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Hi, this is the Industrial Control Assistant. Today, once again, I’m the hardworking little bee sharing useful industrial control knowledge – let’s learn together with the Assistant! There’s useful information available every day. Gas vortex flow meters and gas turbine flow meters are of the same type. A gas turbine flowmeter is a device that uses a multi-bladed rotor (turbine) to detect the average flow velocity of the fluid, thereby determining the flow rate or total volume. Gas vortex flow meters are designed and manufactured based on the Karman vortex street principle. Flow rate is measured by applying the principle of fluid oscillation. As the fluid passes through the vortex flow transmitter in the pipeline, two rows of vortices are generated alternately above and below the vortex generator, which is a triangular prism; these vortices are proportional to the flow velocity. The frequency at which these vortices are generated is related to the average velocity of the fluid flowing past the vortex generator as well as the characteristics of that vortex generator. In a gas turbine flow meter, under certain conditions, the rotational speed is proportional to the flow rate. The fluid being measured impacts the turbine blades, causing them to rotate; the rotational speed of the turbine changes as the flow rate changes – that is, the higher the flow rate, the greater the rotational speed of the turbine. A magnetoelectric conversion device then converts this rotational speed into electrical pulses of corresponding frequency. After being amplified by a pre-amplifier, these pulses are sent to a display instrument for counting and showing. The instantaneous flow rate and cumulative flow rate can be determined based on the number of pulses per unit time and the total number of pulses accumulated. Features of gas turbine flowmeters: 1. Good repeatability, with short-term repeatability ranging from 0.05% to 0.2%. It is precisely this excellent repeatability that allows for very high accuracy through regular calibration or online calibration, making them the preferred choice for flow measurement in commercial transactions. 2. Outputs a pulse frequency signal, suitable for total quantity measurement and connection to computers; it features no zero drift and strong interference resistance. 3. It can generate high-frequency signals (3–4 kHz) with strong signal resolution. 4. It has a wide range of ratios; for medium and large diameters, the ratio can be 40:1 to 10:1, while for small diameters it is 6:1 or 5:1. 5. It has a compact and lightweight design, is easy to install and maintain, and features high flow capacity. Gas vortex flow meters are developed based on the Karman vortex principle, and are primarily used for measuring the flow rate of fluids in industrial pipelines, including various media such as gases, liquids, and vapors. Gas vortex flow meters use piezoelectric stress sensors, offering high reliability, and can operate within a temperature range of -20°C to +250°C. It provides both analog standard signals and digital pulse signals for output, making it easy to integrate with digital systems such as computers; it is a relatively advanced and ideal measuring instrument. Features of gas vortex flow meters: 1. Gas vortex flow meters are a new type of flow meter that utilizes the principle of fluid vibration; they are used in industries such as petroleum, chemicals, metallurgy, and papermaking to measure the flow rate of liquids and gases in pipelines. 2. The flow meter has no moving parts, offering high reliability, precision, and a long service life; it can measure both the instantaneous and cumulative flow of liquids over a wide range of flow rates. It is not affected by medium temperature, pressure, viscosity, or composition; it does not get clogged or stuck, is resistant to scaling, can withstand high temperatures and pressures, is safe and explosion-proof, and is suitable for harsh environments. 3. The gas vortex flow meter features a simple structure; the vortex transmitter is installed directly on the pipeline, which eliminates the problem of pipeline leakage. In addition, gas vortex flowmeters have low pressure loss and a wide measurement range; the ratio of the measurement range for saturated steam can reach 30 to 1. 4. The installation location should minimize the impact of steam hammers within the pipes on the vortex street generator. Gas vortex flowmeters should not be used when vibration is high and cannot be eliminated.