發(fā)布時(shí)間：2018-02-05 05:07

  本文關(guān)鍵詞： 水庫水溫 分層取水 帷幕　出處：《工程科學(xué)與技術(shù)》2017年S1期 　論文類型：期刊論文

【摘要】：為探索減緩已建水庫對(duì)下游產(chǎn)生的低溫水不利影響的新措施,以某已建大型水庫為例,開展不同帷幕布設(shè)方式對(duì)改善下泄低溫水效果的研究。采用立面2維數(shù)學(xué)模型計(jì)算某大型水庫壩前垂向水溫結(jié)構(gòu)及下泄水溫過程,設(shè)計(jì)不同遮擋高度、淹沒深度及距壩軸線距離等6個(gè)帷幕方案,并對(duì)各方案的流場(chǎng)及溫度場(chǎng)進(jìn)行對(duì)比分析。結(jié)果表明:帷幕設(shè)置將顯著影響庫區(qū)的浮力流動(dòng)及垂向溫度分布,3種局部遮擋方案下取水口的抽吸作用導(dǎo)致底層低溫水體繞過帷幕被較多地引用,均不能有效提高下泄水溫,底部全遮擋方案的設(shè)置對(duì)提高水庫下泄水溫效果明顯,但同時(shí)由于持續(xù)取用表層溫水,庫區(qū)水溫顯著降低。淹沒水深應(yīng)結(jié)合取水層厚度確定,當(dāng)淹沒水深與帷幕上層取水層厚度相近時(shí)有較好的低溫水改善效果。壩前1 km范圍內(nèi)帷幕軸線位置對(duì)下泄水溫的影響不明顯。建議水溫控制帷幕的設(shè)計(jì)采用底部全遮擋,中底部全遮擋帷幕方案的下泄水溫5—8月較無措施時(shí)分別升高了3.4、2.1、1.1、0.4℃,帷幕提高下泄水溫效果明顯。
[Abstract]:In order to explore the new measures to mitigate the adverse effects of the built reservoir on the downstream low temperature water, a large reservoir has been built as an example. The vertical water temperature structure in front of a large reservoir dam and the process of drainage temperature are calculated by using two dimensional elevation mathematical model, and different shielding heights are designed. Six curtain schemes, such as submerged depth and distance from the dam axis, are compared and analyzed. The results show that the curtain setting will significantly affect the buoyancy flow and vertical temperature distribution in the reservoir area. The suction of the water intake under three local occlusion schemes leads to the low temperature water at the bottom of the water being used more frequently to bypass the curtain, which can not effectively raise the temperature of the drainage. The setting of the bottom complete occlusion scheme has obvious effect on increasing the temperature of the reservoir drainage, but at the same time, the water temperature of the reservoir decreases significantly because of the continuous use of the surface warm water. The depth of the submerged water should be determined in combination with the thickness of the water intake layer. When the depth of submerged water is close to the thickness of the intake layer of the curtain upper layer, the improvement effect of low temperature water is better. In the range of km, the influence of the position of the curtain axis on the discharge temperature is not obvious. It is suggested that the design of the water temperature control curtain should adopt the bottom full occlusion. In May to August, the temperature of draining water in the middle and bottom complete shielding curtain was increased by 3.4 ~ 2.1L ~ (1.1) ~ 0.4 鈩，

本文編號(hào)：1492211