Effect of Temperature and Pressure on the Leakage Flow Characteristics of the Bent Axis Hydro-Motors-An Experimental Study

摘要

This article investigates the steady-state leakage flow (hydraulic oil) characteristics of the bent axis hydro-motor fitted in an in-house fabricated hydrostatic transmission (HST) system. In this respect, two different classifications of the bent axis hydro-motors, fixed displacement and variable displacement types, are taken into consideration, which is generally used in heavy earth moving vehicles. The leakage flow paths in these two selected hydro-motors are studied considering their constructional detail. A mathematical model is established to estimate the leakage flow of the said hydro-motors that accounts the change in viscosity with respect to the operating state variable, i.e., absolute temperature and operating pressure, where the coefficient model is obtained from the test data. Using the established model, the leakage flow characteristics of the hydro-motors are obtained at different operating conditions and are verified experimentally. From the study, it is concluded that with the increase in load pressure and temperature of the working system, the leakage flow of the hydro-motors used in the heavy earth moving vehicles also increases.