Large-scale turbulent/turbulent entrainment of mass and momentum in planar wakes

Turbulent entrainment denotes the spatio-temporal process by which turbulent flows expand by incorporating ambient fluid into the primary turbulent flow, e.g., the growth of a volcanic plume with distance from the crater or growth of a jet of pollutants being discharged into the atmosphere or hydrosphere. This research aims to investigate the effects of free-stream turbulence on the large-scale entrainment (engulfment) of mass and momentum into the canonical turbulent wake produced by a cylinder, using simultaneous planar laser-induced fluorescence (PLIF) and particle image velocimetry (PIV) measurements. The wake region will be marked with a passive scalar that faithfully tracks the motion of the flow within the wake. Engulfed fluid can be identified as pockets of ambient fluid (regions of low scalar concentration) within the boundaries of the wake from the PLIF images. The entrained mass and momentum in these pockets are subsequently estimated using the velocity data, provided by the PIV technique. This will, for the first time, shed light on the role of engulfment in wakes subjected to a turbulent background, as compared to a quiescent ambient…

Faculty Supervisor:

Susan Gaskin

Student:

Partner:

Imperial College London

Discipline:

Engineering

Sector:

Education

University:

McGill University

Program: