THEORETICAL AND EXPERIMENTAL STUDIES OF THE STEADY-STATE PERFORMANCE OF AN ORBITAL ROTOR LOW-SPEED HIGH-TORQUE HYDRAULIC MOTOR

In this paper the steady state performance of epitrochoid generated or bital 'rotary piston machine' (ROPIMA) type 'low-speed high-torque' (L SHT) hydrostatic unit has been studied. The complex variation of the v olume of a chamber of such a machine with shaft rotation, along with t he various flow and torque losses, demand a structured approach to arr ive at its mathematical model. In conventional approaches the system m orphology becomes obscured as the mathematical model is approached. Bo ndgraph provides a structured approach to model engineering systems in a simplified manner. A reduced Bondgraph model of the LSHT Orbital mo tor is made where the various losses are lumped in suitable resistive elements. The variations of the loss coefficients are identified. The predicted performance of the motor has been experimentally verified.