LU series gas vortex flowmeter is mainly used for flow measurement of steam medium fluid in industrial pipelines. It is characterized by small pressure loss, large range of measurement and high accuracy. When measuring volume flow in working conditions, it is almost unaffected by fluid density, pressure, temperature, viscosity and other parameters. No moving mechanical parts, so high reliability, small maintenance. Instrument parameters can be stable for a long time. The gas vortex flowmeter adopts piezoelectric stress sensor with high reliability and can operate in the operating temperature range of -20℃ ~ +250℃. There are analog standard signal, but also digital pulse signal output, easy to use with computer and other digital systems, is a more advanced, ideal flow meter. A triangular column vortex generator is set up in the steam fluid, and regular vortexes are generated alternately from both sides of the vortex generator. Such vortexes are called karman vortexes. As shown in the figure on the right, the vortex columns are arranged asymmetrically in the downstream of the vortex generator. Assuming that the occurrence frequency of the vortex is f, the average velocity of the measured medium is, the width of the inlet surface of the vortex generator is d, and the surface diameter of the vortex generator is d, the following relationship can be obtained: f=SrU1/d=SrU/md, U1-- the average velocity of both sides of the vortex generator, m/s; Sr-- strouhal number; M -- ratio of the bow area on both sides of the vortex generating body to the cross section area of the pipeline

The volume flow in the pipeline qv is qv= D2U/4= D2mdf/4Sr K=f/qv=[D2md/4Sr]-1 -- the meter coefficient of the flowmeter, the number of pulses /m3 (P/m3). K is related not only to the vortex generator and the pipe geometry size, but also to the strouhal number. Strouhal number is a dimensionless parameter, which is related to the shape and Reynolds number of the vortex generator. Figure 2 shows the relationship between the strouhal number of the cylindrical vortex generator and the Reynolds number of the pipeline. As can be seen from the figure, in the range of ReD=2×104 ~ 7×106, Sr can be regarded as a constant, which is the normal working range of the instrument. When measuring gas flow, the flowmeter formula of VSF is (4) qVn and qV in the relationship curve between strauhal number and Reynolds number -- respectively the volume flow under standard state (0oC or 20oC, 101.325kPa) and working condition (m3/h). Pn, P-- are the pressure under standard state and working condition, respectively, Pa; Tn, T-- are the thermodynamic temperature under standard state and working condition, K; Zn and Z-- are gas compressibility in standard state and working state respectively. It can be seen from the above equation that the pulse frequency signal output by VSF is not affected by the physical properties and component changes of the fluid, that is, the meter coefficient is only related to the shape and size of the vortex generator and pipeline within a certain Reynolds number range. However, as a flowmeter, mass flow rate should be detected in material balance and energy measurement. In this case, the output signal of the flowmeter should be simultaneously monitored for volume flow rate and fluid density. The physical properties and components of the fluid have a direct impact on the flow measurement. The gas vortex flowmeter is a new type of flowmeter which can measure the fluid flow in closed pipeline according to the principle of karman vortex. Because of its good medium adaptability, it can directly measure the volume flow of steam, air, gas, water and liquid under working conditions without temperature and pressure compensation. Equipped with temperature and pressure sensors, it can measure the volume flow and mass flow under standard conditions, making it an ideal substitute for throttling flowmeter. In order to improve the high temperature resistance and vibration resistance of the gas vortex flowmeter, our company has recently developed the LUG improved vortex flow sensor. Due to its special structure and material selection, the sensor can be used in the severe working conditions of high temperature (350℃) and strong vibration (≤1g). In practice, often large flow is far from the ceiling, as the change of load, small flow and to be lower than the lower limit value, meter does not work at it * * * better working segments, the solution to this problem, usually used in the measurement of reducing increase of flow velocity measurement, and select the * * * * * * * * * the instrument measuring instrument, but this way of variable diameter in variable diameter pipe between the instrument and straight pipe length is more than 15 d were rectifier, processing, installation is inconvenient. Developed by our company profile shape of circular arc LGZ variable diameter rectifier, a rectifier, improve the velocity and change the velocity distribution of multiple function, its structure size is small, just as the process pipe inner 1/3, and the vortex street flowmeter into an organic whole, not only does not need to be added a straight pipe, and can also reduce the requirement for process straight section of pipe installation is very convenient. In order to use conveniently, the battery-powered local display gas vortex flowmeter adopts the high-tech of micro-power consumption, and USES lithium battery power to run continuously for more than one year, which saves the cost of cable and display instrument procurement and installation, and can display instantaneous flow, accumulated flow, etc. The temperature compensation vortex flowmeter also has a temperature sensor that can directly measure the temperature of saturated steam and calculate the pressure, thus showing the mass flow of saturated steam. The temperature-pressure compensation system is equipped with temperature and pressure sensors for gas flow measurement, which can directly measure the temperature and pressure of the gas medium, thus showing the standard volume flow of the gas. ◆ measuring medium: gas, liquid and steam; ◆ diameter: flange card-mounted caliber: choose 25,32,50,80,100; flange connection caliber: choose 100,150,200; flow measurement range: normal measurement flow rate range: Reynolds number: 1.5×104 ~ 4×106; Gas 5 ~ 50m/s; The measurement range of liquid and gas flow is shown in table 2. Steam flow range are shown in table 3 pieces measuring accuracy 1.0 magnitude 1.5 on the Richter scale temperature measured medium: normal temperature - pieces of 25 ℃ ~ 100 ℃ high temperature - 25 ℃ ~ 150 ℃ to 25 ℃ ~ 250 ℃ mixer output signal pulse voltage output signal high level 8 ~ 10 V low level from 0.7 V to 1.3 V pulse duty ratio is about 50%, far eastone signal transmission distance is 100 m impulse current 4 ~ 20 mA, transmission distance is 1000 m instrument using the environment temperature: 25 ℃ ~ + 55 ℃, humidity: 5 ~ 90% RH50 ℃ stainless material, Aluminum alloy ◆ power supply DC24V or lithium battery 3.6v ◆ explosion protection class iaiibt3-t6 ◆ protection class IP65

Gas vortex flowmeter product selection