Inversion Study On The Shoal Types Of Hydraulic Parameter Of Rapids Abating

There are many waterway with rapids in mountainous rivers in western China. Study on the hydraulic parameter of rapids abating is the important content of navigation project.At present,many studies have been conducted for the waterway regulation rapids,but lack of a series of studies on the hydraulic parameter of rapids abating. While velocity and gradient are known,there are less study on how to find some methods of the mathematical model and river mode test,through inverse some of the terrain conditions,achieve hydraulic parameter of rapids abating for the river model and ship model test. This paper inversion study on the hydraulic parameter of rapids abating through mathematical model and experiment,and obtain some conclusion as follow:1.After hydraulics formula derivation , established the relationship between roughness and water depth which meet the requirement of the hydraulic parameter of rapids abating,can seek a certain degree of depth on a certain roughness conditions,so that velocity and gradient meet the requirement of navigation hydraulic index. And make the relationship between velocity and gradient graphical, through the engineering example calculations show that by the test conditions,when there is a small velocity with a large gradient,flume experiment has been difficult to achieve the combination by adding rough,adjusting the flow quantity water depth and other methods.2.Exaboratethe reason, test equipment, model design programs of the front bottle-neck model of flume experiment. Through comparative analysis of the results of figure and hydraulic parameter of rapids abating,that flume experiment achieve some combination of the hydraulic parameter of rapids abating.But flume experiment is difficult to achieve stable velocity-gradient for a long reach.3. The two-dimensional flow model is applied to practical engineering,validate the water level and velocity, the two-dimensional flow model is proved correct and rationality, then it can be used in the beach-tpye inversion mathematical model in this paper. Contrast annlysis on the flume experiment and mathematic model calculation results, further verified the rationality of the flume experiment results.4. Establish mathematical model, calculate the programs of broad-crested weir and front or back bottle-neck model. Through comparative analysis of the mathematical model calculate results and hydraulic parameter of rapids abating,obtained on behalf of the terrain conditions,can achieve some combination of the hydraulic parameter of rapids abating.