摘要
文章从梭锥管浑浊流体分离装置(简称梭锥管)内泥沙沉降的力学特性出发,针对梭锥管水力分离水沙的力学机理进行了研究。研究结果表明:梭锥管内部的流场分布为锥圈间的水沙循环和整个梭锥管内部的水沙循环流动。梭锥管的水沙分离效果与其本身的倾斜角度α和锥圈的倾斜角度β有关,与前期实验结果相一致。泥沙在无锥圈梭锥管中与有锥圈的梭锥管中下沉相同H距离所需时间t'与t之比大于1,说明在梭锥管内布置若干个一定角度的锥圈能极大的缩短沉降时间,达到了快速分离浑水的效果。但当锥圈个数n继续增大时,t'与t之比不再随之增大,说明锥圈个数与水沙分离效果存在最优组合。随着β逐渐变小泥沙的下滑速度会随之降低,当β接近泥沙的水下自然休止角时,锥圈上产生淤积。随着梭锥管倾斜角度α的变化泥沙沉降轨迹发生相应变化。文章研究结果初步探明了梭锥管混浊流体分离装置快速水力分离水沙的机理,并从理论上论证了前期物理试验中得出的结构优化参数的合理性。
Hydraulic separation of water and sediment in a turbid fluid separation device,namely a shuttle-conical tube,was studied experimentally in consideration of sediment setting characteristics.Results indicate that the flow field is featured with a circulation of water-sediment flow in each spacing of the conical circles and circulations inside of the tube.And the separation effect depends on the tilt angle α of the tube and the tilt angle β of the conical circles,which is consistent with the previous experimental results.Compared with the case of no conical circle,the settling time needed for a given falling distance is shorter.This means that if the conical circles are disposed in a certain angle,the settling time can be shortened greatly and fast settling can be achieved.If the number of conical circles is increased further,however,the settling time cannot be shortened any more.This implies that there should exist an optimal combination of this number with the effect of fast settling.As β decreases gradually,the slip velocity of sediment also decreases gradually.Sand deposits on the conical circles when β approaches the natural angle of repose of the sediment underwater.Sediment depositing path varies with the tube tilt angle α.This study also gives a preliminary explanation of the mechanism for fast hydraulic separation of water and sediment in this tube,and theoretically proves the optimized tube structure and parameters that the authors obtained in the previous experimental study.
出处
《水力发电学报》
EI
CSCD
北大核心
2013年第2期184-189,共6页
Journal of Hydroelectric Engineering
基金
国家自然基金项目(51009117)
新疆维吾尔自治区自然科学基金(2010211B08)
关键词
环境水力学
水沙两相流
运动轨迹
沉降特性
梭锥管
environmental hydraulics
water-sediment two-phase flow
movement path
settling characteristics
shuttle-conical tube
