Drag reduction by microbubble injection in a channel flow

C. del C, Y.A. Hassan, J.A. Jiménez Bernal, J.G. Barbosa Saldaña

Abstract


The injection of microbubbles within the turbulent boundary layer in a channel is investigated to elucidate the drag reduction phenomenon. Experimental data for a fully developed flow were obtained using the Particle Image Velocimetry (PIV) technique for single-and two-phase flow. Both cases are compared to examine the effects of the presence of microbubbles within the boundary layer, specifically the modification of vorticity, vortex structures, and fluctuating rate of strain, which is directly related to the energy dissipation in turbulent flows. A notorious decrease in the rate of strain as well as vorticity was observed for the two-phase flow. These results are significant and will help to reveal the physical mechanism of drag reduction by injection of microbubbles.

Keywords


Microbubbles; drag reduction; channel flow

Full Text:

PDF

Refbacks

  • There are currently no refbacks.


Revista Mexicana de Física

ISSN: 2683-2224 (on line), 0035-001X (print)

Bimonthly publication of Sociedad Mexicana de Física, A.C.
Departamento de Física, 2o. Piso, Facultad de Ciencias, UNAM.
Circuito Exterior s/n, Ciudad Universitaria. C. P. 04510 Ciudad de México.
Apartado Postal 70-348, Coyoacán, 04511 Ciudad de México.
Tel/Fax: (52) 55-5622-4946, (52) 55-5622-4840. rmf@ciencias.unam.mx