Different Flow Down The Partition Structure Sill Bottom - Flow Dissipation Force On The Floor

The high head, large flow unit width, narrow river way and riverbed erosion has become a major challenge faced by water conservancy workers, with more and more attention to environmental protection and the progress of science and technology. At this point, both ancient and mature traditional energy dissipater has been unable to satisfy the project the actual need. Traditional energy dissipater is most widely used in the underflow energy dissipation. For high-head and large single-wide flow of flood discharge project, when the stilling basin of traditional undercurrent disappearing energy in energy disappearing, it led to the near bottom velocity and fluctuating pressure of the floor are very great, with the stilling pool design standards improved. At the same time as the velocity of the bottom is too large, in order to achieve the objective of full energy dissipation, stilling pool sizes need to increase, the stilling basin project cost need to improve and so on, this a series of problems which lead to the traditional energy dissipater can not be widely used in the high water head, large discharge per unit width Engineering. Therefore, many scholars proposes a new type of dissipater conclusion according to the high water head, large discharge per unit width of the dam engineering on the base of the various advantages and disadvantages on the basis of the traditional energy industry.It is the sill of energy dissipater with step-down floor, the mechanism of the sill of energy dissipater with step-down floor is by excavating bottom vertical down to form an appropriate height, constitute a stilling basin with step-down. The existence of step-down lead to forming a water cushion before stilling basin, increasing the main jet range of the released flow energy dissipation water, it can be used to obtain greater energy dissipation rate, at the same time to reducing the indexes of near bottom hydraulic, so as to protect the bottom of Stilling basin and river bed not to be washed. Compared with the traditional stilling basin, it has the advantages of high efficiency rate, length of hydraulic jump, engineering application can significantly expand the energy dissipater, so it has very broad application prospect in water conservancy project.This paper bases on the Natural Science Fund Item Of China(51169008) 《Experimental investigation and numerical simulation about the vortex after step of the step-down bottom energy dissipater》, builds the related hydraulic model, by changing into the pool of energy, angle and fell into the pool depth of three threshold conditions, To observed, measured and recorded the stilling pool water line, pattern, dynamic water pressure, flow rate and a series of hydraulic indexes in the various proposed conditions. And through the observation and the corresponding theoretical calculation of convection mode, partition the bottom of stilling.According to the measured data to calculate the partition load of floor in the various proposed conditions. At the same time, introducing dimensional analysis, by dimensional analysis to deduce s the Semi-rational formula of the partition load. And substitution the results of the experimental data processing into semi-empirical formula., to confirms the feasibility and accuracy of semi-rational formula.