Study on Cavitation Effect of Hydraulic Retarder 2022-01-1169

Hydraulic retarder is important auxiliary brake device which widely used in commercial vehicles for its economy, safety and driving comfort, however cavitation will occur and reduce the braking performance when hydraulic retarder operates at high speed. In this paper, a model of hydraulic retarder considering cavitation effect was established, and the reliability of the model was verified by comparing with the external characteristics of the product which was obtained from Voith’s official discloses data. Then the cavitation of hydraulic retarder under high-speed working condition was studied by the establishing simulation model. The simulation model can describe and analyze the internal flow field in the hydraulic retarder, and can be used as an important tool for the development and optimization of hydraulic retarder in the future. When hydraulic retarder’s rotational speed is about 1500rpm, the cavitation will be observed in the working chamber. When the outlet flow rate is low and the oil filling rate is high, the oil vapor fraction is greater than the air fraction. With the increase of the outlet flow rate, the oil fraction decreases, the oil vapor fraction first increases and then decreases, and the air fraction increases gradually and dominates after a certain out flow rate is exceeded. Air coming in from the float-bowl vent can suppress the cavitation inside the hydraulic retarder.