Study Of The High Water Head Drain Building Differential Deflecting Flow Energy Dissipation

Trajectory appears to date from extinction, developed rapidly, but in theory there are still some problems. Trajectory energy dissipation in the course of development, people are constantly improving the energy dissipation pick the shape of buckets, in order to achieve a better effect of energy dissipation. Differential has emerged, oblique style, twist, tongue-shaped and narrow, such as a series of new-style bucket picked. However, new challenges from the bucket and scour hole depth calculation formula does not update. Due to the complexity of the problem, at present new challenges away from the bucket and the calculation of the depth of scour hole also apply continuous bucket by the calculation formula for calculating them. Because different types of buckets, and guide the allocation of the flow of energy in different ways, leading to choose from and the scour hole depth varies. From the model test and prototype observation data, the application of the new bucket for bucket-type formula for the calculation of derived results and the actual deviation larger.In this paper, theoretical analysis and model test a combination of methods, for the differential extinction trajectory can do a certain depth research. Analysis of the differential trajectory of the energy dissipation of energy dissipation mechanism, and differential energy trajectory calculation of the depth of scour pool so the theory is derived. Differential in the bucket is derived from the formula out of the process, the analysis of air resistance and buoyancy of the pick away from the impact of the use of a map drawn envelope approach to drawing scour hole sphere of influence map, more intuitive to the embodiment of scour hole the impact of the building. Through the analysis and model test observations, combined with specific project examples, the following conclusions:(1) As a result of differential gear special tooth, tank construction, it's high-speed water flow and guide more fully aerated, so the air in the relatively high energy loss, resulting in scour hole depth. Formula derived in the course of using the energy method and the correction factor method to pit red calculated the energy loss, loss of energy applied to calculate the maximum depth of scour hole.(2) Application of the first amendment to further push the idea of anti-air resistance and buoyancy of the impact from the pick reflected. Bucket for the differential aeration of the water to guide the tongue, the air resistance and buoyancy influence is obvious. This paper, the formula used in copper field reservoir model test, the selected results from the calculation of 43.19m, if the application of continuous bucket pick formula derived from the results of 57.24m, while in the model test data in the measured 44m. Note the formula for calculating this paper, there must be a feasibility.(3)To map out the impact of scour hole more comprehensive plan to reflect the red of the interaction between pits. To allow more intuitive design department that will scour hole against those buildings in order to take better preventive measures.