封闭腔内旋转圆盘阻力扭矩特性和微沟槽减阻研究

Resistant Torque and Micro-Riblet Drag Reduction of Enclosed Rotational Disks

关键词:  离心泵  旋转圆盘  微沟槽  减阻  数值仿真

Key words:  Centrifugal pumps  Rotating disk  Micro-riblet  Drag reduction  Numerical simulation

摘要:

为了研究旋转圆盘的微沟槽减阻的作用机理，结合离心泵圆盘减阻问题，采用数值模拟的方法对封闭腔体中旋转圆盘的流场进行了仿真计算，并对微沟槽减阻的效果和作用机理进行了分析。计算结果显示，较小的法向间隙和微沟槽都能够起到减阻作用，最大减阻率为13.1%。对壁面参数和流场结构的分析表明，产生减阻效应的原因是法向间隙和微沟槽改变了局部涡的结构和位置，从而改变了湍流强度和壁面旋转剪切应力分布，导致圆盘受到的扭矩减小。研究结果展示了旋转条件下微沟槽减阻效应的作用机理，支持了微沟槽结构在离心泵等旋转机械中提高性能和降低能耗的应用。

Abstract:

Micro-riblet drag reduction has been gaining wild attention in aerospace and petroleum industry. To reveal the mechanism of the micro-riblet drag reduction on rotating disk， numerical simulations on the flow field of enclosed rotational disk are conducted. The numerical results show that smaller normal clearances and micro-riblets can reduce the resistance torque by a maximum of 13.1%. Further investigation of wall parameters and flow field structures show that the resistance torque is reduced owing to the transformation of turbulence intensity and swirl wall shear stress caused by vortexes generated by riblets. The results demonstrate the mechanism of micro-riblet drag reduction on rotational condition supporting the application on rotating machineries to enhance performances and to reduce energy loss.