Study on stage-discharge formula of measuring flume in U-shaped channel considering the influence of channel bottom slope
The channel bottom slope is an important factor affecting the water delivery capacity,but the channel bottom slope is often ignored in the stage-discharge formula of measuring flume.To investigate the influence of channel bottom slope on the stage-discharge formula,field experiments were conducted on U-shaped channels with six types of channel bottom slopes,using triangular prism flumes as the research object.The theoretical formu-la of flow was deduced by using energy equation.Based on dimensional analysis and discharge coefficient,the stage-discharge formula without and with channel bottom slope were established respectively.The range of channel bottom slope that affects the stage-discharge formula was explored.The theoretical formula of flow shows that the channel bottom slope is one of the factor that affects the stage-discharge formula of the water measuring flume.Compared with the stage-discharge formula without channel bottom slope,the flow measurement accuracy of the stage-discharge formula with channel bottom slope is significantly improved.The average relative error decreases from 2.92％to 1.65％,the maximum relative error decreases from 12.22％to 7.37％,and the proportion of abso-lute relative error less than 5％increases from 80.94％to 95.89％.The range of channel bottom slope that affects the stage-discharge formula of the triangular prism flume is defined as 1/100 to 1/1200,and can be ignored when the channel bottom slope is less than 1/1200.The influence of channel bottom slope should be considered in the stage-discharge formula of measuring flume in open channel along slope.
万方数据
维普
