Analytical determination of the vane radial loads in balanced vane pumps

The present study proposes an analytical methodology to estimate the variable loads applied to the vanes of balanced vane pumps. The dissertation is adopted to detail the nature of the different time-varying excitations that load the machine and to define their analytical calculation on the basis of vane geometry, cam ring profile and working conditions. In this context, a dimensional reduction is proposed in order to highlight how the pump geometrical parameters affect each single force component and how they may be used to modify the ratio between each load contribution. A comprehensive overview of the mutual interconnections between time-varying loads and the pump design is provided by means of a parametric study involving vane design parameters, pump displacement and cam ring shape. Admissibility of the pump geometry is verified throughout the entire study. The results show that, given the cam ring shape, the vane design significantly influences the radial loads, which may also reach negative values and promote the vane detachment.