Numerical Analysis Of The Dynamic Behaviour Of Piston Journal Bearing In Axial Piston Pumps And Motors

This work presents a numerical analysis of the piston dynamic behaviour in axial piston swash plate type pumps and motors. The numerical method adopted is based on the solution of the piston motion equations which depend on the pressure distribution within the cylinder-piston gap. In order to determine this contribution, the Reynolds equation is applied in the lubricating fluid film between the piston and the cylinder. Besides the piston dynamic behaviour, the model permits to calculate the leakage flow through the gap and the friction forces acting on the piston and cylinder surface.After the presentation of the numerical procedure, the dynamic behaviour of the piston is firstly discussed, highlightingthe stability of the bearing. This work is part of a wider research activity focused on the study of positive displacement machines, with the aim to determine and maximize their global efficiency.