Abstract: At present, the Doppler flowmeter has been increasingly used in the measurement of the discharge of the drainage pipeline in China, but it is difficult to use the Doppler flowmeter in the field because of the obstruction and the filling of water in the drainage pipeline. Based on indoor full-size drainage pipeline test platform, the monitoring effectiveness of the Doppler flowmeter under the complicated conditions was evaluated. Different pipeline blocking degrees were simulated by installing a series of baffles. Under the condition of known inflow, error analysis shows that the velocity is the main factor influencing the monitoring efficiency of the Doppler flowmeter, and low flow and severe pipeline blocking will cause a decline in the accuracy of velocity monitoring. Using the measured liquid level data of free and constant flow, various liquid level-flow relation models were fitted. Based on the information criterion, the superiority evaluation of the models was carried out, and it is shown that the quadratic polynomial is the optimal model under this experimental condition. Based on the measured value of hydraulic elements under different flow conditions, the variation law of liquid level and flow during the pipeline blocking was analyzed, which provides reference for the establishment of the model of liquid level-flow in the pipeline under complicated flow conditions.
Keywords: drainage pipeline; Doppler flowmeter; flow monitoring; liquid level monitoring; information criterion
合肥工业大学学报自科版