LU series vortex flowmeter is a kind of fluid vibration flow sensor, which is suitable for measuring the flow of superheated steam, saturated steam, compressed air and general gas, water and liquid.

1. The sensor has no moving parts, simple and firm structure, stable performance and long service life.

2. The internal design and layout of the sensor are reasonable, the pressure loss is small (about 1/4 ~ 1/2 of the orifice flowmeter), and the maintenance amount is small.

3. The measuring range is wide, up to 15: 1 or 20: 1.

4. Flange clip connection or plug-in connection is convenient and simple to install and easy to operate.

5. Output a pulse signal proportional to the flow (which can also be converted into 4 ~ 20 mA), which is suitable for total metering without zero drift.

6. It is universal and can form a metering control system with the flow totalizer produced by Tianqi Company or other manufacturers.

Vortex flow sensor is based on Kaman and Strouhsl's theory about the generation of vortex and the relationship between vortex and velocity to measure flow. When the medium flows through the triangular cylinder at a certain speed, an alternating vortex zone is generated behind the two sides of the triangular cylinder, which is called "Carmen Vortex Street" (see the figure below).

Because eddy currents are alternately generated on both sides of the vortex generator, pressure pulsation is generated on both sides of the generator, so that the detector generates alternating pressure. Under the action of alternating stress, the piezoelectric crystal element encapsulated in the probe generates an alternating charge signal with the same frequency as the eddy current. The amplifier amplifies, filters and shapes this charge signal, and finally outputs a pulse signal (or a signal whose frequency is proportional to the flow rate of the medium), which is sent to the integrator for processing, display and control.

In a certain Reynolds number range (2× 104 ~ 7× 106), the relationship between vortex release frequency f and fluid velocity v and vortex generator width d is f = St v/d, where St is Strouha number and is a dimensionless coefficient. As long as the frequency f is accurately measured, the fluid velocity v can be obtained, and the volume flow can be obtained from v.

Shanghai Meng Hui vortex flowmeter.