Gas electrostatic vortex shedding flowmeter

Abstract

The invention belongs to the technical field of gas flow measurement, and discloses a gas electrostatic vortex shedding flowmeter. The flowmeter comprises a static electrode, a vortex street triangular prism, a measuring electrode, an auxiliary electrode and a shell, the shell is arranged in the horizontal direction in a penetrating mode, the static electrode, the vortex street triangular prism, the measuring electrode and the auxiliary electrode are all installed in the shell, and the static electrode, the vortex street triangular prism and the measuring electrode are sequentially connected in the horizontal direction. Measurement is carried out by using an electrostatic principle to replace a traditional method in which a piezoelectric sensor is used for measurement, so that the influence of interference such as vibration on the measurement precision is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of gas flow measurement, and in particular relates to a gas electrostatic vortex flowmeter. Background Art

[0002] Existing vortex flowmeters use piezoelectric sensors to measure the Kaman vortices formed behind the vortex generator. The piezoelectric sensor generates an electric charge that is output as a pulse signal through an amplifier. However, this also superimposes noise signals on the output, resulting in an extremely low signal-to-noise ratio for small signals. This makes it difficult for vortex flowmeters to measure small flow rates. Vibration near the measuring element can interfere with the signal output, causing the measured value to be inflated.

[0003] like Figure 2 As shown, in the prior art, a piezoelectric sensor 7 is arranged downstream of the vortex triangular column 2. The gas hits the vortex triangular column, forming alternating vortices downstream, and then the piezoelectric sensor swings under the influence of the vortex. The faster the flow rate, the more times the swing occurs per unit time. However, this technology has the disadvantage that when the vibration is large, the swing of the piezoelectric sensor is easily affected, and when the vibration frequency reaches the resonant frequency, the piezoelectric sensor loses its function.

[0004] Therefore, it is urgent to design a new type of gas electrostatic vortex flowmeter. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a gas electrostatic vortex flowmeter. It uses the electrostatic principle and high voltage to ionize the gas. The generated ions flow with the medium and hit the vortex generator to generate vortices. The charged vortices pass through the electrodes in turn, and the flow measurement is achieved by measuring the voltage changes of the electrodes, replacing the traditional method of using piezoelectric sensors for measurement, thereby reducing the impact of interference such as vibration on the measurement accuracy.

[0006] The technical solution adopted by the present invention to solve its technical problem is: The present invention provides a gas electrostatic vortex flowmeter, which includes an electrostatic electrode, a vortex triangular prism, a measuring electrode, an auxiliary electrode and a shell. The shell is arranged to penetrate the inside in the horizontal direction. The electrostatic electrode, the vortex triangular prism, the measuring electrode and the auxiliary electrode are all installed in the shell. The electrostatic electrode, the vortex triangular prism and the measuring electrode are connected in sequence in the horizontal direction. The auxiliary electrode is arranged perpendicular to the measuring electrode. The electrostatic electrode can discharge and release electrons into the gas. The vortex triangular prism can generate alternating vortices when the gas flows. The measuring electrode and the auxiliary electrode can measure the voltage of the gas. The measuring electrode and the auxiliary electrode are both provided with charge sensors.

[0007] Furthermore, the triangular tip of the vortex triangular prism is arranged in the same direction as the gas flow, the discharge end of the electrostatic electrode is arranged in the same direction as the gas flow, and the vortex triangular prism is arranged perpendicular to the measuring electrode.

[0008] Furthermore, the measuring upper plate and the measuring lower plate of the measuring electrode are arranged opposite to each other and are both insulated and fixed on the inner wall of the shell, and the auxiliary upper plate and the auxiliary lower plate of the auxiliary electrode are arranged opposite to each other and are both insulated and fixed on the inner wall of the shell.

[0009] Furthermore, the measuring electrode and the auxiliary electrode are common-mode suppression electrodes.

[0010] Furthermore, the device also includes an electrostatic amplifier, which is connected to the measuring electrode and the auxiliary electrode through a shaping circuit.

[0011] Furthermore, the electrostatic electrode of the device is a high-voltage electrostatic generator.

[0012] The advantages and positive effects achieved by the present invention are: 1. The present invention uses the principle of electrostatics. High voltage ionizes the gas. The generated ions flow with the medium and hit the vortex generator to generate vortices. The charged vortices pass through the common-mode suppression measurement electrodes in turn. The electrodes generate voltage changes, and output pulse signals through the electrostatic amplifier and shaping circuit, replacing the traditional method of using piezoelectric sensors for measurement. This reduces the impact of interference such as vibration on measurement accuracy. At the same time, the device has few overall components and a simple installation method, which makes the overall structure of the device simple and convenient for staff to disassemble and replace.

[0013] 2. The present invention has a higher signal-to-noise ratio. The common-mode suppression electrode eliminates vibration interference. The electrostatic charge generation circuit can be adjusted and automatically adjusted according to the output signal size, greatly expanding the lower limit of the flow rate. The range ratio can easily reach more than 1:50, which is greater than the 1:10 of the existing piezoelectric vortex street.

[0014] 3. This invention offers a long service life and no moving parts. As long as the insulation is operating normally, it should last for more than 20 years (if the triangular prism is not worn), allowing for continuous use. It also has extremely high seismic resistance and can be installed directly at the fan outlet. The signal is solely related to flow rate (velocity), has no resonant frequency, and is smooth with no peaks or valleys, making it easy to process. It also features simple sealing, can measure ultra-high pressure conditions, and the withstand voltage value is not affected by the sensor. Its simple structure, lacking any adjustment components, makes it suitable for production and can be directly manufactured on existing production lines. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A three-dimensional schematic diagram of a structural connection of the present invention; Figure 2 A three-dimensional schematic diagram of a structural connection in the prior art; Figure 3A schematic front view of a structural connection of the present invention; Figure 4 for Figure 3 A schematic side view of the connection structure; Figure 5 This is a voltage signal diagram when there is no flow in the present invention, where blue and green are the signals of the auxiliary electrode and the measuring electrode respectively, and yellow is the subtraction of the signals of the auxiliary electrode and the measuring electrode; Figure 6 : This is a voltage signal diagram when there is flow in the present invention, where the red line represents the enhanced signal, the blue line and the green line represent the signals of the auxiliary electrode and the measuring electrode respectively, and the purple box is the detection box; Figure 7 This is a photo of a real object of the present invention. DETAILED DESCRIPTION

[0016] The present invention will be further described in detail below with reference to specific examples. The following examples are merely illustrative and non-restrictive, and should not be used to limit the scope of protection of the present invention.

[0017] A gas electrostatic vortex flowmeter, such as Figure 1 and Figure 7 As shown, the flowmeter includes an electrostatic electrode 1, a vortex triangular prism 2, a measuring electrode 3, an auxiliary electrode 4 and a shell 5. The shell is arranged to pass through in the horizontal direction. The electrostatic electrode 1, the vortex triangular prism 2, the measuring electrode 3, and the auxiliary electrode 4 are all installed in the shell 5. The electrostatic electrode 1, the vortex triangular prism 2, and the measuring electrode 3 are arranged in sequence at intervals in the horizontal direction. The auxiliary electrode 4 is arranged perpendicular to the measuring electrode 3. The electrostatic electrode 1 can discharge and release electrons into the gas. The vortex triangular prism 2 can generate alternating vortices when the gas flows. The measuring electrode 3 and the auxiliary electrode 4 can measure the voltage of the gas. The measuring electrode 3 and the auxiliary electrode 4 are both provided with charge sensors.

[0018] like Figure 1 As described above, when in use, the gas flows horizontally through the inside of the housing, the electrostatic electrode 1 discharges, and the charge 6 generated by the discharge of the electrostatic electrode 1 flows with the gas. After the gas hits the vortex triangular column 2, an alternating vortex is generated downstream thereof. As the gas flows, at the measuring electrode 3, the electrons of the gas will hit the measuring electrode 3, causing the measuring electrode 3 to generate a voltage. The voltage of the measuring electrode 3 hitting the vortex reaches a maximum value. At the same time, since the auxiliary electrode 4 is perpendicular to the measuring electrode 3, the auxiliary electrode 4 and the generated vortex are perpendicular to almost no signal. ，Therefore, the vortex has little effect on the auxiliary electrode 4. The interference signal is added to the measuring electrode 3 and the auxiliary electrode 4 at the same time with the same phase, and can be filtered out by a simple subtraction circuit. Therefore, the voltage of the auxiliary electrode 4 is maintained within a certain stable threshold throughout the process. By analyzing the voltage changes of the measuring electrode 3 and the auxiliary electrode 4, the gas flow rate can be obtained.

[0019] In this embodiment, if Figure 3 and Figure 4 As shown, the triangular tip of the vortex triangular prism 2 is arranged in the same direction as the gas flow, so that the gas can impact the vortex triangular prism 2 and generate alternating vortices downstream thereof. The discharge end of the electrostatic electrode 1 is arranged in the same direction as the gas flow, so that the electrons generated by the discharge of the electrostatic electrode 1 can flow better with the gas. The vortex triangular prism 2 is arranged perpendicular to the measuring electrode 3, so that the electrons carried by the vortex have the greatest impact on the impact degree of the measuring electrode, thereby improving the measuring utility of the measuring electrode.

[0020] In this embodiment, if Figure 3 and Figure 4 As shown, the measuring upper plate 3-1 and the measuring lower plate 3-2 of the measuring electrode 3 are arranged opposite to each other and are both insulated and fixed on the inner wall of the shell, and the auxiliary upper plate 4-1 and the auxiliary lower plate 4-2 of the auxiliary electrode 4 are arranged opposite to each other and are both insulated and fixed on the inner wall of the shell, so as to reduce the blocking effect of the measuring electrode 3 and the auxiliary electrode 4 on the gas flow rate and improve the measurement accuracy.

[0021] Preferably, the measuring electrode 3 and the auxiliary electrode 4 are common-mode suppression electrodes to better eliminate vibration interference.

[0022] In this embodiment, the device further includes an electrostatic amplifier (not shown in the figure), which is connected to the measuring electrode 3 and the auxiliary electrode 4 via a shaping circuit; Using the principle of electrostatics, high voltage ionizes the gas. The resulting ions flow with the medium and strike the vortex generator, generating vortices. The charged vortices then pass through the common-mode suppression measurement electrodes, generating voltage changes that are then output as pulse signals via an electrostatic amplifier and shaping circuit. The device boasts a high signal-to-noise ratio. The common-mode suppression electrodes eliminate vibration interference, and the adjustable electrostatic charge generation circuit automatically adjusts based on the output signal, significantly extending the flow rate range. The range ratio easily reaches over 1:50, exceeding the 1:10 ratio of existing piezoelectric vortex generators.

[0023] In this embodiment, the device's electrostatic electrode 1 is a high-voltage electrostatic generator. A boost circuit generates an adjustable voltage of 1-3 kV, which automatically adjusts based on signal strength. Low signals generate a high voltage, resulting in a high ion concentration. This improves the signal at low flow rates, and the tip of the electrostatic electrode 1 easily ionizes to produce a large number of ions. High-concentration ions flow with the medium, alternating with vortices and striking the electrodes. The electrodes generate alternating signals, which are amplified by an amplifier circuit and output at a frequency corresponding to the flow rate (flow velocity), enabling flow measurement. The signal parallel to the triangular prism is the strongest, as the vortices are parallel to the prism. The signal perpendicular to the prism is the weakest, with virtually no vortices present. Therefore, the charge sensor can select the useful signal to shield the interference signal (the interference signal acts on both the measuring electrode 3 and the auxiliary electrode 4 sensors simultaneously, with the same phase, and can be eliminated by simple subtraction).

[0024] like Figure 5 and Figure 6 As shown, when there is no flow signal, the signals from the charge sensors of measuring electrode 3 and auxiliary electrode 4 are almost identical, with no output. This signal can be defined as an interference signal, which can be eliminated by simple subtraction. When there is flow, the signal obtained by subtracting the signals from the charge sensors of measuring electrode 3 and auxiliary electrode 4 is amplified to obtain an enhanced signal, eliminating the interference and leaving only the useful signal. Without this method, signal output in the inspection box would also cause interference.

[0025] Although the embodiments of the present invention are disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments.

Claims

1. A gas electrostatic vortex flowmeter, characterized in that: The flow meter comprises an electrostatic electrode (1), a vortex triangular prism (2), a measuring electrode (3), an auxiliary electrode (4) and a housing (5). The housing is provided with a through-hole arrangement in the horizontal direction. The electrostatic electrode (1), the vortex triangular prism (2), the measuring electrode (3) and the auxiliary electrode (4) are all installed in the housing (5). The electrostatic electrode (1), the vortex triangular prism (2) and the measuring electrode (3) are arranged in sequence and spaced apart in the horizontal direction. The auxiliary electrode (4) is arranged perpendicular to the measuring electrode (3). The electrostatic electrode (1) can discharge and release electrons into the gas. The vortex triangular prism (2) can cause the gas to generate alternating vortices when the gas flows. The measuring electrode (3) and the auxiliary electrode (4) can measure the voltage of the gas. The measuring electrode (3) and the auxiliary electrode (4) are both provided with charge sensors.

2. The flow meter according to claim 1, wherein: The triangular tip of the vortex triangular prism (2) is arranged in the same direction as the gas flow, the discharge end of the electrostatic electrode (1) is arranged in the same direction as the gas flow, and the vortex triangular prism (2) is arranged perpendicular to the measuring electrode (3).

3. The flow meter according to claim 2, wherein: The measuring upper electrode plate (3-1) and the measuring lower electrode plate (3-2) of the measuring electrode (3) are arranged opposite to each other and are both insulated and fixed on the inner wall of the shell; the auxiliary upper electrode plate (4-1) and the auxiliary lower electrode plate (4-2) of the auxiliary electrode (4) are arranged opposite to each other and are both insulated and fixed on the inner wall of the shell.

4. The flow meter according to claim 1, wherein: The measuring electrode (3) and the auxiliary electrode (4) are common-mode suppression electrodes.

5. The flow meter according to claim 1, wherein: The device also includes an electrostatic amplifier, which is connected to the measuring electrode (3) and the auxiliary electrode (4) via a shaping circuit.

6. The flow meter according to claim 1, wherein: The electrostatic electrode (1) is a high-voltage electrostatic generator.

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