两种渐扩渐缩通道内周期性充分发展层流流动的研究

本文在适体坐标系下计算了两种渐扩渐缩通道（线型通道及波纹型通道，内水的周期性充分发展流动。利用微分法和成适体坐标，选择速度逆变分量作求解变量，利用控制容积积分法得出适体坐标下的离散方程，将计算区域向两端延伸，通过两端对应位置相关量反复迭代实现周期性边界条件，算例的计算结果同理论符合良好，对于线型渐扩渐缩通道，计算结果表明，在相同的雷诺数下，随着通道倾角的增大，流动的阻力系数随着增大，当两种通道的进口高度与横截面积相同性，在相同的入口质量流量下，波纹型通道的阻力系数大于线型通道的阻力系数。

Characteristics of fully developed laminar water flow in two kinds of periodically converging-diverging channels

Flow characteristics of fully developed laminar water flow in two kinds of periodically converging diverging channels were studied in the boundary fitted coordinates. The Poisson equations were employed to generate the grid, and the contravariant velocity components were selected as the dependent variables. The control volume integration method was applied to discritize the governing equations. The periodic boundary conditions were implemented by extending the computational domain to its two ends and mutually replacing the variables in the corresponding location at the two ends. The computed results of the example exhibit good agreement with the exact solution. The calculated results show that for linear converging diverging passage, the friction coefficient increases with in creasing obliquity. It is also found that the friction coefficient of a wavy passage is larger than that of the linear one for the identical inlet height, cross section area and inlet flow rate.