具有正弦粗糙度的环形微管道中脉冲流动

Oscillating Flow in Annular Microchannels With Sinusoidally Corrugated Walls

研究了具有正弦粗糙度的环形微管道中脉冲流动,其中壁面粗糙度用小振幅的正弦波表示,不可压缩粘性脉冲流动由周期振荡的压力梯度驱动,运用摄动展开法求解了柱坐标系下的动量方程,获得了环形微管道内脉冲流动的近似解析速度及其体积流率.在此基础上,研究了相关无量纲参数,如Reynolds(雷诺)数Re、压力梯度振幅A、正弦波状粗糙的小振幅ε、内外半径之比α、相位差β及其波数λ对速度u及平均体积流率Φ_m的影响.结果表明,剖面速度随A的增大而增大,随Re的增大而减小,相位滞后χ随振荡Reynolds数Re的增大而增大.

Oscillating flow in annular microchannels with sinusoidal wall roughness was investigated. The oscillating flow of incompressible viscous fluid was driven by a time-periodically oscillating pressure gradient. Approximate solutions of the velocity and flow rate in the annular microchannel were obtained through computation of the momentum conservation equations in the cylindrical coordinate system with the perturbation method. lutions, the effects of the relevant nondimensional parameters, Based on these approximate sosuch as Reynolds number Re, pressure gradient amplitude A, sinusoidal roughness amplitude ε, ratio of the inner radius to the outer radius α, phase differenceβ and wave number λ, on velocity u and flow rate φm, were analyzed. The results show that the velocity increases with A and decreases with Re, and phase lagχ increases with Re. Key words： pressure gradient oscillation; perturbation method; sinusoidally corrugated wall; annular microchannel