Study of distribution mechanism for high water-based hydraulic motor

In coal mining, food manufacturing, and underwater applications, high water-based hydraulic motors (HWBHM) offer the advantages of high specific power and media friendliness. The water motors in these applications maintain the traditional structure and only replace the working medium with a high water-based fluid. However, the conventional plate flow distribution structures are limited by severe leakage, especially at low speeds and high pressure. In the context of underground emulsion drive systems for mining, a valve flow distribution mechanism comprising the valve and pentagon-wheel is proposed. Intaking and discharging processes of the motor are controlled by the valves, which are driven by the pentagon-wheel motion. A model of the motor is established using the AMESim simulation method to validate the feasibility of the new distribution structure. The numerical investigation into the flow filed characteristics inside valves shows that the valve seat with half-cone-angle of 45° improves the service life of the distribution structure. Performance experiment of a first-generation prototype revealed that pressure can be quickly built up in the plunger chamber at different conditions. Compared with traditional flow distribution mechanism, leakage of the valve flow distribution mechanism is 0.15 ml/min, which significantly improves the volumetric efficiency of the motor. The new flow distribution mechanism works well at high pressure, low speeds, and water-based medium working conditions.