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『Spiral vortex gas flowmeter』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
1. Working principle of vortex flowmeter
The working principle of vortex flowmeter is based on the alternating arrangement of vortices generated by fluid passing through vortex generators, and the flow rate is calculated by detecting the vortex frequency. 1. Core working principle: When the fluid flows into the flowmeter, it first passes through a set of spiral guide vanes and is forced to rotate to form a vortex. After entering the expansion section, this vortex generates a spiral motion, and its center moves around the central axis of the instrument like a spiral line. The vortex frequency is proportional to the flow velocity, and the flow rate can be calculated by detecting the vortex frequency through a piezoelectric sensor. 2. Key component functions: Vortex generator: a specially designed spiral blade structure that forces the fluid to rotate. Sensor: usually piezoelectric, detects pressure fluctuations caused by vortex frequency. Signal processor: converts the frequency signal into a standard current signal (4-20mA) or digital signal. 3. Technical features: Measurement accuracy: ± 1.0% to ± 1.5% (liquid), ± 1.0% to ± 2.0% (gas). Range ratio: usually up to 10:1 or 15:1. Working temperature: -40 ℃ to+300 ℃ (depending on the sensor type). Pressure rating: up to 25MPa. Application precautions: Installation required. Ensure that the length of the front straight pipe section is ≥ 5DN and the length of the rear straight pipe section is ≥ 3DN (DN is the pipe diameter). Not suitable for low flow velocity measurement, the minimum flow rate needs to maintain the Reynolds number within a specific range. Media containing solid particles or fibers may block vortex generators and require the installation of filters. <
2. What flow meters are used for CNG filling measurement?
CNG filling measurement mainly uses three types: turbine flow meters, vortex flow meters, and Coriolis mass flow meters.
. 1. The turbine flowmeter adopts the principle that the turbine speed is proportional to the flow rate, with high accuracy (± 0.5% - ± 1%), good repeatability, and wide range ratio (10:1 to 20:1). However, it requires high fluid cleanliness, and impurities may block the virtual wheel and cause measurement errors.Pressure and other parameters have an impact, but the equipment cost and installation requirements are relatively high. All three types of flow meters must comply with the requirements of the national standard GB/T 32201-2015 Gas Flow Meter. The actual selection needs to be comprehensively evaluated based on accuracy requirements, fluid characteristics, and budget.
3. Working principle of vortex flowmeter
The flow profile of the flow sensor is similar to the profile of a Venturi tube.
. Place a set of spiral guide vanes on the inlet side, which force the fluid to generate intense vortex flow when it enters the flow sensor. When the fluid enters the diffusion section, the vortex flow is subjected to backflow and begins to undergo secondary rotation, forming a gyroscopic vortex precession phenomenon. The precession frequency is proportional to the flow rate and is not affected by the physical properties and density of the fluid. By measuring the secondary rotation precession frequency of the fluid with the detection element, good linearity can be obtained over a wide range of flow conditions. The signal is amplified, filtered, shaped, and converted into a pulse signal proportional to the flow rate