溢洪道弯曲泄槽水面差计算方法研究

Study on Calculation Method of Water Surface Difference of Spillway Curved Chute

按照《溢洪道设计规范》中的公式,未考虑溢洪道泄槽弯道局部水头损失计算的沿程水流流速比实际值偏大,对计算泄槽弯道段水面线横向水面差有直接影响。为找出适用于计算寒山水库弯曲溢洪道内的横向水面差的经验公式,采用模型试验验证和公式推导相结合的方法,修正了弯道陡坡泄槽沿程流速的计算公式,拟合了适用于计算该工程横向水面差的经验公式。结果表明,未考虑局部损失比考虑局部损失的沿程流速最大高出1.86 m/s,平均高出1 m/s;泄槽弯道水面差最大值出现在测点X_(3)、X_(4)之间,即弯道中心角θ_(c)为27.27°处;刘焕芳公式计算的横向水面差符合实际水面差变化趋势,并与模型试验值吻合。

According to the formula in Spillway Design Specifications,the flow velocity along the spillway without considering the local head loss is larger than the actual value,which has a direct impact on the calculation of the transverse water surface difference of the water surface line in the curved section of the spillway.In order to find out the empirical formula suitable for calculating the transverse water surface difference in the curved spillway of Hanshan Reservoir,the model test verification and formula derivation were combined to correct the formula for calculating the flow velocity along the chute with steep slope in the curved spillway,and the empirical formula suitable for calculating the transverse water surface difference in this project was fitted.The results show that the maximum flow velocity without considering local loss is 1.86 m/s higher than that with considering local loss,which is 1 m/s higher on average.The maximum water surface difference of the chute bend appears between the measuring points X_(3)and X_(4),and the central angleθ_(c)of the bend is 27.27°.The lateral water surface difference calculated by LIU HUANFANG formula conforms to the actual trend of water surface difference,and is fitted with the model test value.