一、引言在流速测量中,流速仪测量某点流速的准确度很高,检定的均方差一般都在±2.0%以内。同时,在明渠的结构设计中,明渠大多为规则的矩形或梯形断面,根据断面流量测量原理,规则断面带来的断面流量测量误差很小。此外,根据国家标准GB50179-1993《河流 I. INTRODUCTION In the measurement of the flow rate, the accuracy of the flowmeter in measuring the flow velocity at a certain point is very high. The mean square deviation of the test is generally within ± 2.0%. In the meantime, in the structural design of open channels, the open channels are mostly regular rectangular or trapezoidal sections. According to the cross-section flow measurement principle, the cross-section flow measurement error caused by the regular sections is small. In addition, according to the national standard GB50179-1993 "river