Laser Grating technique for measurement of local velocity of large drops and jets in liquid-liquid systems

✍ Scribed by Raphael Semiat; Enna Leshinski; Aluf Orell

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 980 KB
• Volume: 51
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/s0009-2509(96)00349-1

✦ Synopsis

Measurements of the local rise velocity of large liquid drops of 3-7 mm in diameter and the local axial wave propagation velocity on a liquid jet surface in liquid-liquid systems were successfully performed using a Laser Grating Velocimeter (LGV). The primary frequency of the photodetector signal that is required for evaluation of the local velocity, was determined unambiguously by a frequency-domain Fast Fourier Transform analysis of the velocity signal. The validity of this technique, which eliminates potential measurement errors, was confirmed by a controlled experiment. The LGV was applied to the determination of the drop terminal rise velocity distribution of a population of 300 drops, and axial distribution of the jet surface wave velocity in order to demonstrate the capability and effectiveness of the technique.