Experimental Analysis, Modeling, and Control of Volumetric Radial-Piston Pumps

Abstract

An experimental-theoretical study has been carried out on high-pressure volumetric radial-piston pumps for diesel fuel injection systems. The dependence of the pump inducted flow rate on speed and load was investigated and the characteristic curve of the pump cooling-lubrication circuit was derived. The head-capacity curves were determined for different types of pumps at different revolution speeds and compared with the injector flow requirements in order to evaluate the pressure-control strategy efficiency. An insight into the ageing effects on the pump performance was also provided. Furthermore, the dynamic pump behavior was investigated, with specific reference to the flow-rate ripple at the delivery port. A general analytical expression has been derived for the volumetric efficiency. Furthermore, a specific procedure has been developed and applied to the experimental evaluation of the fuel leakages in pressure control valve (PCV) integrated pumps. Finally, the mechanical-hydraulic efficiency of the pump has experimentally been assessed as a function of head and speed in order to obtain a reliable evaluation of the pump shaft power and torque at different working conditions.