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LDA flow sensors

Especially interesting for manufacturers of laser doppler anemometers and power plant operators

24.03.2015

Laser Doppler Anemometry (LDA) measures the velocity in liquids optically - i.e. contact-free. A procedure developed at PTB to determine the position of the measuring volume considerably reduces the uncertainty of volume flow determination when calibrating flow sensors by means of LDA. From the power of the backscattered laser light, the path of Flow velocity measurement In a pipe· (left: LOA probe; right: optical access) the interfering beams is reconstructed and the interference fringe interval, the position and the size of the measuring volume are determined. LDA enables the calibration of flow sensors, for example in power plants, at temperatures up to 230 °C and at a pressure up to 40 bar.

Advantages

- Determining the position of the LDA measuring volume with high precision

- Reducing the measurement uncertainty

- Calibrating at high temperatures and high pressures

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