长直管道输砂的沿程临界流速

Critical velocity of sand transportation along long straight pipeline

近年来,河湖水库的环保疏浚、港口航道建设与维护性疏浚工程越来越多,管道输送是疏浚泥沙搬运的主要方式,输送距离也越来越长。管道输送中流速沿程的再分布情况和临界流速尚待进一步研究。基于古雷镇填沙工程清水工况及输沙工况分层取样浓度实测数据对模型进行率定。在此基础上对长直管道输送砂类泥沙颗粒进行三维水动力及砂的运动模拟,分析了直管道沿程的剖面流速再分布特征和泥沙淤积临界流速规律,提出长管中不同断面位置发生泥沙淤积的临界流速公式,为疏浚工程设计提供参考依据。

In recent years, there have been more and more environmental protection dredging projects in rivers and reservoirs and port and waterway construction and maintenance dredging projects. Pipeline transportation is the main method of dredging sediment transportation, and the transportation distance is also getting longer and longer. The redistribution of the flow velocity and the critical flow velocity along the pipeline needs to be further studied. The model is calibrated based on the measured data of the clean water conditions and the stratified sampling concentration of the sand transport conditions of the Gulei sand filling project. On this basis, three-dimensional hydrodynamic and sand motion analysis are performed on the long straight pipeline transportation of sand particles. The redistribution characteristics of the section velocity along the straight pipeline and the law of the critical velocity of sediment deposition are analyzed. The formula of the critical velocity of sediment deposition at different sections in the long pipe is put forward, which provides a reference for the design of dredging projects.