Sound path length self-correcting ultrasonic flowmeter

Abstract

The utility model discloses a sound path length self-correcting ultrasonic flowmeter which comprises a flowmeter measuring host, a plurality of flow velocity measuring ultrasonic transducers with temperature sensors, a plurality of flow velocity measuring ultrasonic transducers and a signal cable, and the flow velocity measuring ultrasonic transducers and the flow velocity measuring ultrasonic transducers with the temperature sensors are matched in pairs. The flow velocity measurement ultrasonic transducer and the flow velocity measurement ultrasonic transducer with the temperature sensor are connected with the flowmeter measurement host through a signal cable according to the definition of an instrument. The flowmeter host has the functions of temperature measurement, sound path length self-correction and flow velocity and flow measurement. The installation and construction requirements of the time-difference method ultrasonic flowmeter are further simplified, and the installation and construction cost is reduced; after the instrument is installed in a water body, the instrument automatically measures the water temperature and corrects the sound path length measurement error, the flow measurement precision is high, and the anti-interference capacity is high.

Description

TECHNICAL FIELD

[0001] The utility model relates to hydrology monitoring technical field especially relates to a sound road length self -correcting time difference method ultrasonic flowmeter. BACKGROUND

[0002] Time difference method ultrasonic flowmeter calculates the flow rate of water flow according to the propagation time difference of ultrasonic wave in water flow in the direction of flow and the direction of counterflow, and obtains the flow of water flow in combination with the area of water section. When measuring, the flow rate measuring ultrasonic transducer at upstream and downstream will sequentially emit ultrasonic pulse, one is counterflow propagation, and one is flow propagation. The ultrasonic pulse propagation speed in flow is faster than the speed of counterflow propagation, and since the actual path of the two pulse propagations is same, the difference of transmission time directly reflects the size of fluid flow rate. By measuring the flow rate of water flow, the flow of water flow is obtained in combination with the area of section. The traditional ultrasonic flowmeter only contains measurement host and flow rate measuring ultrasonic transducer, and the sound road length cannot be checked whether correct through manual input, which causes larger measurement error. SUMMARY

[0003] The utility model aims at providing a sound road length self -correcting time difference method ultrasonic flowmeter.

[0004] Technical scheme: the utility model discloses flowmeter measurement host 1, a plurality of temperature sensor flow rate measuring ultrasonic transducer 2, a plurality of flow rate measuring ultrasonic transducer 3 and signal cable 4.

[0005] Further, the flow rate measuring ultrasonic transducer 3 and the temperature sensor flow rate measuring ultrasonic transducer 2 are matched in pairs.

[0006] Further, the flow rate measuring ultrasonic transducer 3 and the temperature sensor flow rate measuring ultrasonic transducer 2 are connected with the flowmeter measurement host 1 through the signal cable 4.

[0007] Further, the flow rate measuring ultrasonic transducer 3 and the temperature sensor flow rate measuring ultrasonic transducer 2 can be provided with multiple pairs.

[0008] Further, the flow rate measuring ultrasonic transducer 3 and the temperature sensor flow rate measuring ultrasonic transducer 2 have waterproof design and can be used underwater for a long time.

[0009] Further, the flowmeter measurement host 1 is time difference method ultrasonic flow rate, flow rate measurement host.

[0010] Further, the flowmeter measurement host 1 is multi-channel measurement host.

[0011] Further, the flowmeter measurement host 1 is temperature measurement host.

[0012] Further, the flow meter measurement host 1 is a sound path length self-correcting measurement host.

[0013] Beneficial effects: compared with the prior art, the utility model has the following advantages: further simplify the installation construction requirement of time difference method ultrasonic flow meter, reduce the installation construction cost; after the instrument is installed in the water body, the instrument automatically measures the water temperature, automatically corrects the sound path length measurement error, the flow measurement precision is high, and the anti-interference ability is strong. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is a structural schematic view of flow meter measurement host;

[0015] Figure 2 It is a schematic view applied in pipeline and channel, 2 (a) is pipeline, 2 (b) is channel;

[0016] Figure 3 It is a structural schematic view of flow speed measurement ultrasonic transducer with temperature sensor;

[0017] Figure 4 It is a structural schematic view of flow speed measurement ultrasonic transducer

[0018] Figure 5 It is a sound path length correction flow chart. DETAILED DESCRIPTION

[0019] The technical scheme of the utility model will be further explained in connection with the drawings.

[0020] The utility model discloses a device, including flow meter measurement host 1, multiple flow speed measurement ultrasonic transducers with temperature sensor 2, multiple flow speed measurement ultrasonic transducers 3, signal cable 4, flow speed measurement ultrasonic transducer 3 and flow speed measurement ultrasonic transducer with temperature sensor 2 are connected according to instrument definition with flow meter measurement host 1 by signal cable 4, as shown in Figure 1 、 3 , 4. Flow meter host 1 has time difference method ultrasonic flow speed, flow measurement function;Flow meter host 1 has temperature measurement function;Flow meter host 1 supports multiple sound path measurement;Flow meter host 1 has the function of sound path length self-correction.

[0021] As shown in Figure 2 , flow speed measurement ultrasonic transducer 3 and a flow speed measurement ultrasonic transducer with temperature sensor 2 are installed in pipeline or channel in pairs;2 (a) is pipeline, 2 (b) is channel;

[0022] Adjust the position of each layer flow speed measurement ultrasonic transducer 3 and flow speed measurement ultrasonic transducer with temperature sensor 2, make the correspondence of transceiver pair;

[0023] The flow velocity measurement ultrasonic transducer 3 and the flow velocity measurement ultrasonic transducer 2 with a temperature sensor are connected to the measurement host 1 through the signal cable 4 according to the instrument definition;

[0024] The sound path length of each pair of the flow velocity measurement ultrasonic transducer 3 and the flow velocity measurement ultrasonic transducer 2 with a temperature sensor is measured, recorded and input into the measurement host 1;

[0025] The measurement host 1 is connected to a power supply and started;

[0026] The sound path length correction function is run, and the flow is as shown in the figure; Figure 5

[0027] The instrument is normally operated, and the flow velocity and flow are automatically calculated;

[0028] The time difference method ultrasonic flowmeter with sound path length self-correction has the functions of flow velocity, flow, temperature and water level measurement. The instrument has the advantages of not destroying the flow field, high measurement accuracy, wide range, high resolution, fast response speed and the like. Compared with the existing time difference method ultrasonic flowmeter, the instrument has the advantages of sound path length self-correction, reduced installation and debugging difficulty and increased applicability.

[0029] From the measurement principle of the time difference method ultrasonic flowmeter, it can be known that:

[0030]

[0031] Wherein, v is the average velocity of water flow, L is the sound path length, is the angle between the sound wave path and the water flow direction, Tu is the time experienced by the ultrasonic wave along the downstream direction, Td is the time experienced by the ultrasonic wave along the upstream direction, and C is the current sound speed in water.

[0032] The common item C can be obtained by extracting the common item C from the two formulas:

[0033]

[0034] Tu and Td are instrument measurement values, the accuracy of which is related to the design of the instrument, L, is the measured value, which needs to be measured and input after installation. L, There is a measurement error, which directly affects the accuracy of v and causes flow measurement error. The measurement error is small, so obtaining an accurate L value is one of the key factors to ensure the accuracy of the time difference method ultrasonic flowmeter. This requires a higher installation and construction requirement for the time difference method ultrasonic flowmeter, especially when the installation is carried out in water, it is difficult to measure the sound path length with high precision, which affects the universality of the time difference method ultrasonic flowmeter.

[0035] The common item v can be obtained by extracting the common item v from the two formulas:

[0036] ​

[0037] C is the current speed of sound in water, which is related to water temperature, and there is a speed of sound and water temperature corresponding table. The speed of sound calculated by the flowmeter host for each layer can be corresponded to the water temperature of each layer according to the speed of sound and water temperature corresponding table. If the water temperature calculated by the flowmeter host is consistent with the actual water temperature, it means that the sound path length L at this time is accurate. If the error exceeds 0.5℃, it means that the sound path length L at this time has a large error, and the flow rate obtained at this time also has a large error. The host program automatically adjusts the sound path length L of this layer, and the speed of sound measurement in this layer is performed again. Multiple iterations are performed until the difference between the water temperature corresponding to the speed of sound calculated by the flowmeter host and the measured value of the temperature sensor is within 0.5℃. At this time, the sound path length L of each layer is the accurate value. The sound path length self-correction of all sound paths is sequentially performed, and the corrected sound path length L is saved as the accurate sound path length value for calculating v in the future. At this time, the flow rate and flow measurement accuracy is the highest.

Claims

1. An ultrasonic flowmeter with self-calibration of acoustic path length, characterized by: The invention comprises a flow meter measuring host (1), a plurality of flow velocity measuring ultrasonic transducers with temperature sensors (2), a plurality of flow velocity measuring ultrasonic transducers (3), and a signal cable (4); the flow velocity measuring ultrasonic transducers (3) and the flow velocity measuring ultrasonic transducers with temperature sensors (2) are matched in pairs; the flow velocity measuring ultrasonic transducers (3) and the flow velocity measuring ultrasonic transducers with temperature sensors (2) are connected to the flow meter measuring host (1) via the signal cable (4).

2. The ultrasonic flowmeter with self-calibration of acoustic path length according to claim 1, characterized in that: The flow meter measuring host (1) is a time difference method ultrasonic flow velocity and flow measurement host.

3. The ultrasonic flowmeter with self-calibration of acoustic path length according to claim 1, characterized in that: The flow meter measurement host (1) is a multi-channel measurement host.

4. The ultrasonic flowmeter with self-calibration of acoustic path length according to claim 1, characterized in that: The flow meter measuring host (1) is a temperature measuring host.

5. The ultrasonic flowmeter with self-calibration of acoustic path length according to claim 1, characterized in that: The flow meter measuring host (1) is an acoustic path length self-correcting measuring host.

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