摘要
基于FLUENT软件的动网格技术,将湍流模型与多相流技术相结合,通过计算与分析球阀阀组的结构参数对转子泵出口球阀的运动特性及球阀内部流场特性的影响规律,给出了阀球运动参数的变化曲线和球阀内部流场的分布云图。阀座半锥角小于45°时,阀球速度、升程变化较大,阀隙最大流速较小且变化较快,大于45°时,阀球速度、升程、阀隙最大流速变化较接近。阀球上下表面压差随阀座半锥角的增大而增大,且阀座半锥角大于45°时,阀球上下表面压差随介质气液比的增大明显减小。阀座入口直径增大,阀球速度、升程及阀隙最大流速变小。阀球速度随时间函数呈现先增大后减小趋势;但当介质气液比增加到0.8、0.9时,阀球速度则呈现先减小后增大趋势;随介质气液比的增大,阀球速度、升程变化梯度和阀隙开度减小,阀隙最大流速增大。气液比小于0.5时,流量系数缓慢变化,超过0.5时,流量系数发生突变,甚至于在超过0.65以后,流量系数急剧变化超过1.0。
Basing on dynamic mesh model offered by FLUENT, influence laws have been conducted that structural parameters of ball valve group on the motion characteristics of export ball valve and the flow field characteristics of the valve gap. Movement parameters curve of valve ball and flow field distribution are obtained. When the seat half cone angle is less than 45°, the changes of speed and lift are bigger, maximum flow rate of the valve gap is smaller and faster. More than 45°, the valve ball speed, lift and maximum flow rate of the valve gap closer. Differential pressure of valve ball surfaces increases with the seat half cone angle increasing, and while the seat half cone angle is greater than 45°, differential pressure obviously reduces with gas-liquid ratio increasing. The larger the diameter of the valve seat inlet, the smaller speed lift of valve ball and the maximum flow rate of the valve gap. Over time, speed of valve ball increases then decreases, it is contrary when gas-liquid ratio is 0.8, 0.9. Speed, lift and the opening of the valve gap decreases, maximal velocity of the valve gap increases along with the increasing of gas-liquid ratio. Gas-liquid ratio is less than 0.5, the flow coefficient slowly changes. Once it is more than 0.5, the flow coefficient will mutates, even after more than 0.65, the flow coefficient over 1.0.
出处
《液压气动与密封》
2014年第7期6-9,共4页
Hydraulics Pneumatics & Seals
关键词
球阀
动网格
结构参数
数值分析
ball valve
dynamic mesh
structural parameters
numerical analysis
