静电场和圆柱绕流耦合作用下油/水乳化液水滴变形、聚并机理研究

Study on the Mechanism of Deformation and Coalescence of Oil/Water Emulsion Droplets Under the Coupling of Electrostatic Field and Vortex

为了探究圆柱绕流形成的涡街对水滴的变形、聚结过程的影响,本文运用相场方法,建立了在圆柱绕流、静电场耦合作用的水滴变形和聚结的二维模型。在相同流速和水滴尺寸的模型中分别讨论了静电场、圆柱绕流、静电场与圆柱耦合作用等三种情况。结果表明,在边界条件相同的条件下,圆柱绕流的聚结效率比静电场的聚结效率高,且聚结后形成大水滴形状更趋近于圆形,在静电场和圆柱绕流耦合作用的情况下水滴聚并效率更高,且可以阻止高电场强度下水滴破裂。

In order to explore the influence of the vortex formed by the flow around the cylinder on the deformation and coalescence process of droplets, this paper uses the phase field method to establish a two-dimensional model of droplet deformation and coalescence under the coupling of the flow around the cylinder and electrostatic field. In the model of the same flow velocity and droplet size, three cases of electrostatic field, cylindrical turbulence, and the coupling between electrostatic field and cylinder are discussed. The results show that under the same boundary conditions, the coalescence efficiency of the cylindrical turbulence is higher than that of the electrostatic field, and the shape of the large droplets after coalescence is closer to a circle. Under the coupling effect, the droplets coalesce more efficiently, and can prevent the droplets from breaking under high electric field strength.