基于时差法的明渠流量测量系统研究

Study on Open Channel Flow Measurement System Based on Time Difference Method

以华北平原为研究对象,建立时差法流量监测系统,对其水量进行自动化监测,分别测量在单声道和多声道下,明渠流量的变化情况,并考虑不同流速下,该监测系统的精度变化规律。结果表明,多声道监测的测量流量变化趋势与单声道具有一致性,但其参考流量均大于多声道流量监测值。单、多声道的流量绝对误差无明显的变化趋势,其波动较大,与测量次数之间无相关关系。其中,单声道测量的绝对误差波动范围较大,多声道测量的绝对误差波动范围较小。对比单声道测量误差可知,多声道测量误差较小,且在4档流速下有最小相对误差。在实际工程中,可采用4档流速下的多声道进行流量测量。

In this study,a time-difference flow monitoring system was set up in North China Plain to automatically monitor the water flow in open channels under mono and multi-channel conditions,the variation law of the accuracy of the monitoring system is also considered under different flow velocities.The results show that the measured flow rate of multi-channel monitoring is consistent with that of single channel,but the reference flow rate of multi-channel monitoring is higher than that of multi-channel monitoring.The absolute error of single and multi-channel flow has no obvious change trend,and its fluctuation is large,and there is no correlation between the number of measurements.The range of absolute error of single-channel measurement is larger than that of multi-channel measurement.Compared with the single channel measurement error,the multichannel measurement error is smaller,and has the minimum relative error at 4-speed.In practical engineering,the multi-channel measurement at 4-speed can be used for flow measurement.