Laser Doppler Anemometry — Lesson 5

This lesson covers the operational principle of the Laser Doppler Anemometry (LDA), a noninvasive flow measurement technique used to measure the flow velocity at a point. The lesson explains how LDA uses the Doppler effect to measure flow velocity, with a detailed discussion on the mathematical analysis involved. It also highlights the advantages of LDA, such as its ability to measure velocity in situations where the fluid is acidic, corrosive, or contaminated. The lesson further explains how the shift in frequency, detected by a photomultiplier tube, is directly related to fluid velocity.

Video Highlights

01:21 - Explanation of noninvasive flow measurement techniques
09:30 - Explanation of the basic principle of measuring flow velocity using LDA
14:51 - Detailed mathematical analysis of LDA
44:20 - How the Doppler shift or shift in frequency can be directly correlated to the fluid velocity

Key Takeaways

- Laser Doppler Anemometry (LDA) is a noninvasive technique used to measure the flow velocity at a point.
- LDA uses the Doppler effect to measure flow velocity. The shift in frequency, detected by a photomultiplier tube, is directly related to fluid velocity.
- LDA has several advantages, including its ability to measure velocity in situations where the fluid is acidic, corrosive, or contaminated.
- The mathematical analysis involved in LDA is generic and applicable to almost all light-based techniques.