Effect of bubbles on the turbulence near the exit of a liquid jet

✍ Scribed by S. Kumar; D. N. Nikitopoulos; E. E. Michaelides

• Publisher: Springer
• Year: 1989
• Tongue: English
• Weight: 707 KB
• Volume: 7
• Category: Article
• ISSN: 0723-4864
• DOI: 10.1007/bf00187067

✦ Synopsis

The objective of this paper is to examine the effect of bubbles on the turbulence levels of a water jet. Simultaneous measurements of the axial and radial velocity components were taken in a bubbly jet with a Laser Doppler Velocimeter (LDV) and then compared to the velocities of a single phase jet at the same liquid flow rate. Mean bubble diameters ranged from 0.6 to 2 mm and the void fractions were up to about 20%. The liquid Reynolds numbers were from 5,000 to 10,000 approximately. The measurements extended to from an axial distance of 4-12 cm. It was observed that bubbles did not affect significantly the average velocity profiles in the jet. However bubbles increased the turbulence intensities in the core of the jet near the jet exit. The increase in turbulence intensities was more pronounced at lower Reynolds numbers and at higher void fractions.