CFD Modelling of an Internal Gear Pump for High Viscosity Fluids

The paper presents the CFD modelling of an internal gear positive displacement pump used for pumping high viscosity fluids. The aim of the study is to show the proper methodology for the evaluation of the delivered flow rate in conditions of incomplete filling. The model was developed in SimericsMP+ with the general gear template. It features axial and radial feeding of the variable chambers and all leakage passageways. The model was calibrated in terms of leakage flow rate in conditions of complete filling, then validated on the steady-state flow rate as a function of the suction pressure. Good agreement was found in the evaluation of the critical operating condition for which the incomplete filling begins. Based on the obtained results, it has been demonstrated that the simulation methodology can be used with a good degree of confidence for predicting the pump behavior. Hence, the model seems suitable for designing and optimizing such kinds of machines.