Study of the near-wake structure of asubsonic base cavity flowfield using PIV

M. J. Molezzi, J. C. Dutton

Research output: Contribution to conferencePaper

Abstract

A new particle image velocimetry (PIV) system has been used to study the near-wake structure of a two dimensional base in subsonic flow in order to determine the fluid dynamic mechanisms of observed base drag reduction in the presence of a base cavity. Experiments were done over a range of freestream Mach numbers up to 0.8, including local flowfield velocities over 300 m/s. Effects of the base cavity on the von Kármán vortex street wake were found to be related to the expansion and diffusion of vortices near the cavity, although the effects are of small magnitude and no significant change in the vortex formation location or path was observed. The base cavity effects are also less significant at higher freestream velocities due to the formation of vortices further downstream from the base. The base cavity drag reduction was found to be mainly due to the displacement of the base surface to a location upstream of the low-pressure wake vortices, with only a slight modification in the vortex street itself.

Original languageEnglish (US)
StatePublished - Jan 1 1993
EventAIAA 23rd Fluid Dynamics, Plasmadynamics, and Lasers Conference, 1993 - Orlando, United States
Duration: Jul 6 1993Jul 9 1993

Other

OtherAIAA 23rd Fluid Dynamics, Plasmadynamics, and Lasers Conference, 1993
CountryUnited States
CityOrlando
Period7/6/937/9/93

Fingerprint

near wakes
particle image velocimetry
Velocity measurement
Vortex flow
cavities
vortex streets
vortices
drag reduction
Drag reduction
wakes
subsonic flow
Subsonic flow
fluid dynamics
Mach number
upstream
Fluid dynamics
low pressure
expansion

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electrical and Electronic Engineering
  • Aerospace Engineering
  • Engineering (miscellaneous)

Cite this

Molezzi, M. J., & Dutton, J. C. (1993). Study of the near-wake structure of asubsonic base cavity flowfield using PIV. Paper presented at AIAA 23rd Fluid Dynamics, Plasmadynamics, and Lasers Conference, 1993, Orlando, United States.

Study of the near-wake structure of asubsonic base cavity flowfield using PIV. / Molezzi, M. J.; Dutton, J. C.

1993. Paper presented at AIAA 23rd Fluid Dynamics, Plasmadynamics, and Lasers Conference, 1993, Orlando, United States.

Research output: Contribution to conferencePaper

Molezzi, MJ & Dutton, JC 1993, 'Study of the near-wake structure of asubsonic base cavity flowfield using PIV', Paper presented at AIAA 23rd Fluid Dynamics, Plasmadynamics, and Lasers Conference, 1993, Orlando, United States, 7/6/93 - 7/9/93.
Molezzi MJ, Dutton JC. Study of the near-wake structure of asubsonic base cavity flowfield using PIV. 1993. Paper presented at AIAA 23rd Fluid Dynamics, Plasmadynamics, and Lasers Conference, 1993, Orlando, United States.
Molezzi, M. J. ; Dutton, J. C. / Study of the near-wake structure of asubsonic base cavity flowfield using PIV. Paper presented at AIAA 23rd Fluid Dynamics, Plasmadynamics, and Lasers Conference, 1993, Orlando, United States.
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