Laser Doppler Anemometry (LDA), also known as Laser Doppler Velocimetry (LDV), is an optical technique ideal for non-intrusive 1D, 2D, and 3D point measurement of velocity and turbulence distribution in both free flows and internal flows.
Laser Doppler Velocimeters have several strong features:
- Measure velocity components directly
- Good spatial resolution (down to <1 mm)
- Good temporal resolution (up to >1 kHz)
- Wide velocity range (0 to hypersonic)
- Measure the sign of the velocity in reversing flows.
- Linear response to velocity
- Calibration given by the laser wavelength and the intersection angle between the beams.
Researchers in science and industry use our Laser Doppler Anemometry (LDA) system to gain a clearer understanding of fluid mechanics. The measurement results are important steps in fine-tuning product designs to improve aerodynamic efficiency, quality, and safety.
The signal processor is a very important part of a Laser Doppler Velocimeter: in challenging applications, the Signal-to-Noise Ratio (SNR) is often low, so the processor must robustly extract the signal from seeding particles passing through the measurement volume (bursts), and determine their frequency which is proportional to the velocity, whilst rejecting false signals from noise. The Burst Spectrum Analyzer (BSA) is the market-leading LDV processor with a proven track record.
We have several thousand Laser Doppler Velocimeter systems installed worldwide, used in very diverse applications ranging from bio-fluid mechanics to rocket science. Most LDV systems are installed on water channels or wind tunnels, and they are used both for education and for fundamental or applied research as well as for optimization of aerodynamic or hydrodynamic performance of vehicles, airplanes, ships, pumps, turbines, combustion engines, and many others.