Through the testing research of hydraulics model, this paper educes the depth of the cavity back water,bottom slope down stream,ridge height,the speed on the ridge,water depth,unit width flux,Froude Number which has relation with water lingua striking angle down stream and the qualitative analysis for influencing the back water.
The Dachaoshan hydropower project has adopted the flaring pier stepped dam face and bucket combined energy dissipator in its design, and the prototype observation of overflowing hydraulics under the design water level was carried out in June, 2002. The streamwise pressure, bottom flow velocity and aeration over the 4 steps along the stepped dam face were measured, and the data on operations under a dam height of over 100m and a per unit width discharge of 165m3/s were obtained.
These observation results have provided very important scientific basis for wide application of the flaring pier stepped dam face under the design condition of a high dam and a large per unit width discharge.
The prototype observation results have been obtained on the basis of the systematic test and research as well as of application of the design study results in the design and construction of the dam, taking into account the design optimization and construction of the Dachaoshan hydropower project in the study, and thus a new successful living example of constructing a RCC dam with a height of over 100m and a large per unit width discharge has been provided.
Characteristics of film hole irrigation and effects of irrigation technological parameters on irrigating quota are analyzed, and the relationships among discharge per unit width, hole spacing and irrigation quota are studied in this paper, based on field experimental data.
According to many model experiments, the paper analyzed the relations between scour depth in turbid-water and discharge per unit width、sediment concentration、sand fraction and the impact of tailwater depth and sediment discharge on scour pit depth in details, discussed the variation relationships between the ratio of turbid-water to clear-water and Froude numbers, selected a suitable formula of turbid jet-trajectory distance.
The discharge per unit width, head and velocity are big and natural condition at downstream energy dissipation area is poor. Problems of fluid state control of high-velocity flow and energy dissipation are prominent.
To design a low-head control division project, the question deciding parameters will be met, such as: free flushing water levels, discharge per unit width of gates, net width of gates, elevation of gate sill, relative differences of heights of gates.
The question that how to solve the problem of the energy dissipation and erosion control effectively in the condition of the low head and low Fr. hydraulic jump and high single breadth discharge is a common diffcult problem of diversion works in low head.
In this article, a new type energy dissipater, T-shape pier is lied on cement-rubble apron, which is used in energy dissipation and erosion of low head and low Fr. hydraulic jump and high single breadth discharge, is bring up.