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.
维普
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