How does a gas turbine flowmeter work?

1.How a gas turbine flowmeter works.

Gas turbine flowmeters use a turbine for measurement. It converts the flow rate to the speed of the turbine and then to the speed proportional to the flow rate.

electrical signals. This type of flow meter is used to detect instantaneous flow and total accumulated flow, and its output signal is a frequency, which is easy to digitize. The induction coil and permanent magnet are pictured.

together fixed on the housing. When ferromagnetic.

When the turbine blades pass through the magnet, the magnetic resistance of the magnetic circuit changes, resulting in an inductive signal. The signal is amplified and shaped by an amplifier and sent to a counter or frequency meter to display the total accumulated flow. At the same time, the pulse frequency is converted to frequency and voltage to indicate the instantaneous flow.

The rotational speed of the impeller is directly proportional to the flow rate, and the number of revolutions of the impeller is directly proportional to the total amount of flow. The output of the turbine flowmeter is a frequency-modulated signal, which not only improves the anti-interference of the detection circuit, but also simplifies the flow detection system. It has a turndown ratio of up to 10:

1. The accuracy is within . The time constant of a turbine flowmeter with low inertia and small size.

Up to seconds. 2.Gas turbine flowmeters are widely used in petroleum, organic liquids, inorganic fluids, liquefied gases, natural gases and cryogenic fluids.

A vortex flowmeter is a meter that uses the phenomenon of regular vortex stripping to measure the flow of fluids. When the Reynolds number reaches a certain value, two parallel columns of vortices will be generated in the downstream of the column, and the upper and lower vortices will be alternately generated, which is called "Karman vortex street".

LWGY turbine flowmeter is a new generation of turbine flowmeter with the characteristics of simple structure, lightweight, high precision, good reproducibility, sensitive response, easy installation, maintenance and use, etc., LWGY turbine flowmeter is widely used to measure stainless steel 1Cr18Ni9Ti, 2Cr13 and corundum Al2O3, cemented carbide does not corrode, and there are no impurities such as fibers and particles. For liquids with a kinematic viscosity of less than 5 10-6 m2 s at working temperature, for liquids with a kinematic viscosity greater than 5 10-6 m2 s, the flowmeter can be used after actual liquid calibration. If the LWGY turbine flowmeter is matched with a display instrument with special functions, it can also be used for quantitative control, excess alarm, etc., which is an ideal instrument for flow metering and energy saving.

The air flow drives the blades to rotate, and the blades rotate proportional to the flow rate, and the blades drive the transmission shaft to rotate, so that the meter head rotates, and then the mechanical reading also rotates, and there is a pulse output in the meter head, which can be connected to the secondary instrument.

Turbine flowmeters have a turbine that, when in use, is mounted in a fluid piping and is supported by bearings at both ends. When the fluid passes through the turbine, the fluid hits the turbine blades, driving the rotation of the turbine blades. The measuring instrument of the turbine flowmeter measures the flow indirectly through the angular velocity of the turbine blades, and the method used is that the angular velocity of the blades is proportional to the fluid velocity.

Its angular velocity is detected by a sensing coil mounted in the casing, which changes the magnetic flux of the sensing coil when the turbine blades cut the magnetic field lines generated by the permanent magnet inside the casing. The sensor coil sends the detected periodic change in magnetic flux signal to the amplifier of the measuring instrument, and amplifies and shapes the signal.

A pulse signal proportional to the flow velocity is generated, and the cumulative flow value is obtained and displayed by the unit conversion and flowmeter accumulation circuit. At the same time, the pulse signal is also fed into the frequency current conversion circuit, which converts the pulse signal into analog current flow, and then indicates the instantaneous flow value.

The working principle of the turbine flowmeter: when the measured fluid (liquid, gas) flows through the sensor of the turbine flowmeter, the impeller in the sensor hits the turbine blades with the help of the kinetic energy of the fluid (liquid, gas) and generates driving force on the turbine. The turbine rotates, and the speed of the turbine changes with the change of the flow rate, that is, the flow rate is large, and the speed of the turbine is also large, and the flow rate is small, that is, the turbine speed is also small, which is proportional.

The rotational speed of the turbine is measured by a sensing coil mounted outside the casing. When the turbine blades cut the magnetic field lines generated by the magnet in the housing, it causes a change in the magnetic flux period in the sensing coil. Then the speed of the turbine is converted into an electrical pulse of the corresponding frequency through the magnetoelectric conversion device, and after amplification by the preamplifier, the signal is amplified and adjusted to produce a pulse signal proportional to the flow rate.

It is fed into the display meter for measurement and display, and the instantaneous flow rate and cumulative flow can be calculated according to the number of pulses per unit time and the cumulative number of pulses.

The turbine flow meter works on the principle that within a certain flow range, the rotational speed of the turbine is directly proportional to the flow rate of the fluid. The fluid flow drives the turbine to rotate, and the speed of the turbine is converted into an electrical pulse, and the data is displayed on a quadratic meter to reflect the fluid flow velocity.

Strong anti-electromagnetic interference and anti-vibration ability.

Its structure and principle are simple and easy to use.

Virtually no pressure loss, saving power consumption.

As shown in the figure, the structure of the flow sensor of the runwheel is simplified, and it can be seen from the figure that when the measured liquid flows through the sensor, under the action of the fluid, the impeller rotates under the force, and its speed is proportional to the average flow rate of the pipeline, and the rotation of the impeller periodically changes the magnetoresistance value of the magnetoelectric converter. The magnetic flux in the detection coil changes periodically, generating a periodic induced potential, that is, an electrical pulse signal, which is amplified and sent to the display instrument for display. If you want to know more about it, you can consult Feizhuo Technology, thank you!

How turbines work.

There is a commonly used type of traffic.

Measuring instruments. It is used in the measurement and control system of petroleum, chemical industry, metallurgy, scientific research and other fields, and the product has the advantages of stable performance, flexible use and high reliability, that is, self-congested liquid turbine flow.

Gauges. Self-reliant.

Liquid turbine flow meter.

How does it work? Here's a brief introduction:

The working principle of the liquid turbine flowmeter: the fluid flows through the sensor housing, because the blades of the impeller have a certain angle with the flow direction, the impulse of the fluid makes the blades have a rotating torque, overcome.

Frictional moment. And.

Fluid resistance. After that the blade rotates, in.

Moment balancing. The rear rotation speed is stable, and under certain conditions, the rotation speed is directly proportional to the flow rate, due to the blades had.

Permeability. It's in.

Signal detectors.

by permanent. Magnet.

and coils) in a magnetic field, rotating blades.

Cut magnetic field lines.

Periodically changes the coil.

Magnetic flux. So that the two ends of the coil are induced.

Electrical impulses. signal, this signal is amplified and shaped by the amplifier to form a continuous one with a certain amplitude.

Rectangular pulses. waves, which can be transmitted far away.

Display gauges. Shows the instantaneous flow and cumulative amount of fluid.

Within a certain flow range, the pulse frequency.

f is proportional to the instantaneous flow rate q of the fluid flowing through the sensor, and the flow equation is: q=3600 f k; Where: f - pulse frequency [Hz]; k – the gauge coefficient of the sensor [1 m], given by the calibration sheet.

If the unit is [1 l], q=; q - the instantaneous flow rate of the fluid (under working condition) [m h]; 3600——

Conversion factor. The gauge coefficient of each sensor is filled in by the manufacturer in the verification certificate, k value.

When placed in the matching display meter, the instantaneous flow rate and cumulative total amount can be displayed. A turbine is placed in the center of the pipe, which causes a change in the magnetic flux in the sensing coil. Liquid turbine flowmeters are built with flow rates.

inversely proportional. The pulse of the flag signal, when the fluid.

Turning it upside down. Pipes when the turbine is torsional of the counterometer.

Angular velocity. It is inversely proportional to the fluid flow rate.

The gas turbine flowmeter is mainly used for the flow measurement of air, nitrogen, oxygen, hydrogen, biogas, natural gas, steam and other medium fluids in industrial pipelines, and is almost not affected by the parameters of fluid density, pressure, temperature, viscosity and other parameters when measuring the volume flow under working conditions. There are no moving mechanical parts, so it is highly reliable and requires little maintenance. The instrument parameters can be stable for a long time.

The gas vortex flowmeter uses a piezoelectric stress sensor with high reliability and can operate in the operating temperature range of -20 +250. There are analog standard signals, there are also digital pulse signal output, easy to use with computers and other digital systems, is a relatively advanced, ideal flow meter.

The pulse frequency signal output by the gas vortex flowmeter is not affected by the change of fluid physical properties and composition, that is, the instrument coefficient of the punched car is only related to the shape and size of the vortex and the pipe sock hole within a certain Reynolds number range. However, as a flowmeter, the mass flow rate needs to be detected in the mass balance and energy metering, and the output signal of the flowmeter should monitor the volume flow rate and fluid density at the same time, and the physical properties and components of the fluid still have a direct impact on the flow metering. The gas vortex flowmeter is a new type of flowmeter that measures the fluid flow rate of closed pipelines according to the principle of Kármán vortex.

Because of its good medium adaptability, it can directly measure the volume flow of steam, air, gas, water and liquid without temperature and pressure compensation, and is equipped with temperature and pressure sensors to measure the standard volume flow and mass flow, which is an ideal alternative to throttle flow meters.

In order to improve the high temperature resistance and vibration resistance of the gas, the gas vortex flowmeter can be used under the harsh working conditions of high temperature (350) and strong vibration (1g) due to its unique structure and material selection. In practical application, often the maximum flow rate is far lower than the upper limit value of the instrument, with the change of load, the minimum flow rate is often lower than the lower limit value of the instrument, the instrument does not work in its best working section, in order to solve this problem, usually adopt the flow rate of the measurement place by reducing the diameter at the measurement place, and select the instrument of smaller diameter to facilitate the measurement of the instrument, but this reducer mode must have a straight pipe section with a length of more than 15d between the reducer and the instrument for rectification, so that the processing and installation are inconvenient.

In order to be easy to use, the battery-powered local display gas vortex flowmeter adopts micro-power high-tech, and can run uninterrupted for more than one year by using lithium battery power supply, which saves the purchase and installation costs of cables and display meters, and can display instantaneous flow and cumulative flow on the spot. The temperature-compensated vortex flowmeter also has a temperature sensor that can directly measure the temperature of the saturated steam and calculate the pressure to display the mass flow rate of the saturated steam. The integrated type of temperature and pressure compensation is equipped with temperature and pressure sensors for gas flow measurement, which can directly measure the temperature and pressure of the gas medium, so as to display the standard volume flow rate of the gas.

A gas turbine flowmeter is a type of flow meter used to measure the flow rate of gases, which uses the speed at which the turbine rotates to calculate the gas flow. A turbine flowmeter typically consists of a spherical housing, a turbine, a counter, and a temperature sensor. When the gas slips into the turbine flow meter, it causes the turbine to rotate.

The rotational speed of the turbine increases as the flow rate of the gas increases. The counter measures the number of times the turbine has been rotated and converts it into a measure of gas flow. The temperature wheel macro sensor is used to measure the temperature of the tung code gas entering the turbine flow meter to help calibrate the flow measurement results.

It is commonly used to measure the flow of high-pressure gases and high-temperature gases, and is widely used in the industrial, oil and gas industry, etc.

The gas turbine flowmeter is a new type of flow measuring instrument. It has the advantages of high precision, simple structure, high trillions of pressure, wide measurement range, small size, light weight, small pressure loss, long life, simple operation and convenient maintenance.

When a triangular cylindrical vortex generator is set in the fluid, regular vortices are alternately generated from both sides of the vortex generator, which is called a Kármán vortex, as shown in the figure on the right, and the vortex columns are arranged asymmetrically downstream of the vortex generator.

Parameters and requirements.

Measuring medium: gases, liquids, vapors.

Connection: flange card mounting, flange type, plug-in type.

Caliber specifications: Flange card mounted calibers are 25, 32, 50, 80, 100

Flange connection diameters are available in 100, 150, 200

Flow measurement range Normal measurement flow velocity range Reynolds number; gas 5 50m s; Liquid.

Normal Measurement Flow Range The flow measurement range of liquids and gases is shown in Table 2; The vapor flow range is shown in Table 3

Measurement accuracy level.

Medium temperature to be measured: room temperature 25 100

High temperature 25 150 -25 250

Output Signal Impulse voltage output signal High level 8 10V low level.

The pulse duty cycle is about 50%, and the transmission distance is 100m

Pulse current remote signal 4 20 mA, transmission distance of 1000m

Instrument operating environment Temperature: -25 +55 Humidity: 5 90% rh50

Material: Stainless steel, aluminum alloy.

Power supply: DC24V or lithium battery.

Explosion-proof grade: intrinsically safe IAIIBT3-T6

The IP65 vortex flow meter is a volumetric flow meter that measures the volumetric flow rate of gases, vapours or liquids, the volumetric flow rate under standard conditions or the mass flow rate according to the Karman vortex principle. It can also be used as a flow transmitter in an automated control system.

The instrument adopts advanced differential technology, with isolation, shielding, filtering and other measures, to overcome the problems of poor seismic resistance and small signal data disorder of similar products, and adopts unique sensor packaging technology and protective measures to ensure the reliability of the product. There are two types of products: basic type and composite type, the basic type measures a single flow signal; The combined type can measure temperature, pressure, and flow at the same time. Each type has a monolithic, split structure to adapt to different installation environments.

The measurement principle of vortex flowmeter saturated steam flow measurement In the 80s, people generally used standard orifice flowmeter, but from the perspective of the development of flow meter, although the orifice flowmeter has a long history and a wide range of applications; It is also the most fully studied, and the test data is the most complete, but there are still some shortcomings in measuring the saturated steam flow rate with a standard orifice flowmeter: first, the pressure loss is large; Second, the impulse pipe, the three groups and the connecting joints are easy to leak; Third, the range is small, generally 3 to 1, which is easy to cause low measurement value due to large fluctuations in flow. The vortex flowmeter has a simple structure, and the vortex transmitter is directly installed on the pipeline, which overcomes the leakage phenomenon of the pipeline.

In addition, the pressure loss of the vortex flowmeter is small, the range is wide, and the measurement range ratio of saturated steam can reach 30 to 1. Therefore, with the maturity of vortex flowmeter measurement technology, the use of vortex flowmeter is more and more favored by people.