直角分水口分水宽度的实验研究

Experimental Study on Diversion of Flow

本文对分水口前水流形态进行了系统的研究，测量了分水口前不同水深处的平面流场，初步给出了分水口前水流的运动形态，并据此提出各水流流态区域的划分，在对分水口前水场做概化研究的基础上，建立了分水宽度沿水深变化的估算公式。

Experimental studies for division of flow with right angels to a main channel in a shortbranch channel was carried out for various division ratios,i.e..the ratio between the dischargeof the branch channel flow and that of the main channel flow. Based on the measured data offlow velocities. eight flow regions near the intake of branch can be divided to explain the different flow configurations:(1)accelerated flow region,(2)unchanged flow region.(3)deceleratedflow region,(4)separated flow region(5)accelerated submerged flow region(6)deceleratedsubmerged flow region.(7)stagnation region.(8)recirculation region.According to the measurement.the flow of each layer may he regarded as a compound of uniform flow.orifice outflow and lateral inflow.The stream function of the compound flow hasbeen derived as follow:Φ=P1[ylnRB +(x-xB)αB]-(Pi+ps)[ylnRA+(x-xA)αA-Ps[ylnRc+(x-xc)αc]-uomy(1)The widths of diversion flow of the main channel and the branch channel along the verticaldirection were measured in order to determine the sediment load flowing into the branch channel.The following equation for evaluating the division width was established according to themeasured data:Bz/P=1.88 exp (2.12 Fr) k1.57(u/uz-0. 6k-0.75Fr-0.1).