宽戗堤截流龙口水力特性研究

摘要

通过模型试验对宽戗堤截流龙口范围内的水流特性进行系统研究.试验结果表明:当宽戗堤宽度与总水头的比值B/H0在3.1～5.7之间时,随着戗堤宽度的增加,戗堤表现出宽度效应,龙口内水面形态由单降型流态变为双降型流态,龙口中下部流速降低明显,龙口前壅水高度逐渐增大;当B/H0＞5.7时,戗堤的宽度效应减弱;当B/H0＜3.1时,龙口区域没有宽度效应.运用多元回归分析,初步研究了各因素对宽度效应的影响.%The characteristics of water flows through the closure gap of wide dikes were studied based on model tests.The model tests show that when the ratio of the dike width to the total head is 3.1 ～ 5.7, with the increase of the closure width, the wide dike exhibits width effects, and the water surface shape in the closure gap has changed from single-drop flows to double-drop ones.The flow velocity in the middle and lower part of the closure gap obviously decreases, and the water level in front of the closure gap increases.When the ratio of the dike width to the total head is larger than 5.7, the width effects of the wide dike decreases, and when it is smaller than 3.1, there is no width effects in the closure gap.By means of the multiple regression analysis, the influences of various factors on the width effects were preliminarily studied.