DOI: 10.1615/TSFP6
DRAG FLUCTUATIONS ON DEFORMED BUBBLES IN A TURBULENT SHEAR FLOW BY MEANS OF DNS
SINOPSIS
In this study, the direct numerical simulation of a fullydeveloped turbulent channel flow with deformed bubbles
were conducted by means of the MARS method, turbulent
Reynolds number 150, and Particle Reynolds number 120.
As the results, large scale wake motions round bubbles were
confirmed. At the bubble related region, mean velocity was
degreased and turbulent intensites and Reynolds shear stress were incresed by the effects of the large scale wake motions round bubbles. On the other hands, near wall region, effects of bubbly flow might act on flow laminarlize and drag reduction.
Two types of drag coefficient of bubble were estimated
from the accelerated velocity of bubble and experimental
equation as a function of Particle Reynolds number. Drag
coefficient estimated by the accelerated velocity of bubble
was below the results estimated by the experimental
equation.