Novel elastic sheet type optical fiber vortex shedding flowmeter

Abstract

A novel elastic sheet type optical fiber vortex shedding flowmeter comprises a pipe wall. The light source is fixedly connected to the outer wall of the pipe wall; the vortex generating body is arranged in the pipe wall and is used for generating a vortex street; the elastic sheet is fixedly connected to the middle of the vortex generating body; the optical fiber is attached to the middle of the elastic sheet for transmitting optical signals; the optical signal transmission channel bracket is arranged in the pipe wall; the optical signal transmission channel is fixedly connected to the middle part of the optical signal transmission channel bracket; and the signal processing table is fixedly connected to the outer wall of the pipe wall and is used for photoelectric signal conversion and identification. The device takes the optical fiber as a transmission medium, has stronger anti-electromagnetic interference capability and higher transmission rate and distance, can meet higher data transmission requirements, and has very high safety in various dangerous environments by using optical fiber sensing. The fluid directly acts on the elastic sheet sensing structure, original three-dimensional motion is converted into simple one-dimensional motion, collection and receiving of optical signals are facilitated, and the real-time performance of sensor detection is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of flow measurement, and more specifically, particularly to a novel elastic sheet type optical fiber vortex flowmeter. Background Art

[0002] The signal acquisition of traditional vortex flowmeters still uses the signal detection method of the previous electrical system. There is electromagnetic radiation in the measurement process, and its electromagnetic interference capability is relatively weak. It is not capable of performing accurate measurements in an environment with severe electromagnetic interference. It is extremely dangerous and cannot be used for the measurement of flammable and explosive gases. Utility Model Content

[0003] In order to overcome the above-mentioned shortcomings, the utility model aims to provide a novel elastic sheet type optical fiber vortex flowmeter, which can make an optical signal emitting element swing periodically with the movement of the fluid, so that the receiving element receives the periodic on-off optical signal, which is converted into a periodic electrical signal by the photoelectric conversion element. The signal frequency is obtained by analyzing the electrical signal, and then the fluid flow rate is obtained.

[0004] A novel elastic sheet type optical fiber vortex flowmeter comprises a pipe wall, a light source fixed to the outer wall of the pipe wall, a vortex generator arranged inside the pipe wall for generating a vortex, an elastic sheet fixed to the middle of the vortex generator, an optical fiber attached to the middle of the elastic sheet for transmitting an optical signal, an optical signal transmission channel bracket arranged inside the pipe wall, an optical signal transmission channel fixed to the middle of the optical signal transmission channel bracket, and a signal processing station fixed to the outer wall of the pipe wall for photoelectric signal conversion and identification.

[0005] Furthermore, the light source is fixedly connected to the top of the tube wall, and the signal processing station is fixedly connected to the top of the tube wall.

[0006] Furthermore, the optical fiber is signal-connected to the light source.

[0007] Furthermore, the optical signal transmission channel bracket is located behind the elastic sheet, and the optical signal transmission channel is signal-connected to the signal processing station.

[0008] Furthermore, the signal processing station includes a phototransistor, a constant voltage power supply and an oscilloscope, and the constant voltage power supply, the phototransistor and the oscilloscope are electrically connected.

[0009] Furthermore, the vortex generator is in the shape of a triangular prism.

[0010] Furthermore, the vortex generating body is cylindrical in shape.

[0011] Furthermore, the vortex generating body is in the shape of a cylinder with a slit.

[0012] Furthermore, the vortex generator is in a T-shape.

[0013] Compared with the prior art, the beneficial effects of the utility model are:

[0014] 1. This device uses optical fiber as the transmission medium, has a stronger ability to resist electromagnetic interference, can ensure the stability and reliability of data transmission, has a higher transmission rate and distance, can meet higher data transmission requirements, and makes optical fiber sensing very safe in a variety of dangerous environments.

[0015] 2. The fluid acts directly on the elastic sheet sensing structure, which improves the real-time performance of the sensor detection.

[0016] 3. Due to the mechanical properties of the elastic sheet's own structure, the pressure change of the flow field is converted into a one-dimensional swing of the elastic sheet, which is beneficial to the collection and reception of optical signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0018] Figure 1 It is a schematic diagram of the overall structure of a specific embodiment 1 of the optical fiber vortex flowmeter.

[0019] Figure 2 It is the logic block diagram of the signal processing station.

[0020] Figure 3 It is a schematic diagram of the overall structure of the second specific embodiment of the optical fiber vortex flowmeter.

[0021] Figure 4 It is a schematic diagram of the overall structure of the specific embodiment 3 of the optical fiber vortex flowmeter.

[0022] Figure 5 It is a schematic diagram of the overall structure of a fourth specific embodiment of the optical fiber vortex flowmeter.

[0023] In the figure: 1-tube wall, 2-light source, 3-vortex generator, 4-elastic sheet, 5-optical fiber, 6-optical signal transmission channel, 7-signal processing station, 71-phototransistor, 72-constant voltage power supply, 73-oscilloscope, 8-optical signal transmission channel bracket. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model. Specific embodiments

[0025] like Figure 1 , Figure 2As shown, a novel elastic sheet 4-type optical fiber 5 vortex flowmeter comprises: a pipe wall 1, which is a pipe wall 1 of a 20 mm transparent PVC pipe; a light source 2 fixedly connected to the outer wall of the pipe wall 1, the light signal output by the light source 2 adopts a wavelength range that can be detected by an oscilloscope 73, the light source 2 is fixedly connected to the top of the pipe wall 1, and the visible light outlet faces the inside of the pipe wall 1, the optical fiber 5 is signal-connected to the light source 2, and the light source 2 transmits the optical signal to the optical fiber 5; a vortex generator 3 arranged inside the pipe wall 1 to generate a vortex street, the vortex generator 3 is in the shape of a triangular prism, and due to the existence of fluid viscosity, when the fluid flows around the vortex generator 3, boundary layer separation will occur in its rear half to form a pair of symmetrical vortices with opposite rotation directions. As the fluid flow rate continues to increase, the pair of unstable symmetrical vortices will split and eventually form almost stable vortices that rotate in opposite directions and are alternately arranged; the elastic sheet 4 is fixedly connected to the middle part of the vortex generator 3, and the elastic sheet 4 is a thin sheet with a thickness of 0.01 mm. The elastic sheet 4 is rectangular in shape, and the fluid directly acts on the sensing structure of the elastic sheet 4, thereby improving the real-time performance of the sensor detection. Due to the mechanical properties of the elastic sheet 4's own structure, the pressure change of the flow field is converted into a one-dimensional swing of the elastic sheet 4, which is beneficial to the collection and reception of optical signals; an optical fiber 5 for transmitting optical signals, one end of the optical fiber 5 penetrates the pipe wall 1 and is inserted into the outlet of the light source 2, and the other end of the optical fiber 5 penetrates the vortex generator 3 and is attached to the middle of the elastic sheet 4, and its end face exceeds the free end of the elastic sheet 4. Using the optical fiber 5 as a transmission medium has a stronger anti-electromagnetic interference ability, can ensure the stability and reliability of data transmission, has a higher transmission rate and distance, can meet higher data transmission requirements, and makes the optical fiber 5 sensing have very high safety in various dangerous environments; an optical signal transmission channel bracket 8 arranged inside the pipe wall 1, located behind the optical fiber 5; an optical signal transmission channel 6 fixedly connected to the middle of the optical signal transmission channel bracket 8, one end of the optical signal transmission channel 6 is aligned with the optical fiber 5 to receive the optical signal, and the other end of the optical signal transmission channel 6 penetrates the pipe wall 1 and is connected to the signal of the signal processing station 7; a signal processing station 7 fixedly connected to the outer wall of the pipe wall 1 for photoelectric signal conversion and identification. The signal processing station 7 is fixed to the top of the tube wall 1. The signal processing station 7 includes a phototransistor 71, a constant voltage power supply 72 and an oscilloscope 73. The constant voltage power supply 72, the phototransistor 71 and the oscilloscope 73 are electrically connected. The optical signal output from the optical signal transmission channel 6 is converted into an electrical signal by the phototransistor 71. The signal frequency is obtained by analyzing the electrical signal. The frequency is consistent with the frequency of the swing of the optical fiber 5 attached to the middle of the elastic sheet 4 for transmitting the optical signal, and the vortex shedding frequency of the fluid is indirectly obtained, so that the fluid flow rate is calculated by the formula. Specific embodiments

[0026] like Figure 3As shown, what is different from the specific embodiment 1 is that the vortex generator 3 in this embodiment is cylindrical in shape. The cylindrical vortex generator 3 has the characteristic of simple shape, which makes its processing relatively easy and reduces the production cost. Moreover, the resistance coefficient generated by the cylindrical vortex generator in the fluid is relatively small, which helps to reduce the energy loss when the fluid passes through and improve the efficiency of flow measurement. Specific embodiments

[0027] like Figure 4 As shown, what is different from the specific embodiment 1 is that the vortex generator 3 in this embodiment is in the shape of a cylinder with a slit. The cylindrical vortex generator with a slit can effectively enhance the strength of the vortex signal through the blowing and suction effect of the slit, making the vortex separation more stable and the signal strength higher, thereby improving the accuracy and reliability of the flow measurement, and at the same time can also reduce the minimum measurable Reynolds number, which means that the flow measurement can be effectively carried out at a lower flow rate, expanding the measurement range, and improving the flexibility and adaptability of the measurement. Specific embodiments

[0028] like Figure 5 As shown, what is different from the specific embodiment 1 is that the vortex generator 3 in this embodiment is T-shaped. The T-shaped vortex generator has a strong vortex signal and a high signal-to-noise ratio, can generate a strong and clear vortex signal, improve the accuracy of flow measurement, and has a constant Strouhal number and good stability at different flow rates.

[0029] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions described in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A novel elastic sheet type optical fiber vortex flowmeter, comprising a pipe wall (1); a light source (2) fixedly connected to the outer wall of the pipe wall (1); a vortex generator (3) disposed inside the pipe wall (1) for generating a vortex; an elastic sheet (4) fixedly connected to the middle of the vortex generator (3); an optical fiber (5) attached to the middle of the elastic sheet (4) for transmitting an optical signal; an optical signal transmission channel bracket (8) disposed inside the pipe wall (1); an optical signal transmission channel (6) fixedly connected to the middle of the optical signal transmission channel bracket (8); and a signal processing station (7) fixedly connected to the outer wall of the pipe wall (1) for converting and identifying optical signals.

2. The novel elastic sheet optical fiber vortex flowmeter according to claim 1 is characterized in that: The light source (2) is fixedly connected to the top of the tube wall (1), and the signal processing station (7) is fixedly connected to the top of the tube wall (1).

3. The novel elastic sheet optical fiber vortex flowmeter according to claim 2 is characterized in that: The optical fiber (5) is signal-connected to the light source (2).

4. The novel elastic sheet optical fiber vortex flowmeter according to claim 3 is characterized in that: The optical signal transmission channel bracket (8) is located behind the elastic sheet (4), and the optical signal transmission channel (6) is signal-connected to the signal processing station (7).

5. The novel elastic sheet optical fiber vortex flowmeter according to claim 4 is characterized in that: The signal processing station (7) comprises a phototransistor (71), a constant voltage power supply (72) and an oscilloscope (73), and the constant voltage power supply (72), the phototransistor (71) and the oscilloscope (73) are electrically connected.

6. According to the novel elastic sheet optical fiber vortex flowmeter as claimed in claim 1, the vortex generating body (3) is in the shape of a triangular prism.

7. According to the novel elastic sheet type optical fiber vortex flowmeter as claimed in claim 1, the vortex generating body (3) is cylindrical in shape.

8. According to the novel elastic sheet optical fiber vortex flowmeter as claimed in claim 1, the vortex generating body (3) is in the shape of a cylinder with a slit.

9. According to the novel elastic sheet type optical fiber vortex flowmeter as claimed in claim 1, the shape of the vortex generator (3) is T-shaped.

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