Modelling of an In-Line Bladder-Type Hydraulic Suppressor for Pressure Ripple Reduction in Positive Displacement Pumps

Positive displacement pumps are widely employed for their characteristics, but the pulsating flow they produce is a major and well-known drawback. To reduce the flow ripple produced by the pump, which in turn generates a pressure ripple, many methods have been investigated, from optimising the pump geometrical features to the introduction of active and passive systems to the delivery side. A passive system that has demonstrated to be particularly effective is the in-line bladder-type hydraulic pulsation suppressor. This device, consisting of a bladder gas-charged accumulator with a singular geometry, has been the subject of several studies. This paper describes a model based on the lumped parameter method for simulating and predicting the reduction effect on the pressure ripple achieved by the hydraulic suppressor. To validate the model, an experimental study was conducted, which confirmed the good potential of the model proposed thanks to the good agreement between the modelling results and empirical data.