Study On Hydraulic Characteristics Of The Vertical Slot Fishay With Pool Structure Changes

Vertical slot fishway is one of the main layout types of fishway at present.Many experts and scholars at home and abroad have carried out a lot of experimental research on its hydraulic characteristics,However,the effect of different types of diaphragm pier head on fishway pool chamber is less,In this paper,based on the existing research,three different types of vertical slot fishway diaphragm pier head are designed:smooth pier head,hook type pier head and semicircular pier head.The flow characteristics of conventional tank,such as discharge,water surface profile,flow pattern distribution,turbulent kinetic energy and vertical joint cross-section velocity,are studied by combining physical test and numerical simulation,The main research contents and conclusion are as follows:(1)Through the measurement and analysis of the overflow flow of different types of diaphragm pier head,it is found that the overflow flow range of smooth diaphragm pier head and hook type diaphragm pier head is basically consistent,while that of semi-circular diaphragm pier head is relatively large(2)The results show that the water surface profiles of the three types of diaphragm pier head are consistent with the bottom slope;the head drop of each tank is basically similar to the design value,the error of smooth type and hook type diaphragm head is less than 10%,and that of semi-circular diaphragm pier head is about 26%.(3)Under the same water depth,the vertical joint velocity of smooth type and hook type diaphragm pier head is similar,and the velocity at the vertical joint of semi-circular diaphragm pier head is larger,and the maximum velocity value is 1.45m/s.(4)Through the analysis of flow pattern and main flow velocity,it can be seen that the shape of diaphragm pier head is different,the area of backflow area on both sides of main flow area is different,and the velocity characteristics and attenuation rate along the main flow area are different,which are shown as follows:the main flow curvature of smooth diaphragm pier head is the largest,that of semi-circular diaphragm pier head is the largest,and that of hook type pier is the largest The area has the highest decay rate.The results show that the change of diaphragm pier head has little effect on the turbulent kinetic energy,and the turbulent kinetic energy values of three different baffle pier head types are similar.(5)Based on the principle of "the mainstream does not adhere to the wall",the design scheme of improving the flow pattern in the rest pool is proposed.Figure[50]table[8]reference[78]...