旋流排沙渠道中旋转水流的排沙效果研究  

Study on the Sediment Discharge Effect of the Swirling Flow in a Desilting Channel with Swirling Flow

作　　者：南军虎[1] 马康宁 汪超群 李伟 陶然 代江龙 NAN Junhu;MA Kangning;WANG Chaoqun;LI Wei;TAO Ran;DAI Jianglong(College of Energy and Power Eng.,Lanzhou Univ.of Technol.,Lanzhou 730050,China)

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050

出　　处：《工程科学与技术》2024年第3期170-178,共9页Advanced Engineering Sciences

基　　金：国家自然科学基金资助项目(52069011);兰州市青年科技人才创新项目(2023-QN-33)。

摘　　要：旋流排沙渠道是基于旋转水流强挟带能力的特点提出的一种渠道水沙分离新技术,为了明晰其水沙特性,在试验研究的基础上,采用Realizable k-ε模型、VOF法及离散相模型,对旋流排沙渠道内的水沙两相流特性进行了数值模拟,通过与模型试验成果的对比确定了不同粒径泥沙的球度,研究了持续来沙条件下旋流排沙渠道的排沙效果,分析了渠道和排沙洞内泥沙的分布规律。结果表明:不同粒径泥沙的球度介于0.2~1.0之间时,在渠道顶部局部来沙条件下旋流排沙渠道对粒径为(0.075,3.000]mm泥沙的计算截沙率与试验值吻合良好,二者的相对误差仅为3.5%,误差主要来源于(0.075,0.160]mm的极细颗粒泥沙;当上游渠道水流进口来沙质量流量为60 g/s时,渠底高含沙水流由起旋室的分流,渠道含沙量迅速降低,起旋室前部和后部渠底水流含沙量分别为44.00 kg/m^(3)和0.07 kg/m^(3);排沙洞内的旋转水流对泥沙的挟带作用明显,在强离心作用下泥沙主要分布在排沙洞近壁面,最大泥沙含量约为200.00 kg/m^(3);在持续来沙条件下旋流排沙渠道对粒径为(0.075,3.000]mm泥沙的截沙率为95.98%,仅少量极细泥沙以悬移质形式进入下游渠道,渠道和排沙洞内无大量的泥沙淤积,表明旋流排沙渠道是一种可实现高效且连续排沙的水沙分离技术。本成果可为旋流排沙渠道在工程中的应用和水沙特性的研究提供有益参考。The desilting channel with swirling flow is an innovative technology for separating water and sediment in channels based on the strong carrying capacity of swirling flow.The two-phase flow of water and sediment in the desilting channel is simulated using the realizable k-εmodel,volume of fluid method,and discrete phase model based on experimental tests to indicate its water-sediment characteristics.The shape factors of sediments with varying particle sizes are determined by comparison to model test results.The effectiveness of sediment discharge in the desilting channel under continuous sediment inflow is examined,and the movement characteristics of sediment within the channel and the sediment trans-port pipe are analyzed.The results demonstrated that when the shape factors of sediments with different particle sizes range from 0.2 to 1.0,the simulated sediment trapping efficiency for particle sizes of(0.075,3.000]mm in the desilting channel with swirling flow closely aligns with the experimental values under local inflow conditions from the top of the channel,with a relative error of only 3.5%,primarily attributed to fine sedi-ment particles sized(0.075,0.160]mm.When sediment is continuously imported from upstream channels at a mass flow rate of 60.0 g/s,the sedi-ment content in the channel rapidly decreases due to the diversion by the swirling flow generator for hyperconcentrated flow at the bottom of the channel.The sediment content at the channel bottom before and after the swirling flow generator is 44.00 and 0.07 kg/m^(3),respectively.The swirl-ing flow in the sediment transport pipe exhibits a notable sediment-carrying effect,with sediment primarily distributed near the wall of the pipe due to the strong centrifugal action of the swirling flow,where the maximum sediment content reaches approximately 200.00 kg/m^(3).The sedi-ment trapping efficiency of the desilting channel with swirling flow is 95.98%for particle sizes of(0.075,3.000]mm under continuous sediment inflow conditions.Only a small amount of fin

关 键 词：旋流排沙渠道 水沙特性 数值模拟 离散相模型 截沙率 

分 类 号：TV91[水利工程—水利水电工程]