considering the available literature, no Computational Fluid Dynamics (CFD) studies have been presented so far. Among the complexities that hindered the application of CFD to this machine, motion complexity and narrow gaps make the development of a numerical algorithm for its modelling non-straightforward. In this work, the authors present the development and the application of a CFD model for the simulation of pendulum slider pumps. The structured mesh generation process has been successfully applied to a state-of-the-art pendulum slider pump for automotive applications, and the outcome of the numerical investigation has been validated against an on-purpose built test bench. The results both in terms of variable displacement and fixed displacement behaviour are shown. This work proofs the suitability of the developed model for the analysis of hydraulic pendulum slider pumps.