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When using vortex flowmeters to measure compressed air, the measurement results may be affected by various factors due to an inappropriate choice of flowmeter or the measurement environment. So, what aspects should we pay attention to in order to ensure more accurate measurement results? 1. Minimum flow rate problem: The amplitude of the vortex street signal is proportional to the square of the flow velocity and the density of the fluid being measured. In other words, when the detection sensitivity of the vortex flow meter remains constant, an increase in the operating pressure of the fluid and a rise in its density can result in a slight decrease in the measured flow velocity. Conversely, at a certain flow velocity, if the operating pressure of the fluid increases and its density rises, the amplitude of the vortex signal also increases, allowing the detection sensitivity to be reduced. For gases at atmospheric pressure, the lower flow velocity limit for vortex flow meters can reach 4–5 m/s. For pressurized gases, such as compressed air, the lower flow velocity decreases due to the increased density. Therefore, when selecting a model, the actual operating flow rate must be taken into account. 2. Vibration effects: Compressed air is generated by air compressors or high-pressure fans. When these devices are in operation, they experience vibration to varying degrees, and sometimes the vibration is quite intense; this vibration is transmitted through the connecting pipes. When selecting and determining the location of vortex flowmeters, this influencing factor must be taken into full consideration. Among the various detection methods, the vibration resistance of the instruments varies depending on the type of sensing element used. For the vortex street type sensing element, the vibration resistance can reach 0.5–1G. When determining the installation location of a vortex flow meter, it should be placed as far away as possible from power equipment such as air compressors and fans. 3. Pulsating flow effects: The gas output by fans and compressors often contains a certain degree of pulsation. The pulsation frequency and amplitude of the gas output by a Roots blower are related to the speed of the rotor gears and the constant displacement volume; typically, the pulsation frequency ranges from 100 to 200 Hz ； In contrast, reciprocating compressors have a lower frequency of gas output, usually just a few hertz. Furthermore, some gas-powered equipment, such as air hammers and pneumatic tools, can also cause pulsations in the air flow, with both the frequency and amplitude of these pulsations being random. When using vortex flowmeters to measure compressed air, the issues mentioned above such as the minimum flow rate, vibration, and pulsating flow can all affect the accurate measurement by the flowmeter. If less precision in the measurement results is required, these factors can be ignored; however, if more accurate data is desired, it is essential to pay attention to these three aspects. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content! http://www.yb1518.com/UploadFiles/20175239314754.jpg