Rapid predicting method for sand content of reservoir-exiting sand peak of Three Gorges reservoir in flood period

Abstract

The invention discloses a rapid predicting method for the sand content of a reservoir-exiting sand peak of the Three Gorges reservoir in the flood period. The rapid predicting method comprises the steps that firstly, a reservoir tail main stream control hydrometric station is selected as a sand peak reservoir-entering station, and a nearest main stream control hydrometric station in the downstreamposition of a dam is selected as a sand peak reservoir-exiting station; secondly, the average daily sand peak sand content S<enter> of the sand peak reservoir-entering station, the flood detention reservoir capacity V<start> corresponding to the average daily in-front-of-dam water level on the day when a sand peak appears in the sand peak reservoir-entering station, and the average daily flow Q<exit 1> of the sand peak reservoir-exiting station on the day when the sand peak appears in the sand peak reservoir-entering station are collected, and a supposed value of the average daily flow Q<sand> of the sand peak reservoir-exiting station on the sand peak reservoir-exiting day is given in advance according to the actual condition; thirdly, the sand peak reservoir-exiting ratio S<exit> / S<enter> of the reservoir is calculated according to the formula (please see the specifications for the formula); and fourthly, the sand content S<exit> of the reservoir-exiting sand peak of the reservoir is calculated according to S<exit> / S<enter> and S<enter>. According to the rapid predicting method of the sand content of the reservoir-exiting sand peak, the river way terrain, the water and sand reservoir-entering and reservoir-exiting process, the in-front-of-dam water level process and a water and sand transportation mathematical model are not needed, required information is less and easy to obtain, calculation is easy and convenient, and the accuracy is high.

Description

technical field [0001] The invention relates to the technical field of water conservancy engineering, in particular to a method for quickly predicting the sediment content of sand peaks out of the Three Gorges Reservoir during the flood season. Background technique [0002] According to the statistics of actual measurement data, after the water storage of the Three Gorges Reservoir is put into use, the time for the incoming flood peak to reach the front of the dam has been shortened from about 54 hours before the water storage to about 6 to 12 hours, while the time for the incoming sand peak to reach the front of the dam has been shortened. Then it was extended from about 2 to 3 days before water storage to about 3 to 8 days. The dissimilation of water-sediment phase makes the peak of sand passing through the reservoir lag behind the peak of flood, the hydrodynamic conditions of sand transport from the reservoir weaken, the sand peak attenuates along the way, and the sand di...

AI Technical Summary

Problems solved by technology

[0004] The technical problem mainly solved by the present invention is to provide a rapid prediction method for the sand concentration of the Three Gorges Reservoir in the flood season. Low and predictive calculations are very inconvenient

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