Effects of groove depths on cavitation flow field in a U-shaped throttle valve
HE Jie1, LIU Xiumei1*, LI Beibei1,2, XU Huawen1
1.China University of Mining and Technology, School of Mechanical and Electrical Engineering, Xuzhou, Jiangsu 221116, China; 2.Zhejiang University, State Key Laboratory of Fluid Power and Mechatronic Systems, Hangzhou, Zhejiang 310027, China
Abstract：A CFD numerical calculation model was established in order to study the flow field inside U-shaped throttle valve. The velocity, pressure drop and cavitation region in throttle with different groove depths were also obtained. The numerical results showed that the maximum pressure is located at the upstream of the flow channel and the minimum pressure is located at the downstream of the flow channel. The pressure drops a lot and a high-speed jet forms when the fluid passes through the throttle outlet. Under the same working conditions,with the increase of groove depth, the flow in the notch increases. This situation forces the oil to flow rapidly through the orifice, which results in a change in the direction of the jet.The angle of high-speed jet shows a decreasing trend, but the maximum flow rate of oil gradually increases. At the outlet of the throttle groove, cavitation occurs near the wall of the valve cavity, and with the depth of the groove increasesing, the internal pressure of the throttle notch is recovered slowly, the cavitation area increases gradually, and the strong cavitation area in the radial section gradually expands toward the center of the throttling tank.Therefore, a reasonable control of the U-groove depth or increasing the internal resistance of the throttle can effectively inhibit the occurrence of cavitation.
贺杰, 刘秀梅*, 李贝贝,, 徐化文. 槽口深度对U型节流阀空化流场的影响[J]. 排灌机械工程学报, 2018, 36(6): 517-523.
HE Jie, LIU Xiumei*, LI Beibei,, XU Huawen. Effects of groove depths on cavitation flow field in a U-shaped throttle valve. Journal of Drainage and Irrigation Machinery Engin, 2018, 36(6): 517-523.
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