引潮装置流量系数的研究

Study on discharge coefficient of water admission devices in a tidal model

给排水处理构筑物的输水、配水等通常要通过孔口进行。连云港核电厂厂区前池占地范围及引水流量较大,而决定前池水位、纳潮量和淤积量的原型引潮装置孔口的尺寸又非常小,在模型中尺寸将会更小。模型的引潮装置孔口进出水流流量系数只有与原型相似,才能确保引潮装置水力特性的相似。因此,有必要进行不同比尺、不同形式及不同出流下孔口流量系数大小的试验研究。水槽试验结果表明,孔口流量系数不随水头而变化,同一孔口下的流量系数接近于某常数。进而对渐变管、拍板门和双孔口三种引潮装置的流量系数进行了研究,结果表明在同一工况下其流量系数也接近某一常数。

Orifices are frequently used in inlet/outlet devices in water supply and drainage projects.The area and discharge of the front pool at the Lianyungang Nuclear Power Station are quite large,but the orifice size of the tidal diversion works is small.Consequently,the orifice size in a scaled model would be very small.To guarantee the accuracy of diversion discharge,the similarity of discharge coefficient must be fulfilled.In this paper,an experimental study of the discharge coefficients of orifices with various shapes and flow conditions was carried out.The results showed that the discharge coefficients of an orifice under various water heads were approximately the same.The scale of discharge coefficients of orifices would meet the demand of similarity,i.e.λμ=1.Furthermore,the coefficients of discharge of transition pipes,flap gates and double orifices were also studied experimentally.The results showed that the coefficients of discharge under a specied condition were constant.