Difference and introduction of vortex flowmeter and precession vortex flowmeter
AK-LUGB steam flow meter, liquid crystal integrated display instantaneous total flow, temperature and pressure compensation, accurate measurement, lithium battery 24V power supply, 4-20mA standard signal output, optional RS485 communication, split pulse output and other specifications , Manufacturer selection quotes! Reasonable price, reliable quality!
Vortex flowmeter principle:
  The boiler vortex flowmeter is composed of vortex attack bodies, detection probes and corresponding electronic circuits designed in the flow field. When the fluid flows through the vortex attack body, two sides of the vortex are formed on both sides of the vortex. This vortex is called the Karman vortex street. Based on Karman vortex street theory, Strohal proposed that the frequency of Karman vortex street is directly proportional to the velocity of the fluid and gives the relationship between frequency and velocity:
f = St × V/d 
Where: f vortex attack frequency (Hz)
Average velocity (m/s) on both sides of V vortex attack body
St. Strouhal coefficient (constant)
These alternating vortices form a series of alternating negative pressures, which act on the detection probe and generate a series of alternating electrical signals. After the preamplifier converts, shapes, and amplifies, the output and the vortex become synchronous. A proportional pulse frequency signal or standard signal.
Corrosion resistance, stable and reliable, long life, long-term operation without special maintenance; Mechatronics, the daily measurement process does not need to be on duty; In the process installation conditions are not harsh, the upper and lower sections of the instrument can be compared with orifice plate and vortex flowmeter It is greatly shortened; the measurement accuracy can meet the current trade measurement requirements (≤1.5%); the temperature and pressure compensation function is integrated in the body of the watch, and the standard volume flow or standard mass flow of the fluid can be measured. The use of fully intelligent, digital circuit design can automatically compensate for the measured fluid density or standard volume calculation. Lithium-ion battery-powered models can work continuously for more than two years without an external power supply.
Vortex Flowmeter Selection
The correct selection of argon flowmeter is a prerequisite for ensuring the use of a good vortex flowmeter. Important factors need to be considered: pass through ( DN ), installation method, medium temperature, output signal, media type
Precautions
Upstream and downstream of the flowmeter provides enough straight pipe sections and ensures a non-curved symmetrical profile. Install the valve downstream of the instrument whenever possible.
Vertical installation is usually the preferred choice. The upward-moving fluid ensures that the instrument is always full and the components in the medium are evenly distributed.
When installing in long pipelines that are prone to vibration, removers should be installed upstream and downstream of the flowmeter.
For gas applications, installation of the instrument should be avoided at the bottom of the U -bend to avoid the phenomenon of water hammer caused by the absorption of condensation during driving. The strength of the water hammer causes the sensing mechanism to exert excessive force, resulting in permanent damage to the sensor.
Vortex Flow Meter Overview:
The basic principle of the AK-LUGB vortex flowmeter is the principle of Karman vortex street, that is, the "vortex vortex separation frequency is proportional to the flow velocity." The diameter of the transmitter body is basically the same as the nominal diameter of the instrument. As shown in Figure 1, a cylindrical body with an approximately isosceles triangle is inserted into the flow body. The axis of the column is perpendicular to the flow direction of the measured medium, and the bottom surface faces the fluid.
When a non-streamlined vortex generator (baffle) is placed in the fluid, two rows of regular vortices are generated alternately from both sides of the vortex generator. This vortex is called a Karman vortex, as shown in Figure (a).
When the measured medium flows through the column, vortices are alternately generated on both sides of the column, and the vortexes are continuously generated and separated. In the downstream of the column, two columns of vortices, namely “vortex streetâ€, are formed in a staggered arrangement. Theoretical analysis and experiments have shown that the frequency of vortex separation is proportional to the velocity of the medium on the column side.
Swirl staggered separation generates pulsating pressure in the wakes on both sides of the column and behind the column. The detection probe located inside (or behind) the column is subjected to this tiny pulsating pressure, so that it is embedded in the probe. The piezoelectric crystal element is subjected to alternating stress to generate an alternating charge signal. The signal is converted and amplified by the charge on the amplifier, filtered and clipped, and the square wave voltage pulse signal with the same frequency as the vortex separation frequency is output. The signal is sent to the local display. Each pulse from the sensor will represent a certain volume of fluid under test. The total number of pulses output over a period of time will represent the total volume of fluid flowing through the sensor during this time. The sensor's output voltage pulse signal is sent to the integrated local display. The local display instrument adopts the latest micro-power CPU to measure the frequency signal output by the vortex sensor. According to the set density, the vortex flow coefficient performs flow calculation, and the on-site liquid crystal display instantaneous flow and total flow.
Vortex Flowmeter Product Advantage: Steam Flow Meter
â–² Vortex flowmeter is not affected by temperature and pressure, it is not easy to block, not easy to jam, not easy to scale, high temperature, high pressure.
â–² Vortex flowmeter is safe and explosion proof, suitable for harsh environments.
â–²The vortex flowmeter has no moving parts and no voids. The product is free of wear and dirt, and it requires no mechanical maintenance and has a long service life.
â–¡ Vortex flowmeter adopts micro-power high-tech, battery-powered on-site display flowmeter, which can run continuously for more than two years.
â–² vortex flowmeter compensation and integrated design.
â–²The current output of vortex flowmeters are all electrically isolated and have good common-mode interference suppression capabilities.
▲ Vortex flowmeters display both flow and cumulative flow values ​​without having to switch between them.
â–² Vortex flowmeter uses anti-vibration probes to effectively eliminate external vibration effects.
â–² Vortex flowmeter circuit surface mount technology, compact structure, high reliability.
â–² Vortex flowmeter uses a split-type signal converter with a cable length of up to 10 meters.
â–² The overall structure of the vortex flowmeter is well-designed, with a wide range of dynamic measurements and low pressure loss.
â–² vortex flowmeter vortex flowmeter split stainless steel, applicable to the measurement of corrosive media.
â–² vortex flowmeter on-site liquid crystal display, pulse, 4-20mA output or 485 communication, can be connected with industrial automation systems.
Vortex Flowmeter Instrument Installation Design
The correct installation of the meter is an important part of ensuring the normal operation of the meter. If it is improperly installed, it will affect the accuracy of the meter, and it will affect the service life of the meter and even damage the meter.
(I) Installation Environment Requirements:
1. Avoid strong electrical equipment, high frequency equipment, and strong switching power supplies as much as possible. The power supply of the instrument is separated from these devices as much as possible
Instrument selection is a very important task in instrument applications. The correctness of the instrument selection will directly affect the normal operation of the instrument. Therefore, when users and design organizations choose the company's products, please carefully read the information in this section, carefully check Fluid process parameters can be contacted at any time with our sales or technical support department to ensure correct selection.
Applicable flow range and determination of instrument caliberThe choice of instrument diameter is determined according to the flow range. The measuring range of different caliber vortex flowmeters is not the same. Even if the same caliber flow meter is used for different media, its measurement range is not the same. The actual measurable flow range needs to be determined by calculation.
(a) Flow range of air and water under vortex flowmeter reference conditions
1. Gas: normal temperature and pressure air, t=20°C, P=0.1 MPa (absolute pressure), Ï=1.205 kg/m3, Ï…=15×10-6 m2/s.
2. Liquid: normal temperature water, t=20°C, Ï=998.2 kg/m3, Ï…=1.006×10-6 m2/s.
(b) Basic steps for determining the flow range and instrument diameter for vortex flowmeters :
1. Clear the following operating parameters.
(1) Names and components of measured media
(2) Minimum, common, maximum flow of working conditions
(3) The lowest, common, highest pressure and temperature of the medium
(4) The viscosity of the medium under working conditions
Precession vortex flowmeter adopts imported chips, with one-piece compensation, high measurement accuracy, stable performance, price concessions, and high-quality after-sales service, allowing you to buy the rest assured, with the peace of mind!
First, intelligent precession vortex flowmeter overview:
AK-LUX type intelligent precession vortex gas flow meter adopts advanced micro-output technology. It has the advantages of strong function, wide flow range, simple operation and maintenance, and easy installation and use. The main technical indicators have reached the advanced level of similar foreign products. Can be widely used in petroleum, chemical, power, metallurgy, coal and other industries measuring various gases.
1 , Built-in pressure, temperature, flow sensor, high safety performance;
2. Using dual sensors, a novel signal processing amplifier and a unique filtering technology, effectively eliminating the interference signals generated by pressure fluctuations and pipeline vibrations, greatly improving the anti-jamming ability of the flowmeter, and making the small flow rate have excellent stability;
3 , range width ratio of up to 1:15 or more; minimum measurement of instantaneous flow rate of 0.03m3/min;
4 , Compact structure, no mechanical moving parts, sensor and display integration, beautiful appearance; factory has been in accordance with national standards and industry standards through a strict standard calibration equipment for parameter calibration, the user does not need to change the parameter settings;
5 , unique pressure, temperature sensor self-diagnosis function, and clear and concise display in the LCD screen and host computer interface;
6. With 485 communication interface, it can remotely transmit the measured parameters such as temperature, pressure, instantaneous flow, standard volume and other parameters of the measured medium, and the transmission distance is ≤ 1.2km .
7. Frequency analog signal output (200~1000Hz) with flow, pressure and temperature, transmission distance is 2km;
8. Small throttling, low requirements for environmental conditions, low installation requirements for front and rear straight pipe sections of the flowmeter (before ≥ 3DN, after ≥ 1DN), accurate measurement for horizontal or inclined installation; installation and use of the flowmeter And maintenance is particularly convenient;
9 , the flow meter has a built-in set of nickel-metal hydride batteries, in the case of no external power supply can be used continuously for 1 to 3 years;
10 , intelligent flow totalizer can be positioned at any angle (rotation angle of about 350 °), making the meter more convenient and direct reading under various installation conditions;
11. Unique time display and real-time data storage functions ensure that internal data will not be lost in any situation;
12 , complete specifications, from DN25 ~ DN200, to meet the user's needs of various diameters and flow;
13 , the instrument has explosion-proof and protective functions, explosion-proof signs ExibI, protection class IP55.
Second , intelligent precession vortex flowmeter selection:
When the flowmeter is used to measure gas, first, according to the pipeline gas volume and the temperature and pressure range that the medium may reach, the maximum and minimum volumetric flow rates under working conditions are estimated, and the flowmeter specifications are properly selected; if both calibers can cover the flow rate Range, with the pressure range allowed, it is recommended to select a smaller size flow meter. In order to facilitate maintenance without affecting the fluid transport, it is recommended to install a bypass pipe and ensure the length of the straight pipe section. If the gas contains large particles or fibers, a filter should be installed upstream.
The flow meter works:
When the fluid in the axial direction enters the inlet of the flow sensor, it is forced to rotate around the centerline under the action of the vortex generator to generate a vortex flow. The vortex flow swirls in the Venturi tube and reaches the constricted section after sudden throttling. The eddy currents are accelerated and the center of the vortex precesses along a conical helix as it passes through the diffusion section. At this time, the eddy current precession frequency signal detected by the two piezoelectric sensors is amplified, filtered, and shaped by the pre-circuit, converted into two pulse signals proportional to the flow velocity, and processed by the processing circuit in the integrator. Comparing and judging, and rejecting the interference signal, send it to the intelligent flow totalizer together with the signal detected by the temperature and pressure sensor, perform calculation and processing, and display the volume flow and the total amount of the fluid directly on the LCD screen.
Third , the main characteristics of intelligent precession vortex flowmeter :
1. No mechanical moving parts, corrosion resistance, stable and reliable, long life, no special maintenance for long-term operation;
2. Adopt 16-bit computer chip, high integration, small size, good performance, strong machine function;
3. The intelligent flowmeter integrates flow probes, microprocessors, pressure sensors and temperature sensors. It adopts a built-in combination to make the structure more compact. It can directly measure the flow, pressure and temperature of the fluid and automatically track the compensation and compression factors in real time. Correction;
4. The use of dual detection technology can effectively improve the detection signal strength and suppress the interference caused by the pipeline vibration;
5. The use of Chinese character dot-matrix display, displaying multiple digits, intuitive and convenient reading, can directly display the volume flow under the working state, the volume flow under the standard state, the total amount, and the medium pressure, temperature and other parameters;
6. Using EEPROM technology, convenient parameter setting, can be permanently saved, and can save up to one year of historical data;
7. Converter can output frequency pulse, 4-20mA analog signal, and has RS485 interface and HART protocol, can be directly connected with the computer, transmission distance up to 1.2Km;
8. With the company's FM data collector, remote data transmission can be performed via the Internet or telephone network;
9. The pressure and temperature signals are the transmitter input mode, and the interchangeability is strong;
10. The whole machine. Low power consumption, internal battery power supply, or external power supply.
Intelligent precession vortex flowmeter production workshop:
Tank Top Heater,Gas Heater,Radiant Heater,Heater For Tank Heater
Chant Heat Energy Science & Technology (Zhongshan) Co.,Ltd. , https://www.chantgasappliance.com