| Side wall long corridor water conveyance system is a kind of simple decentralizedwater conveyance system which is suitable for the low-head navigation locks. It has asimple design, a low foundation excavation depth and low cost. What is more, theberthing conditions of the lock chamber are better compared to the centralized waterconveyance system.it can not set up sedation segment. And it is widely used in theTennessee River Valley development. In China, it is seldom used due to the initial waterdepth is less and the scale of the ship in the old navigation locks is smaller which have abig impact on the berthing conditions. With the rapid development of our country, thelocks of the scale of construction and ship scale has changed greatly, which create theconditions for the application of side wall long corridor water conveyance system.Due to the influence of the water inertia which is not considered, in the beginningof irrigation and sluice, the locks will produce a surface slope. And at the same timebecause of the flow strength, the flow energy is more concentrated, which cause the shipto be subject to greater lateral force and is not conducive to safe anchorage. So at homeand abroad, a lot of experts do much research about the water branch hole flow type,the layout of the export of energy dissipater,the effect of energy dissipation and so on inrecent years. But by means of research, this technology specifically to the model testand numerical simulation of less is even more rare in our country for the threshold depthis relatively small locks.This paper proposed by the way a simulation study on the side wall long corridorwater conveyance system, focusing on exploring the different water hole section layoutpattern, the water hole aperture, the spacing of the energy dissipation threshold, thethreshold higher, the flow of energy dissipation and dispersion. And then analyze theenergy dissipation mechanism, and find its own rules. At the same time, for the type ofdistribution system to promote the use of lay the foundation.In this paper, rectangular support hole sectional form of the circular support holesection with the previous studies the hole flow effect, obtained a circular branch holesection effluent hole over the flow, the drag coefficient is small, the water hole than therectangular branch pipe section better than the outflow. This article and through thephysical model and a three-dimensional mathematical model combining in-depthanalysis of the water the arrangement position of the branch hole section size and energy dissipation threshold can be concluded that: the cross-sectional area of the waterhole orifice size, energy dissipation threshold arrangements location of the gate indoorwater flow patterns affected significantly, from the physical model experiment andmathematical model calculations show that: a high degree of energy dissipationthreshold should choose the aperture of about0.5times the water hole, the location ofthe energy dissipation threshold should choose away from the water orifice distance ofabout three times the water hole diameter, cross-sectional area of the water hole shouldchoose about0.95times the valve main corridor cross-sectional area, at this time energydissipation for the best flow conditions of the lock chamber best.The result of this paper can provide a reference and basis for the energy dissipationthreshold and the water hole layout in the conveyance system design process inlow-head navigation lock side wall long corridor... |
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