煤矿水压安全阀异形阀腔瞬态空化特性研究

Study of Transient Cavitation Characteristics of Shaped Valve Cavities in Coal Mine Hydraulic Safety Valves

安全阀是煤矿液压支架水压化的关键元件,但由于水介质的汽化压力较高,导致液压元件在节流口处易产生空化。为了深入研究煤矿水压安全阀异形阀腔瞬态空化流场分布,通过Fluent软件,对简化后的安全阀异形阀腔流场分别进行网格和时间步长独立性验证,确定了网格数量与时间步长后对异形阀腔流场进行瞬态分析。通过瞬态模拟仿真结果可知:流场内部存在着一定的周期性空化流动,湍动能条带的前、后端处促进了空化云团的产生、发展和溃灭,空化周期的变化规律和湍动能值的变化趋势相反。速度漩涡和由高速射流区产生的湍动能条带是影响周期性变化的重要因素。

The safety valve is a key component of hydraulic support hydraulic pressurization in coal mines,but the high vaporization pressure of the aqueous medium causes the hydraulic components to be prone to cavitation at the throttle port.In order to study in depth the transient cavitation flow field distribution in the shaped cavity of the coal mine hydraulic safety valve,the simplified shaped cavity flow field of the safety valve was verified separately by Fluent software for grid and time step independence,after determining the number of grids and time steps,transient analysis of the shaped cavity flow field was carried out.The results of the transient simulation show that there is a certain periodic cavitation flow inside the flow field,the front and rear ends of the turbulent kinetic energy band promote the generation,development,and collapse of cavitation clouds,and the variation trend of cavitation period is opposite to that of turbulent kinetic energy value.The velocity vortex and the turbulent kinetic energy strips generated by the high-speed jet area are important factors affecting the periodic variation.