Right Angle Vortex Gas Flow Meter(Welded) LSU-99A-DF

Measurement Principle：

The LSU-99A Series Gas Vortex Flow Meter operates on the Kármán vortex street principle. It combines the characteristics of both vortex flowmeters and electromagnetic flowmeters, which belong to the category of velocity-type flow measurement instruments.

The operating principle is illustrated in Figure 1.

The bluff body is mounted within the measuring pipe. An insulated electrode rod is installed at a specified distance downstream of the generator, with a pair of permanent magnets vertically aligned between the generator and electrode.

When fluid flows past the bluff body at velocity V, alternating vortices are produced on both sides of the generator, forming a “vortex street” (Figure 2). These vortices intersect the magnetic flux lines perpendicularly, generating periodic induced potential pulses. Within defined Reynolds number ranges, the vortex shedding frequency f on a single side exhibits linear proportionality to the fluid velocity V, as defined by the following formula:

f=St·V/d

Where:

V: Fluid velocity on both sides of the generator (m/s).

d: Characteristic width of the bluff body’s flow-facing surface (m).

St: Strouhal number, a constant within specific Reynolds number ranges for a given bluff body geometry.

With fixed pipeline and generator geometry, the flow rate QV becomes directly proportional to frequency f. The weak frequency-dependent signals are amplified, shaped, and processed via microprocessor to generate display readings and standardized outputs (e.g., 4–20 mA).

Gas Vortex Flow Meter Selection

Model Coding:

Overview:

The Right Angle Gas Vortex Flow Meter LSU-99A-DH/DF is specifically designed for oilfield water injection systems, available in two configurations: one with flange connection (DH) and the other with welded type (DF). Both flowmeter variants can directly replace common turbine-type water meters and high-pressure electronic water meters, finding extensive applications in measurement operations at oilfield water injection sites and water distribution stations.

Features:

1.Electrodes and piezoelectric crystal probes offer low resistance to liquids, reliable performance, and a long service life.

2.The flow meter core is detachable, facilitating convenient calibration and maintenance of the instrument.

3.Outputs pulse signals proportional to flow rate with no zero drift.

4.Features integrated temperature and pressure compensation.

5.Low pressure loss, suitable for metering sandy sewage and clean water.

6.The LCD displays instantaneous flow, cumulative flow, and allows daily water injection volume to be queried.

Specification:

Installation Size:

Note: The above external installation size is for reference only. Users are advised to provide detailed size before ordering.