Abstract
A study on using numerical analysis and experimental test to predict where cavitation will occur in a hydraulic gear motor was carried out in order to present the viability of using numerical analysis tools for cavitation prediction. The branch of numerical analysis best suited for the study was computational fluid dynamics (CFD). In particular, the approach of multiphase mixture modeling was used due to the dual phase existence of the working fluid characterized by cavitation. For numerical analysis validity, a physical experiment was performed using knowledge of cavitation inducing techniques involving differential pressure between the inlet and outlet ports of the motor. This was acted upon a Sauer-Danfoss D-Series hydraulic motor of typical use on heavy equipment machinery. A set of 5000 psi rated needle valves placed near the inlet and outlet ports of the motor were used to induce a vacuum at the suction port in order to induce cavitation and for the latter, provide the necessary backpressure required of the system. Cavitation was induced to the point of physical damage to internal gear motor components. The location of the damage was noted and compared to numerical analysis multiphase simulation results. Comparison of experimental and theoretical results yielded the viability of using numerical analysis for cavitation prediction in a hydraulic gear motor.