矩形通道内脉动层流流场特性理论研究

摘要

本文对流量脉动条件下矩形通道内的层流流场分布特性进行了理论研究.分析了脉动周期、脉动振幅和通道结构尺寸3个因素对流场分布的影响.分析结果表明,矩形通道内脉动速度分布取决于流场中各点稳定速度分量和往复速度分量的叠加,由于往复速度的存在,使得脉动速度的分布与稳定流动存在较大不同,并对近壁区的速度梯度产生了影响.%Pulsating laminar flow field in rectangular channel was investigated analytically. The influences of the flow fluctuation period, relative amplitude and aspect ratio on the flow field in rectangular channel were analyzed. The results show that velocity is composed of the steady component and the oscillating component at every point in rectangular channel. Compared with steady flow filed, the flow filed changes a lot under pulsating condition due to the oscillating velocity component, which leads to some change of velocity gradient in the near wall region.