曲面溢流悬板倾角对排沙漏斗流场特性的影响

Influence of Inclination Angle of Curved Overflow Deflector Taper on Flow Field Characteristics of Vortex Setting Chamber

排沙漏斗的流场特性对其水沙分离性能具有决定性作用,为了探究曲面悬板的倾角对排沙漏斗流场特性的影响,利用大涡模拟和VOF相结合的方法,对曲面悬板倾角分别为5°、10°、15°时的排沙漏斗三维流场特性开展研究,并与相同进流量下排沙漏斗设置平面悬板时的流场特性进行对比。结果表明,采用曲面悬板可增大漏斗室内的涡流强度,减小低流速带的范围,倾角增加能提高空气涡的稳定性、增加空气涡的强度和尺寸,有利于水沙旋流分离;锥体区径向流速随倾角增加而增大,且基本指向漏斗中心,有利于泥沙快速输移至排沙底孔;曲面悬板表面溢出水流的流速大于平面悬板表面的流速,且倾角θ为15°时,悬板上流速最大。

The flow field characteristics of vortex setting chamber(VSC) play a decisive role in its water and sediment separation performance.In order to clarify the influence of the inclination angle of the curved deflector on the flow field characteristics of VSC,the large eddy simulation and VOF method are used to study the three-dimensional flow field characteristics of the VSC when the inclination angles of the curved deflector are 5°,10° and 15° respectively,and the flow field characteristics of the VSC with the plane deflector under the same inlet flow rate are compared.The results show that the use of curved cantilever deflector will increase the eddy current intensity in the VSC chamber and reduce the range of low velocity zone.The increase of the inclination angle can improve the stability of the air vortex,increase the strength and size of the air vortex,which is beneficial to the separation of water and sediment.The radial velocity in the cone area increases with the increase of the inclination angle,and basically points to the center of the VSC,which is conducive to the rapid transport of sediment to the bottom hole of the sediment discharge.The velocity of the overflow flow on the surface of the curved deflector is greater than that on the surface of the plane deflector,and the flow velocity on the deflector is the largest when the inclination angle is 15°.