明渠非恒定流及输沙试验系统

Experimental system to study unsteady open-channel flow and sedimentation

为研究明渠非恒定流运动特性和输沙机理,建立了长20m,宽29.5cm,高40cm的水槽非恒定流实验系统。该系统包括变坡水槽、供水控制、水位和流速量测、推移质循环及测量5个部分。通过计算机控制生成设定的非恒定流过程;沿水槽架设的6个压力传感器监控沿水槽的水位变化;采用二维激光流速仪测量垂线流速分布。初步试验结果表明:该系统可以生成稳定可重复的非恒定流过程,得到包括水深、流量、流速及输沙率变化的大量非恒定流试验数据,为洪水波的运动特性及输沙特性研究奠定了基础。

A flume system was built to experimentally study unsteady flow and sedimentation. The flume is 20 m long, 29.5 cm wide, and 40 cm high. The system has a water supply facility, water level gauges, a 2-D Laser Doppler Anemometer (LDA) and a bed-load circulation measurement system. During experiments, hydrographs of the unsteady flow can be generated using a computer, the water level can be measured with 6 pressure transducers installed along the flume, and the vertical velocity distribution can be measured with the LDA. Preliminary experimental data showed that a large amount of experimental data can be obtained by repeatedly generating a series of unsteady hydrographs, including water depth, discharge, velocity and bed load transport. This experimental system provides a foundation for further study on flood characteristics and sediment transport in unsteady open-channel flows.