阅读说明：本技术 浮子质量流量计及计量方法 (Float mass flowmeter and metering method ) 是由 陈平 赵敉悦 陈明杰 于 2020-06-28 设计创作，主要内容包括：本发明属于仪器仪表、计量测量技术领域,尤其涉及一种浮子质量流量计及计量方法。本发明包括流量计管路和分别连接在流量计管路的上端口和下端口处的上法兰和下法兰,在流量计管路中设置有浮子,所述浮子设置在连接在流量计管路内的浮子档环上,仪表和线圈连接在流量计管路的外部。当流量不同时浮子的位置也发生变化,通过浮子流量计测量浮子的位置算出流量,实现高精度智能化处理,具备存储数据、查询数据等功能。本发明应用广泛,适合测量各种介质,不受外界温度的影响,具备产品结构简单、设计合理,使用方便、成本低、精确度高、具备数据远传功能的显著特点。其适用范围广、应用前景十分可观,具备较好的经济效益和社会效应。(The invention belongs to the technical field of instruments and meters and metering measurement, and particularly relates to a floater mass flowmeter and a metering method. The invention comprises a flowmeter pipeline, an upper flange and a lower flange which are respectively connected with an upper port and a lower port of the flowmeter pipeline, wherein a floater is arranged in the flowmeter pipeline and arranged on a floater blocking ring connected in the flowmeter pipeline, and an instrument and a coil are connected outside the flowmeter pipeline. When the flow is different, the position of the floater changes, the flow is calculated by measuring the position of the floater through the floater flow meter, high-precision intelligent processing is realized, and the intelligent flow meter has the functions of storing data, inquiring data and the like. The invention has wide application, is suitable for measuring various media, is not influenced by the external temperature, and has the remarkable characteristics of simple product structure, reasonable design, convenient use, low cost, high accuracy and data remote transmission function. The method has wide application range and very considerable application prospect, and has better economic benefit and social effect.)

1. Float mass flowmeter, including the flowmeter pipeline with connect respectively at the last flange and the lower flange of the last port of flowmeter pipeline and lower port department, characterized by: the flowmeter pipeline is internally provided with a floater, the floater is arranged on a floater blocking ring connected in the flowmeter pipeline, and the instrument and the coil are connected outside the flowmeter pipeline.

2. The float mass flow meter of claim 1, wherein: the fixed support is connected to the flowmeter pipeline, and the coil is connected to the flowmeter pipeline through the fixed support; the instrument is connected to the fixed support through a connecting screw.

3. The float mass flow meter of claim 1, wherein: the float stop ring is an opening expansion ring and is arranged below the flow meter pipeline by virtue of expansion force.

4. The float mass flow meter of claim 1, wherein: the inner wall of the pipeline is a cone-shaped body, and the diameter of the upper part of the pipeline is larger than that of the lower part of the pipeline.

5. The float mass flow meter of claim 1, wherein: the display panel in the instrument is connected with the input and output port of the mainboard CPU, the input end of the signal output is connected with the output port of the mainboard CPU, and the output end of the signal output is connected to the user equipment; the output end of the pulse output is connected with the coil, the input end of the pulse output is connected with the output end of the microprocessor of the mainboard CPU, the input end of the sampling module is connected with the coil, and the output end of the sampling module is connected with the input end of the mainboard CPU.

6. The float mass flow meter of claim 1, wherein: the coil is connected to the pulse output, the mainboard CPU sends a pulse with a given pulse width to the coil, and after the sending is finished, the connecting end of the coil is switched to the connection sampling module under the control of the mainboard CPU for the mainboard CPU to sample and analyze; the mainboard CPU finally transmits the analysis result to the display panel, the related content of the flowmeter is displayed through the display panel, and the related content of the flowmeter is transmitted to the signal output through the mainboard CPU for use by a user.

7. The metering method of the float mass flowmeter is characterized in that: the method comprises the following steps:

step 1, frequency domain analysis;

step 2, time domain analysis;

and 3, analyzing the quality and the frequency.

8. The method of claim 7, wherein: in the frequency domain analysis, when the calculation corresponding to the larger flow rate is carried out, the coil receives the pulse sent by the pulse output to generate an electromagnetic field, and when the coil sends the pulse with a certain width, the action of the electromagnetic field is exerted, so that the position of the floater in the pipeline of the flowmeter is also changed and sunk under the condition of different flow rates or flow rates; after the pulse is finished, the floater returns to the original balance position under the action of restoring force, and the coil induces the magnetic floater to generate electromagnetic induction current in the process of restoring the floater, and the electromagnetic induction current is supplied to the sampling module and is sent to the main board for data processing after being amplified and shaped;

the distance between the floater and the coil is smaller due to the larger flow in the pipeline of the flowmeter, the moving distance of the floater from the high-flow liquid level surface at the balance position to the stressed sinking position of the floater is larger under the action of the magnetic field force generated by the pulse in the coil, and when the pulse in the coil is finished, the moving time of the floater from the stressed sinking position of the floater to the high-flow liquid level surface at the balance position is longer;

because the flow in the pipeline of the flowmeter is smaller, the distance between the floater and the coil is larger, and the moving distance of the floater facing to the stressed sinking position of the floater at the small flow liquid level at the balance position is smaller under the action of the magnetic field force generated by the pulse in the coil; when the pulse in the coil is finished, the moving time of the floater floating from the stressed sinking position of the floater to the small-flow liquid level surface of the balance position is short;

when a pulse with a certain pulse width is given in the coil, the mass flow value can be obtained through calculation due to the fact that different floaters of flow need different time for returning to the original balance position under the action of restoring force;

according to lenz's law: the induced current has a direction in which the magnetic field of the induced current always hinders the change of the magnetic flux causing the induced current, and the polarity (direction) of the pulse current applied to the coil must be such that the electromagnetic force generated by the coil causes the float to move downward;

according to an electromagnetic force (ampere force) calculation formula: the acting force of the electrified lead in the magnetic field is equal to the length of the lead multiplied by the current passing through the lead multiplied by the magnetic field intensity;

F_d＝I*L*B (1)

in formula (1): i is the current in the coil, L is the length of the wire of the coil, and B is the field strength generated by the coil; f_dIs electromagnetic force;

in formula (2): f_fThe oscillation frequency of the floater under the pulse force, Tm is the pulse width time, and Tf is the time for the floater to return to the original balance position after the pulse is finished;

the following equations (1) and (2) show: f_dInversely proportional to the distance of the float from the coil, i.e. F_fIs proportional to F_dIt follows that Ff is inversely proportional to the flow rate of the flow meter line, as shown in the following equation:

in formula (3): v is the flow velocity, and Kv is the correction coefficient;

the conclusion of the frequency domain analysis is: electromagnetic force F generated by float receiving coil_dWhile oscillating at a frequency F_fInversely proportional to the flow velocity V in the pipe, with a correction factor K_vAs shown in equation (3).

9. The method of claim 7, wherein: the time domain analysis, when the flow or velocity of the tapered flowmeter pipeline increases, makes the float reach the equilibrium in the suitable damming area, at this moment will have:

Wf＝Vf(ρ_f-ρ)g (4)

in formula (4): wf is the displayed weight of the float, Vf is the volume of the float, ρ_f: is the density of the float, rho is the density of the medium, g is the acceleration of gravity;

because of the restoring force that receives for the float returns original equilibrium position, knows: the work done by the restoring force is equal to the potential energy of the float floating up to the equilibrium position:

F＝mgh*h/h＝Km*mgV²/h (5)

in the formula: h is the distance from the force sinking position of the floater to the balance position of the floater, V is the medium flow rate in the pipeline of the flowmeter, and the medium flow rate is in direct proportion to the distance h from the floater to the original balance position, namely V²＝Km*h²Km is a proportionality coefficient;

and m ═ ρ ═ Vf ═ ρ ═ Sf ═ L

In the formula: sf is the maximum sectional area of the floater, L is the same length of the floater, and a correction coefficient K is added to obtain the following formula:

and because:

qm＝ρf*qv

in the above formula: qm is mass flow, ρ f is float density, and qv is volume flow;

qm＝Ke*h (6)

in formula (6): ke is a correction coefficient, and h is the moving distance of the floater;

obtaining: qm ≧ h, i.e., the mass flow qm is proportional to the distance h that the float moves.

10. The method of claim 7, wherein: the quality and frequency analysis:

according to the fourier transform:

in the formula: a. b is the measuring range of the flowmeter, and f is the frequency value corresponding to the restoring force response time under the given pulse width;

from the analysis and derivation of formula (1) to formula (7):

qm＝Re*Kn*Ft (8)

in equation (8): qm is mass flow, Re is Reynolds coefficient, and Kn is correction coefficient;

ft: is the oscillation frequency of the float;

the following can be obtained: the oscillation frequency is in direct proportion to the mass flow.

Technical Field

The invention belongs to the technical field of instruments and meters and metering measurement, and particularly relates to a floater mass flowmeter and a metering method.

Technical Field

In the era of rapid development of science and technology, the demand of intelligent instruments is more and more obviously shown, and old instruments with lower precision are gradually replaced. Particularly in the field of flow measurement, the structure and algorithm of the metal rotor flow meter restrict the improvement of the precision, and the metal rotor flow meter has no remote transmission function or can not meet the requirements of users, and also restricts the development of the meter. Although the mass flowmeter has certain measurement accuracy, the development and market prospect of the mass flowmeter are also restricted due to high cost. Other flow meters also have such or other drawbacks or disadvantages as harsh media requirements, low accuracy, poor stability, etc.

Disclosure of Invention

Aiming at the defects and the improvement requirement in the prior art, the invention provides a floater mass flowmeter and a metering method. The float mass flowmeter and the metering method have the advantages of low price, low cost, wide applicability and high precision of the mass flowmeter.

The invention is realized by the following technical scheme:

the float mass flowmeter comprises a flowmeter pipeline, an upper flange and a lower flange, wherein the upper flange and the lower flange are respectively connected to an upper port and a lower port of the flowmeter pipeline; a float is arranged in the flow meter pipeline, the float is arranged on a float stop ring connected in the flow meter pipeline, and the meter and the coil are connected to the outside of the flow meter pipeline.

The fixed support is connected to the flowmeter pipeline, and the coil is connected to the flowmeter pipeline through the fixed support; the instrument is connected to the fixed support through a connecting screw.

The float stop ring is an opening expansion ring and is arranged below the flow meter pipeline by virtue of expansion force.

The inner wall of the pipeline is a cone-shaped body, and the diameter of the upper part of the pipeline is larger than that of the lower part of the pipeline.

The display panel in the instrument is connected with the input and output port of the mainboard CPU, the input end of the signal output is connected with the output port of the mainboard CPU, and the output end of the signal output is connected to the user equipment; the output end of the pulse output is connected with the coil, the input end of the pulse output is connected with the output end of the microprocessor of the mainboard CPU, the input end of the sampling module is connected with the coil, and the output end of the sampling module is connected with the input end of the mainboard CPU.

The coil is connected to the pulse output, the mainboard CPU sends a pulse with a given pulse width to the coil, and after the sending is finished, the connecting end of the coil is switched to the connection sampling module under the control of the mainboard CPU for the mainboard CPU to sample and analyze; the mainboard CPU finally transmits the analysis result to the display panel, the related content of the flowmeter is displayed through the display panel, and the related content of the flowmeter is transmitted to the signal output through the mainboard CPU for use by a user.

The metering method of the float mass flowmeter comprises the following steps:

step 1, frequency domain analysis;

step 2, time domain analysis;

and 3, analyzing the quality and the frequency.

In the frequency domain analysis, when the calculation corresponding to the larger flow rate is carried out, the coil receives the pulse sent by the pulse output to generate an electromagnetic field, and when the coil sends the pulse with a certain width, the action of the electromagnetic field is exerted, so that the position of the floater in the pipeline of the flowmeter is also changed and sunk under the condition of different flow rates or flow rates; after the pulse is finished, the floater returns to the original balance position under the action of restoring force, and the coil induces the magnetic floater to generate electromagnetic induction current in the process of restoring the floater, and the electromagnetic induction current is supplied to the sampling module and is sent to the main board for data processing after being amplified and shaped;

the distance between the floater and the coil is smaller due to the larger flow in the pipeline of the flowmeter, the moving distance of the floater from the high-flow liquid level surface at the balance position to the stressed sinking position of the floater is larger under the action of the magnetic field force generated by the pulse in the coil, and when the pulse in the coil is finished, the moving time of the floater from the stressed sinking position of the floater to the high-flow liquid level surface at the balance position is longer;

because the flow in the pipeline of the flowmeter is smaller, the distance between the floater and the coil is larger, and the moving distance of the floater facing to the stressed sinking position of the floater at the small flow liquid level at the balance position is smaller under the action of the magnetic field force generated by the pulse in the coil; when the pulse in the coil is finished, the moving time of the floater floating from the stressed sinking position of the floater to the small-flow liquid level surface of the balance position is short;

when a pulse with a certain pulse width is given in the coil, the mass flow value can be obtained through calculation due to the fact that different floaters of flow need different time for returning to the original balance position under the action of restoring force;

according to lenz's law: the induced current has a direction in which the magnetic field of the induced current always hinders the change of the magnetic flux causing the induced current, and the polarity (direction) of the pulse current applied to the coil must be such that the electromagnetic force generated by the coil causes the float to move downward;

according to an electromagnetic force (ampere force) calculation formula: the acting force of the electrified lead in the magnetic field is equal to the length of the lead multiplied by the current passing through the lead multiplied by the magnetic field intensity;

F_d＝I*L*B (1)

in formula (1): i is the current in the coil, L is the length of the wire of the coil, and B is the field strength generated by the coil; f_dIs electromagnetic force;

in formula (2): f_fThe oscillation frequency of the floater under the pulse force, Tm is the pulse width time, and Tf is the time for the floater to return to the original balance position after the pulse is finished;

the following equations (1) and (2) show: f_dInversely proportional to the distance of the float from the coil, i.e. F_fIs proportional to F_dIt follows that Ff is inversely proportional to the flow rate of the flow meter line, as shown in the following equation:

in formula (3): v is the flow velocity, and Kv is the correction coefficient;

the conclusion of the frequency domain analysis is: electromagnetic force F generated by float receiving coil_dWhile oscillating at a frequency F_fInversely proportional to the flow velocity V in the pipe, with a correction factor K_vAs shown in equation (3).

The time domain analysis, when the flow or velocity of the tapered flowmeter pipeline increases, makes the float reach the equilibrium in the suitable damming area, at this moment will have:

Wf＝Vf(ρ_f-ρ)g (4)

in formula (4): wf is the displayed weight of the float, Vf is the volume of the float, ρ_f: is the density of the float, rho is the density of the medium, g is the acceleration of gravity;

because of the restoring force that receives for the float returns original equilibrium position, knows: the work done by the restoring force is equal to the potential energy of the float floating up to the equilibrium position:

F＝mgh*h/h＝Km*mgV²/h (5)

in the formula: h is the distance from the force sinking position of the floater to the balance position of the floater, V is the medium flow rate in the pipeline of the flowmeter, and the medium flow rate is in direct proportion to the distance h from the floater to the original balance position, namely V²＝Km*h²Km is a proportionality coefficient;

and m ═ ρ ═ Vf ═ ρ ═ Sf ═ L

In the formula: sf is the maximum sectional area of the floater, L is the same length of the floater, and a correction coefficient K is added to obtain the following formula:

and because:

qm＝ρf*qv

in the above formula: qm is mass flow, ρ f is float density, and qv is volume flow;

qm＝Ke*h (6)

in formula (6): ke is a correction coefficient, and h is the moving distance of the floater;

obtaining: qm ≧ h, i.e., the mass flow qm is proportional to the distance h that the float moves.

The quality and frequency analysis:

according to the fourier transform:

in the formula: a. b is the measuring range of the flowmeter, and f is the frequency value corresponding to the restoring force response time under the given pulse width;

from the analysis and derivation of formula (1) to formula (7):

qm＝Re*Kn*Ft (8)

in equation (8): qm is mass flow, Re is Reynolds coefficient, and Kn is correction coefficient;

ft: is the oscillation frequency of the float;

the following can be obtained: the oscillation frequency is in direct proportion to the mass flow.

The invention has the following advantages and beneficial effects:

the invention is based on the basic structure of float flowmeter, which adds a magnetic float in the measuring pipeline, and when the flow rate is different, the position of the float changes, and the float flowmeter calculates the flow rate by measuring the position of the float. The present invention adds a coil device outside the measuring pipeline, after a given pulse is sent, the balance position of the float under a certain flow rate can be moved downwards under the action of electromagnetic force produced by the coil, and after the pulse is finished, the float can be restored to original balance position under the action of restoring force, so that the restoring period under the action of restoring force can be calculated, and the correspondent mass flow rate can be calculated. Has the characteristics of simple structure, reasonable design and convenient use. The invention carries out sampling and operation through a novel microprocessor and can transmit the locally displayed flow and the accumulated flow to a remote device in a 4-20mA or RS485 mode, thereby realizing high-precision intelligent processing. The invention can also realize the functions of managing, storing and inquiring data and the like by a database of the data through system management.

The invention has wide application, is suitable for measuring various media and is not influenced by the external temperature, and the influence of the temperature is very small and can be ignored. The invention also has the advantages of low product cost, high precision, data remote transmission function and considerable application prospect. The method is more practical in the fields of industry, agriculture, petroleum industry, aviation industry, schools, scientific research, laboratories and the like, and has better economic benefit and social effect.

The float mass flowmeter fills the technical blank of the industry in China. The electromagnetic force generated by the coil causes the floater to generate oscillation with different frequencies under different flow rates, and the coil also induces electromagnetic induction current generated by the floater oscillation. The mass flow is theoretically deduced to be in direct proportion to the oscillating frequency of the floater, and the oscillating frequency of the floater 5 is not influenced by temperature.

The invention has the technical characteristics that:

1. the characteristics of the float flowmeter and the mass flowmeter are fused, and the respective advantages are taken to fill up the technical blank of the product in the industry in China.

2. The product precision of the method is higher by combining the fast Fourier FFT algorithm with Malab modeling.

3. The novel high-speed microprocessor is adopted, so that the operation speed is higher, and the data processing capacity is higher.

4. The invention utilizes the algorithm that different periodic functions of the floater under the action of restoring force to calculate the mass, and is innovative development and invention.

5. The invention is a new innovation and invention of adding a coil which is both a given output and a sampling input to the flowmeter pipeline.

6. The data is transmitted remotely by using 4-20mA or RS485, and the system management can be realized.

7. The reasonable modular design makes production, detection and maintenance more convenient.

8. The ultra-large measurement capability can better meet the application requirements of different occasions in the market.

9. The alarm function enables a user to set and monitor the operation state more effectively.

The invention has the individual characteristics that:

1. the restoring frequency of the float under the action of restoring force is obtained by measuring the restoring period of the original balance point under the action of the restoring force of the float by loading a pulse to a coil additionally arranged on a flowmeter pipeline. The coil in the structure is used as a sampling component for pulse modification output and detection of restoring force at the end of pulse. Such a design is a characteristic feature in principle. The unique structure is also a personalized architecture from the realization point of view.

2. A new approach of a new flowmeter quality algorithm is invented through the idea of Fast Fourier Transform (FFT) algorithm and Matlab modeling. The method for determining and calculating the flow rate through the position of the floater in the prior art is changed, a new scheme for calculating the mass of the floater flow meter is innovated and broken through, and a new process and new production for realizing the product are completed, which is also a great individual characteristic and a specific realization of the invention.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic electrical diagram of the present invention;

FIG. 3 is a schematic diagram of the present invention for calculating a large flow rate;

fig. 4 is a diagram for calculation of a small flow rate according to the present invention.

In the figure: the device comprises an upper flange 1, a meter 2, a coil 3, a flowmeter pipeline 4, a floater 5, a lower flange 6, a signal output 7, a display panel 8, a main board CPU9, a pulse output 10, a sampling module 11, a large-flow liquid level surface 12, a floater stress sinking position 13, a small-flow liquid level surface 14, a floater stress sinking position 15, a fixing support 16, a screw 17, a connecting screw 18 and a floater baffle ring 19.

Detailed Description

The invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. It is specifically intended that the following description be regarded as illustrative in nature and not as restrictive in any way, since it is intended to limit the disclosure to the precise form disclosed and illustrated.