Experimental and Internal Flow Investigation on the Performance of a Hydraulic Retarder with Different Liquid-Filled Amount and Blade Inclination Angles

In order to study the variation of brake torque, vibration, pressure fluctuation, exterior noise and internal flow for a hydraulic retarder with different inclination angles and liquid-filled amount, a bench-scale hydraulic retarder was built. The INV3020 data collection system was used for the synchronous acquisition of brake torque, vibration, pressure fluctuation and exterior noise signals. Experiments were performed with different inclination angles (90 degrees and 75 degrees) and six liquid-filled amount (50 vol%, 60 vol%, 70 vol%, 80 vol%, 90 vol% and 100 vol%). The torque-volume ratio was proposed to accurately analyze the influence of inclination angle on the liquid volume in stator and rotor and the brake performance. Mixture multiphase flow model was employed to capture the volume and velocity distribution. The research shows that the brake performance improves and the vibration increases with the decrease of inclination angle and the increase of liquid-filled amount. The pressure fluctuation increases as the liquid-filled amount increases, while the lower inclination angle effectively lowers the pressure fluctuation amplitude. The sound pressure level trends upward with increasing liquid-filled amount, and the lower inclination angle can effectively reduce the noise. The volume distribution of the liquid phase under different liquid-filled amount is basically consistent. The lower inclination angle can induce more vortexes.