Four-round-rod and double-semi-ring combined three-dimensional calibration method for single-point ocean current meter

Abstract

A four-round-rod and double-semi-ring combined three-dimensional calibration method for a single-point current meter comprises the following steps: fixing a whole tool on a trailer through a positioning hole between an inner ring and an outer ring of a top flange plate, and then immersing the whole tool clamping the single-point current meter to be calibrated below the water surface of a towing tank; the overall rotating device enables the positioning hole to face forwards so as to complete calibration adjustment in the X direction and the Y direction or keeps the posture of the hoop clamping the ocean current meter unchanged, and the positioning hole in the side face of the hoop is connected with the flange plate by changing the connecting rod so as to complete calibration in the Z direction. Different axial conversion can be quickly realized, and the three-dimensional flow velocity calibration efficiency of the ocean current meter is remarkably improved.

Description

Technical Field

[0001] The invention relates to a technology in the field of ocean measurement, in particular to a three-dimensional calibration method of a four-circular-rod and double-half-ring combination for a single-point current meter. Background Art

[0002] The existing single-point current meter calibration method usually relies on static testing in a laboratory environment or dynamic calibration under field conditions. Although the former can provide more accurate results, it takes a lot of time and is difficult to simulate the complex actual ocean environment; the latter is affected by various factors such as weather and water flow changes, which increases the difficulty and uncertainty of operation. Therefore, the calibration of current meters is basically carried out in indoor water tanks or towing pools. The existing single-point current meter calibration device has many structural deficiencies: for example, it can only realize two-dimensional calibration in the X-axis and Y-axis directions, and cannot calibrate the Z-axis. It can only be applied to a specific single model of current meter, and cannot meet the needs of various types of instruments, which limits its application range; the tooling strength and stability are insufficient, the device is not firm enough when fixing the current meter, and it is easy to move during the high-speed calibration process, thereby affecting the accuracy of the data. It can only calibrate low-speed flow and is difficult to apply to cylindrical instruments of different outer diameters, and cannot ensure stability and reliability in different harsh environments, such as high-speed calibration or complex water flow conditions. Summary of the invention

[0003] In view of the problems of complex operation and low conversion efficiency in the calibration of existing single-point current meters, the present invention proposes a three-dimensional calibration method of a four-circular rod and double half-ring combination for a single-point current meter, which can quickly realize different axial conversions and significantly improve the three-dimensional flow velocity calibration efficiency of the current meter.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention relates to a three-dimensional calibration method of a four-round-rod double-half-ring combination for a single-point current meter. The tooling as a whole is fixed on a trailer through a positioning hole between an inner and outer ring of a top flange. The tooling as a whole with the single-point current meter to be calibrated is then immersed below the water surface of a towing pool. An overall rotating device is used to make the positioning hole face forward to complete the adjustment of XY direction calibration or to keep the posture of a clamp clamping the current meter unchanged and to connect the positioning hole on the side of the clamp with the flange by changing a connecting rod to complete the Z direction calibration.

[0006] The single-point current meter is a spiral four-axis three-dimensional current measurement system, including: an electrical compartment, a piezoelectric ultrasonic transducer array arranged on the top thereof, and a measurement circuit and a control circuit arranged inside thereof, wherein: the piezoelectric ultrasonic transducer array, the measurement circuit and the control circuit are connected in sequence.

[0007] The piezoelectric ultrasonic transducer array comprises: a support frame and four pairs of transducers arranged oppositely, wherein: each pair of transducers are arranged oppositely on the upper and lower sides of the support frame to form a measurement acoustic axis, and the four measurement acoustic axes have the same angle with the horizontal plane. Technical Effects

[0008] The present invention realizes flexible connection through the combination design of multiple holes. The selection of different hole positions is connected by connecting rods to meet various installation requirements. The operation is simple and the installation efficiency is high. At the same time, the fastening design of bolts and nuts between the two clamps realizes the stable clamping of the electrical compartment of the current meter, ensuring high-strength vibration resistance and fixing reliability in actual use. When fixing the current meter, the present invention fixes the positions of the two clamps by connecting rods, and uses nuts and bolts to connect through the fixing holes on both sides of the clamps, so that the current meter is firmly fixed in the center area, which is not easy to be displaced and vibrated during the calibration process. At the same time, the device does not involve the lower half of the current meter measurement part, which greatly reduces the influence of the calibration device on the flow field, thereby improving the accuracy of the calibration data and improving the stability of the device calibration under high flow rates. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of the combined calibration device of the present invention when calibrating in the X and Y directions;

[0010] Figure 2 It is a schematic diagram of the combined calibration device of the present invention when calibrating in the Z direction;

[0011] Figure 3 This is a schematic diagram of the actual installation effect of the present invention when calibrating in the X and Y directions;

[0012] Figure 4 This is a schematic diagram of the actual installation effect of the present invention when calibrating in the Z direction;

[0013] Figure 5 A schematic diagram showing the installation effect of adding a hoop lining to the present invention to adapt to different cylindrical instruments;

[0014] Figure 6 This is a measurement data diagram of the present invention when calibrating an actual fixed current meter. DETAILED DESCRIPTION

[0015] like Figure 1 , Figure 2 , Figure 5 As shown, this embodiment involves a four-round rod and double half-ring combined three-dimensional calibration device for a single-point current meter, including: a flange 29, a pair of semi-annular hoops 17, 18 and four connecting rods 13, 14, 15, 16, wherein: the flange 29 is provided with twelve positioning holes for positioning in the X, Y and Z directions respectively.

[0016] Among the three groups of four positioning holes for positioning in the X, Y and Z directions, each group of positioning holes has an equal distance from the center of the flange and the four positioning holes in the same group are evenly distributed in the circumferential direction. The distances between the three groups of positioning holes and the center of the flange are different.

[0017] like Figure 5 As shown, the semi-annular clamps 17 and 18 are further provided with clamp liners 30 and 31 to adapt to cylindrical instruments with different outer diameters.

[0018] like Figure 3 As shown, the single-point current meter is a spiral four-axis three-dimensional current measurement system, including: an electrical compartment 32, a piezoelectric ultrasonic transducer array 33 arranged on the top thereof, and a measurement circuit and a control circuit arranged inside thereof, wherein: the piezoelectric ultrasonic transducer array 33, the measurement circuit and the control circuit are connected in sequence.

[0019] The piezoelectric ultrasonic transducer array 33 includes: a support frame 34 and four pairs of oppositely arranged transducers 35, wherein: each pair of transducers 35 is respectively arranged on the upper and lower sides of the support frame 34 to form a measurement acoustic axis, and the four measurement acoustic axes have the same angle with the horizontal plane.

[0020] This embodiment relates to a calibration method of the above-mentioned calibration device, including:

[0021] Step 1: Figure 3 and Figure 4 The calibration device as shown is connected to the trailer through the top flange trailer positioning holes 9-12, and the whole is completely immersed below the water surface;

[0022] Step 2: When calibrating the X and Y directions, use the connecting rod to connect the two parts through the positioning holes on the outer ring of the flange and the positioning holes on the top of the two clamps. Figure 3 As shown, use the connecting rod to assemble the flange and the clamp, place the electrical compartment of the current meter to be calibrated in the clamp of this device, set the projection of the support rod on the current meter transducer frame to the X-axis and Y-axis, and set the center axis of the center fixing rod to the Z-axis. When installing the current meter, ensure that the projection axis is in a straight line with the vertical direction of the flange positioning hole, so that the direction can be aligned through the positioning hole. During calibration, you only need to rotate the device as a whole so that the corresponding positioning hole faces forward to complete the adjustment in the X and Y directions.

[0023] Step 3: When calibrating the Z direction, use the connecting rod to connect the two parts through the inner ring positioning hole of the flange and the side positioning holes of the two clamps. Figure 4 As shown, the flange and the clamp are assembled using a connecting rod according to the Z-direction positioning hole, the electrical compartment of the current meter is placed in the clamp of this device, and the Z axis of the central axis of the central fixing rod points straight ahead.

[0024] After specific practical experiments, under the specific environmental settings of the towing pool, the calibration experiment was carried out using the above-mentioned four-round rod double half-ring combined clamp calibration fixture under the condition of gradually increasing the flow rate from 0.2m / s to a maximum of 4m / s. In the experiment, the three-dimensional current meter was tested for flow rate in three directions of XYZ by using the calibration fixture. In the XY plane, rapid rotation adjustment is achieved through the peripheral positioning holes of the flange, and each change of direction takes no more than 1 minute; in the Z direction, by changing the position of the connecting rod and assembling it, the entire adjustment process only takes 3-5 minutes.

[0025] In addition, the stability of the device has been fully verified. The assembled device was tested in a towing tank at different flow rates, starting with a trailer speed of 0.2 m / s and gradually increasing to a maximum of 4 m / s. Figure 6 As shown, the device greatly avoids interference caused by vibration and displacement during high flow rate calibration, and has extremely high stability. During the entire test process, the current meter was firmly fixed without obvious displacement or vibration. Especially under high flow rate conditions, the device of the present invention can still remain stable, proving its superiority in high-strength vibration resistance. Moreover, the present invention only clamps the electrical compartment body of the current meter, and has little impact on the natural flow field. Experimental results show that the calibration solution provided by the present invention is not only easy to operate, efficient and flexible, but also has achieved significant improvements in stability, adaptability and calibration accuracy, providing a solid guarantee for the precise measurement of single-point current meters.

[0026] The four-round-rod double-half-ring combined clamp calibration tool of the present invention exhibits excellent portability, high efficiency and flexibility. During transportation, the device can be easily disassembled into flanges, connecting rods, clamps and other parts. Each part is made of lightweight aluminum alloy, and each part is light in weight and occupies little space, and can be easily loaded into a standard tool box.

[0027] During the assembly process, thanks to its modular design and high-precision distribution of positioning holes, the installation steps of the device are simple and clear. The entire assembly process takes only about 3 minutes to complete the tight combination of the flange, clamp and connecting rod and firmly fix the current meter on the calibration fixture. During the calibration process, if calibration in the Z direction is required, it is only necessary to disassemble the connecting rod connecting the side positioning holes of the clamp and reassemble it to the corresponding Z-direction positioning holes. The entire disassembly and reassembly process takes about 5 minutes, which greatly improves the efficiency of axial conversion during calibration. At the same time, the flexibility of this device has also been fully verified by the experiment. The multiple groups of distribution of its positioning holes and the threaded design of the connecting rod make it possible to quickly adjust the structure of the calibration fixture according to specific measurement requirements, so as to achieve stable fixation of the current meter in different directions without the need for additional auxiliary tools. This ability of rapid disassembly and flexible adaptation greatly shortens the preparation time for calibration and measurement, and improves the efficiency and convenience of actual operation. In addition, the stability of the device has also been verified. The assembled device was tested in a towing tank with different flow rates. The trailer started at 0.2m / s and gradually increased to a maximum of 4m / s. The experimental data is shown in Figure 6 It can be seen that the device can largely avoid the interference caused by vibration and displacement during high flow rate calibration and has high stability.

[0028] Compared with the prior art, the present invention realizes comprehensive calibration in the three directions of XYZ, ensuring accurate measurement of the current meter at different angles and orientations, breaking through the limitations of the prior art of single-direction or plane measurement. The calibration direction can be quickly adjusted through the flexible combination of the multi-hole design on the flange and the connecting rod, which greatly improves the operating efficiency and convenience, and enhances the versatility and adaptability of the device, and is suitable for current meters of different models and sizes. In addition, the present invention only clamps the electrical compartment body of the current meter, avoiding interference with the lower half of the measurement structure, minimizing the impact on the calibration environment, and improving the authenticity and reliability of the calibration data. A set of tooling of the present invention can realize efficient calibration in the three directions of XYZ, and the XY direction conversion does not exceed 1 minute, and the Z direction adjustment only takes 3-5 minutes, which greatly shortens the calibration cycle and leaves more time for actual measurement experiments.

[0029] In summary, these innovative designs and technological improvements have achieved significant improvements in ease of operation, flexibility, stability, adaptability and calibration efficiency, providing a more reliable and efficient solution for the precise measurement of single-point current meters.

[0030] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principle and purpose of the present invention. The protection scope of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. Each implementation scheme within its scope shall be subject to the constraints of the present invention.

Claims

1. A four-round-rod and double-half-ring combined three-dimensional calibration method for a single-point current meter, characterized in that: Fix the whole tooling on the trailer through the positioning holes between the inner and outer circles of the top flange, and then immerse the whole tooling with the single-point current meter to be calibrated below the water surface of the towing tank. Rotate the whole device so that the positioning holes face forward to complete the adjustment of XY direction calibration, or keep the posture of the clamp clamping the current meter unchanged and connect the positioning holes on the side of the clamp with the flange by changing the connecting rod to complete the Z direction calibration.

2. The four-round-rod and double-half-ring combined three-dimensional calibration method for a single-point current meter according to claim 1 is characterized in that: The single-point current meter is a spiral four-axis three-dimensional current measurement system, including: an electrical compartment, a piezoelectric ultrasonic transducer array arranged on the top thereof, and a measurement circuit and a control circuit arranged inside thereof, wherein: the piezoelectric ultrasonic transducer array, the measurement circuit and the control circuit are connected in sequence.

3. The four-round-rod and double-half-ring combined three-dimensional calibration method for a single-point current meter according to claim 2 is characterized in that: The piezoelectric ultrasonic transducer array comprises: a support frame and four pairs of transducers arranged oppositely, wherein: each pair of transducers are arranged oppositely on the upper and lower sides of the support frame to form a measurement acoustic axis, and the four measurement acoustic axes have the same angle with the horizontal plane.

4. The four-round-rod and double-half-ring combined three-dimensional calibration method for a single-point current meter according to claim 1, characterized in that: Among the three groups of four positioning holes for positioning in the X, Y and Z directions, each group of positioning holes has an equal distance from the center of the flange and the four positioning holes in the same group are evenly distributed in the circumferential direction. The distances between the three groups of positioning holes and the center of the flange are different.

5. The four-round-rod and double-half-ring combined three-dimensional calibration method for a single-point current meter according to claim 1, characterized in that: The clamp is specifically a pair of semi-annular clamps, which are further provided with clamp liners to adapt to cylindrical instruments with different outer diameters.

6. The four-round-rod and double-half-ring combined three-dimensional calibration method for a single-point current meter according to any one of claims 1 to 5, characterized in that: include: Step 1: Connect the calibration device to the trailer through the top flange trailer positioning hole, and fully immerse the device below the water surface; Step 2: When calibrating in the X and Y directions, use the connecting rod to connect the two parts through the positioning holes on the outer ring of the flange and the positioning holes on the top of the two clamps: Use the connecting rod to assemble the flange and the clamp, place the electrical compartment of the current meter to be calibrated in the clamp of this device, set the projection of the support rod on the current meter transducer frame as the X-axis and the Y-axis, and set the central axis of the central fixing rod as the Z-axis; When installing the single-point current meter, ensure that the projection axis and the vertical direction of the flange positioning hole are in a straight line, so that the direction can be indicated through the positioning hole. When calibrating, the overall rotating device makes the corresponding positioning hole face forward, and the adjustment in the X and Y directions can be completed; Step 3: When calibrating in the Z direction, use the connecting rod to connect the two parts through the inner ring positioning hole of the flange and the side positioning holes of the two clamps: Use the connecting rod to assemble the flange and the clamp according to the Z direction positioning holes, place the electrical compartment of the current meter in the clamp of this device, and the Z axis of the central axis of the center fixing rod points straight ahead.

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