雨水系统旋流沉砂池的设计及性能研究

Design and Performance of Vortex Grit Chambers for Stormwater System

为避免雨水中的重质固体颗粒物沉积,进而使排水通畅、缓解城市内涝,设计了一种用于雨水管道的旋流沉砂池,通过环形堰、导流筒等特定的结构,实现小雨量时有效除砂、大雨量时自动减小阻力而有效泄洪;利用底部的消能格栅抑制过流紊动,有效避免沉淀后的颗粒物再次悬浮而随水流溢出;进出水管道同高程布置,有利于既有管道系统的改造。通过CFD软件进行流态模拟及实验室模型试验,研究了沉砂池的内部流态及对各类重质颗粒物的去除效果。结果表明,该旋流沉砂池能达到预期的设计目标。

A vortex grit chamber was designed to avoid the deposition of heavy solid particles in stormwater system, to ensure the drainage capability, and to alleviate urban flooding risks. The device could effectively remove sands in light rains and release floods, by automatically adjusting the resistance through its specific structures such as the annular weir and the draft tube. The design could trap particles by using a bottom grid to dissipate the energy and to reduce flow turbulence. The inlet and outlet pipes were arranged at the same level, to facilitate retrofitting existing pipeline systems. The flow pattern was modeled in CFD software and tested in laboratory model, to study the internal flow of the grit chamber and the removal efficiency of different heavy particles. The results showed that the new design of the vor- tex grit chamber achieved the desired design objectives.