turbine draft tube

This paper gives the flow simulation of hydraulic turbine draft tubes. Then, the calculation formula of the frequency and force of vibration of the draft tube are derived.

本文通过尾水管内流动的模拟，导出了由尾水涡带所引起的周期性振动的振动频率和脉动压力的计算公式。

The unsteady flow in a draft tube of Francis turbine under the off-design operation is produced by the dynamic behavior of a helical vortex rope with the dead core.

混流式水轮机在非设计工况点下运行时，尾水管内部的非定常流动是由死水域和螺旋涡带的动态行为引起的，尾水管上部的螺旋涡带旋转引起流动的基频脉动。

To diagnose accurately vortex rope in draft tube of hydraulic turbine, this paper presents a new method of fault diagnosis based on wavelet packet and neural network.

为精确诊断水轮机尾水管涡带，该文提出一种基于小波包特征熵的神经网络故障诊断新方法。