Multi-point Flow Measuring Method of River Section Based on Fixed Point

Abstract

The invention discloses a river cross section multipoint flow-measuring method based on fixed points. The method is implemented based on a radar flow-measuring meter which is fixedly installed above a river. The method comprises the steps that the altitude H of the place where the radar flow-measuring meter is located and the perpendicular distance w between the radar flow-measuring meter and the river cross section to be measured are obtained through measurement; the distance between each measuring point and the datum point O on the river cross section is obtained through measurement; flow measurement is conducted on all the measuring points in sequence, wherein before the flow velocity of each measuring point is measured, the horizontal orientation of the radar flow-measuring meter is adjusted first, and then the perpendicular dip angle of the radar flow-measuring meter is adjusted, so that the detection direction of the radar flow-measuring meter is right opposite to the measuring point, and flow measurement is conducted. The river cross section multipoint flow-measuring method is only based on one radar flow-measuring meter, and multipoint flow-measuring operation can be realized at multiple measuring points on the same river cross section just through adjustment of the horizontal orientation and the perpendicular dip angle of the radar flow-measuring meter.

Description

technical field [0001] The invention relates to a method for measuring and calculating river flow, in particular to a method for realizing flow measurement at multiple measuring points on a river section based on a certain fixed point. Background technique [0002] At present, the measurement of river surface flow is mostly realized by measuring the ship-borne ADCP system. Although the ship-borne ADCP system has the advantages of fast flow measurement, high accuracy, and convenient operation, it can be found from actual implementation that when there are many floating objects in the river, the water quality is turbid, or the water flow rate is too fast, the measurement of the ship-borne The accuracy of the measurement results obtained by the ADCP system will be greatly reduced, and it may even fail to work normally. Moreover, when a flood occurs, the vessel-borne ADCP system cannot measure the water velocity in time. [0003] In recent years, with the emergence of cableway...

AI Technical Summary

Problems solved by technology

However, it can be found from the actual implementation that a cableway needs to be installed above the river before implementing this method of flow measurement. , because the cableway itself has a certain gravity, the cableway itself cannot be kept in a straight line, and the cableway current meter cannot run in a straight line, so that there will be a certain deviation in the measurement results, and it is also easily affected by the wind

[0004] For the existing fixed current measurement method realized based on the fixedly installed current measuring instrument, it has the following defects: First, the fixed current measuring method can only measure the flow at one measurement point based on the fixedly installed current measuring instrument. The detection direction of the current meter cannot be changed, but in the case of complex terrain and wide river channels, the flow velocity at any measurement point on the river channel section cannot represent the flow velocity of the entire river channel section. way to make up for it, but it will result in an increase in equipment purchase costs

Second, when the water level changes, the actual measurement point will deviate from the original river section

For example, if figure 1 , based on the fixed flow measurement method implemented by the fixedly installed current meter 10, the flow is always measured according to the inherent set vertical inclination angle. When the water level is water level 1, the measurement point is point A. When the water level rises from water level 1 to water level 2 , the actual measurement point changes to point B, and point B obviously deviates from the river section (original river section) corresponding to water level 1, thus causing a deviation in the measurement results and unable to reflect the real flow velocity of the original river section

Third, the fixed flow measurement method cannot dynamically change the measurement point, and has low adaptability to complex situations

Images