压电风扇激励射流强化凸表面换热研究

Utilizing a Piezoelectric Fan for Heat Transfer Enhancement on Convex Surfaces

利用数值方法,结合动网格技术,针对压电风扇激励射流强制冷却凸表面的流动换热特性进行了研究,重点分析了凸表面的相对曲率和压电风扇排布方式的影响.研究结果表明,凸表面相对曲率对流动换热效果具有显著影响,随着凸表面相对曲率的增大,壁面射流的贴壁效应越好,因此表面强化换热效果也越好.而压电风扇的排布方式主要影响换热表面的温度分布形态,顺向排布时凸表面的壁面温度围绕包络区呈哑铃状分布,而叉向分布式则呈X型分布.总之,顺向排布的压电风扇对于大曲率凸表面的强化换热作用最显著.

Using the dynamic mesh technique,a numerical investigation is performed to explore the heat transfer enhancement on convex surfaces by the vibrating piezoelectric fan.The effects of the relative curvature of the convex surfaces and configurations of the piezoelectric fan on the flow and heat transfer characteristics are investigated in detail.The results show that the relative curvature of the convex surface has a significant impact on the flow heat transfer performance.With the relative curvature,the adhesion effect of the wall jet is gradually enhanced,then the heat transfer performance of the convex surfaces is also enhanced.In addition,the configurations of the piezoelectric fan mainly affect the temperature distribution on the surface.A dumbbell-like distribution is shown when the piezoelectric fan is under longitudinal configuration.While under the transverse configuration,it presents an X-shaped distribution.In general,the piezoelectric fan under longitudinal configuration can improve the heat transfer performance of the convex surface with large curvature significantly.