有连接管的尾水调压室稳定断面问题的理论研究

Critical Stable Sectional Area of the Downstream Surge Tank with Linking Pipe

基于Gardel关于T型三通管水头损失系数经验公式,研究分析了连接管处速度头以及进出调压室水体与尾水隧洞水体之间的动量交换对有连接管的尾水调压室稳定断面积的影响,并在托马(Thoma)理论的基础上,推导出了相应的调压室稳定断面计算公式,从而在理论上证明了连接管处的速度头对尾水调压室稳定断面所起的作用是不利的,而进出调压室水体与尾水隧洞水体之间动量交换则是有利的。研究表明:如果合理地选择设计连接管断面的尺寸和型式,就可以进一步减小有连接管的尾水调压室水位波动稳定所需的断面积。

Analyzes the effect of linking pipe velocity head and the momentum exchange between flow to and from the surge tank and that in the draft tunnel on the stable sectional area of the downstream surge tank with linking pipe by using the head loss coefficient obtained from Gardel's empirical equations for T-junction flow. Based on Thomas's theory, a formula of the stable sectional area is deduced, by which it is theoretically right to say that the velocity has a negative effect on the stability of the downstream surge tank, while that of the momentum exchange is positive. According to this study, the optimal design in the size and shape of the linking pipe helps to reduce the sectional area for stability.