不同坡度下摆杆式测流仪量水特性的研究

Research on Water Measurement Characteristics of Pendulum-rod Flowmeter with Different Slope

灌区精准量水是实现水资源可持续发展的关键所在,针对明渠测流技术提出了一种基于摆杆摆动角度与渠道过水断面瞬时流量之间关系的明渠测流方法。为了研究不同坡度下摆杆式明渠测流装置的测流特性,利用摆杆式测流仪器在D50 U型渠道上进行测流试验,并结合量纲分析法对试验结果进行处理,研究表明:摆杆式明渠测流仪摆动角度θ与渠道过水断面瞬时流量Q之间关系为:Q=K(L sinθ)5/2,在坡度为1/500、1/1 000、1/2 000、1/5 000与1/10 000的D50 U型渠道中线性相关性良好,测量精度可以满足明渠测流要求。

Accurate water quantity measurement in irrigation area is the key to achieve sustainable development of water resources. In this paper,an open channel flow measuring method based on the relationship between the swing angle of the pendulum and the instantaneous flow of the channel cross section is proposed for the open channel flow measurement technology. In order to study the characteristics of flow measurement in open channel with different slope,the flow measurement test is carried out in the D50 U-shape-channel by using the pendulum bar flowmeter. The test results are treated with dimensional analysis. The research shows that: the relationship between the angle of the pendulum pole of open-channel flowmeter and the instantaneous flow Q of the water cross section of the channel is Q = K( L sinθ)5/2. In the D50 U-shape-channel with slope of 1/500,1/1 000,1/2 000,1/5 000 and 1/10 000,the correlation is good,and the coefficient K decreases as the gradient increases. The measurement accuracy can meet the requirements of open channel flow measurement.