摘要
电动截止阀是流体输送的重要元件.阀的传统设计方法很少从流体角度对其流道进行设计,其流阻系数比较大,容易造成局部压力损失.流体介质通过阀口时,流动方向发生变化,可能产生诸如局部涡流、空化、水锤和死水区等水流现象及湍流脉动噪声,对阀体有很强的破坏性,降低阀的使用寿命.基于RAN-S方程组和RNG k-ε湍流模型,利用CFD技术对全开启状态下的电动截止阀的内流道进行三维的湍流数值模拟,获得其总压图、速度矢量图、湍动能强度图.通过数值模拟,可以直观地显示阀的内流道中流体的流动过程.改变进出口段流道的长度、曲率以及阀杆在流道中的布局等,进出口的压力差相对于未改进前减少30%左右,速度突变区域明显缩小,局部涡流现象消失,湍动能强度也降低了15%左右.
Electric check valve is an important component of the liquid transportation. Due to the traditional design of the valve rarely design the interal flow channel, standing in the point of the fluid flow, the flow resistance coefficient is bigger, easy to cause the certain local pressure loss.The flow direction of the fluid is changing when it passed through the mouth of the valve, and there would be the flow phenomenon, which make the valve strong destructive and reduce the service life of the valve, such as local eddy current, cavitation, water hammer and dead zones, Turbulent pulse noise, etc. The interal flow channel of the Electric check valve that is in the state of the all open is numerically simulated with CFD approach based on Reynolds-aver- aged N-S equations （RANS equations） and RNG k-v model,and the total pressure figure, velocity vector diaigram, turbulence intensity map are obtained. Through numerical simulation, the flow process of the fluid in the valve can be directly displayed.It can reduce the pressure loss of the import and export around 30%, narrow the area of the mutational speed, make the phenomenon that the local eddy current disappeared, and lessen the intensity of turbulence around 15%, by improvement designing, such as change the length and curvature of the import and export part of flow channel, and alter the layout of stem of valve, etc.
出处
《巢湖学院学报》
2011年第6期75-79,共5页
Journal of Chaohu University
关键词
电动截止阀
内流道
数值模拟
改进设计
CFD
Electric check valve
interal flow channel
numerical simulation
improvement designing
GFD
