Thermal-hydraulic performance prediction in fluid power systems

This paper presents a modelling approach to the study of thermal-hydraulic performance in fluid power systems. A set of lumped parameter mathematical models are developed which are based on conservation of mass and energy for the system. The theoretical basis and modelling strategy are discussed for an open circuit containing a hydraulic pump, loading valve, heat exchanger and reservoir. Simulation results are presented which show a comparison of model/rig performance, and the agreement obtained demonstrates the validity of the modelling approach. It is shown that the thermal response is dominated by the reservoir heat capacity and that close correspondence between the model and rig is only achievable with accurate hydraulic performance models.