LDV: Laser Doppler Velocimeter
Particle velocity and turbulence measurements
Laser Doppler Velocimeter (LDV) is a well-known technique for measuring the velocity of individual particles non-intrusively in a flow field. The method was invented in 1964 by Yeh and Cummins. The particles being measured are either naturally present in the flow or are added to track the flow. Small particles can track the flow with high fidelity and, as a result, measuring the particle velocity provides an accurate estimate of the local flow velocity.
Artium continues to advance the state-of-the-art in Laser Doppler Velocimeter (LDV) instrumentation. Artium’s LDV systems offer turnkey operation with a fully automated setup feature. The optical transceiver can be used for the real-time, non-intrusive measurement of individual particle velocity and turbulence measurement (1 or 2 velocity components) in a variety of flow applications. An optional 1-D transceiver can be used along with the 2-D transceiver for the simultaneous measurement of 3-components of velocity.
The complete instrument includes an optical transceiver, ASA signal processors, data management computer and the AIMS software. The high-powered DPSS lasers built into the transmitter provides stability, compactness, ruggedness, and high reliability; it eliminates the need for inefficient and unreliable fiber optics and bulky Ar-ion lasers.
The Fourier transform based Advanced Signal Analyzer (ASA) incorporates a proprietary digital signal burst detection technique and adaptive Doppler burst sampling approach to provide high accuracy in signal detection and measurement.
The Artium Instrument Management System (AIMS) provides fully automatic setup and operation of the instrument. A variety of standard and user-configurable views are available to analyze the data. It also offers remote operation and monitoring via the Internet.
The compact LDV design incorporates several features aimed at ease-of-use and data accuracy. A new version of the ASA is now available for improved data accuracy at high speeds and in difficult environments. The AIMS software includes an auto-setup feature that automatically selects the processor and optics settings for optimal performance in complex flows.
Artium offers a variety of optical designs, including custom designs, to meet different flow applications. Systems capable of measuring droplet size and 1-, 2-, or 3-components of velocity are available. Laser wavelengths and power can be customized based on the application and user needs.