The flow structure in the developing region of a turbulent jet has been examined using particle image velocimetry methods, considering the flow at steady state conditions. The velocity fields were integrated to determine the ratio of the entrained air speed to the jet speed, which was approximately 0.03 for a range of Mach numbers up to 0.89 and Reynolds numbers up to 217,000. This range of experimental Mach and Reynolds numbers is higher than previously considered for high-accuracy entrainment measures, particularly in the near-vent region. The entrainment values are below those commonly used for geophysical analyses of volcanic plumes, suggesting that existing 1-D models are likely to understate the tendency for column collapse.
Additional publication details
|Publication Subtype||Journal Article|
|Title||Experimental study of near-field air entrainment by subsonic volcanic jets|
|Series title||Journal of Geophysical Research B: Solid Earth|
|Contributing office(s)||Volcano Science Center|
|Description||B10203; 9 p.|