圆管内三角波脉动流强化除垢性能分析

Triangle Wave Pulsating Flow for Enhanced Cleaning in Tube

对圆管层流三角波脉动压力下的流体速度分布进行理论求解,结合牛顿粘性定律得到圆管管壁处切应力的解析解。通过计算发现,三角波脉动压力下壁面剪切应力与脉动压力的振幅和频率密切相关。讨论当脉动半个周期的流量保持恒定时的壁面剪切应力变化规律,存在一个临界值频率ω^＊=265使得壁面剪切应力之比为1,当频率大于临界值时,所产生的平均切应力的值就大,强化除垢的效果更加明显。

The velocity distribution of the laminar flow inside the tube with the triangular wave pulsating pressure is solved numerically. The analytical solution of the shear stress at the pipe wall is obtained by the Newtonian law. It is found that the shear stress is closely related to the amplitude and frequency of the pulsating pressure under pulsating conditions. The variation of wall shear stress with constant flow rate for half of a cycle is discussed. There is a critical frequency that leads the ratio of the wall shear stress to 1. When the frequency is greater than the critical value, the value of the average shear stress is greater, more evident enhanced descaling effect.