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The vortex flow meter is a new type of flow meter developed based on the Karman vortex street principle. Vortex flowmeters are suitable for measuring the mass flow rate and volume flow rate of superheated steam, saturated steam, compressed air, general gases, water, and low-corrosivity liquids. How can we ensure the measurement accuracy of vortex flowmeters during installation? The following explains: 1. Vortex flowmeters are calibrated individually before leaving the factory. Since the discharge coefficient is calculated by software, the computed value is ultimately only an approximation, and there are still certain differences compared to the actual field conditions. Therefore, to ensure measurement accuracy, it is recommended to perform on-site calibration for each flowmeter, compare the calibrated discharge coefficient with the calculated value, determine the difference, and make adjustments accordingly. 2. Modification of the Reynolds number: There is a definite relationship between the flow coefficient of a vortex flow meter and the Reynolds number. When the mass flow rate changes, the Reynolds number changes in inverse proportion, which in turn causes a change in the flow coefficient. 3. The effect of temperature on vortex flowmeters and methods to address it: Changes in fluid temperature lead to changes in density, which in turn alters the relationship between differential pressure and flow rate. Additionally, temperature changes affect the inner diameter of the pipe as well as the size of the orifice. To counteract the effects of temperature changes, temperature sensors are used to measure the actual temperature at the site, and the data is sent to secondary instruments in order to correct the errors caused by these temperature changes. 4. Contractibility proofreading. When using a vortex flow meter to measure steam and gas flow rates, it is necessary to perform a correction for the compressibility of the fluid; the detailed correction coefficients can be found in the throttle installation design manual. 5. Calculation of the mass flow rate of steam: When using a vortex flow meter to measure steam, the flow rate is first determined from the differential pressure signal; thereafter, the density is obtained by referring to tables based on the steam’s temperature and pressure values, so as to calculate the mass flow rate of the steam.