Applied Scientific Research

, Volume 42, Issue 3, pp 245–263 | Cite as

Pressure field around three-dimensional bluff bodies

  • B. H. L. Gowda
  • H. J. Gerhardt
  • C. Kramer
Article

Abstract

The pressure field on the ground plane around three-dimensional bluff bodies with varying relative dimensions has been obtained experimentally. The pressure measurements along the plane of symmetry are presented for the cases when the bodies are exposed to a uniform approach flow (without the presence of a horse-shoe vortex) and when the bodies are kept in a boundary layer. The results show extreme base suction for a body with a relative length to width ratio (l/b) of 0.5. A horse-shoe vortex exists at the front end for the bodies kept in the boundary layer. The isobaric coefficient contours presented for the region away from the plane of symmetry clearly indicate the regions of suction pressure around the bodies and how they vary with the relative dimensions. The vortex system at the front end is also revealed by the isobars.

Keywords

Vortex Boundary Layer Pressure Measurement Relative Dimension Pressure Field 

Nomenclature

b

width of the body

CPW

(p−pr)/1/2ρU r 2 , pressure coefficient on the ground

h

height of the body

l

length of the body along the flow direction

p

pressure at any point on the surface plate with the body

pr

pressure at the same point on surface plate without the body

Ur

free stream reference velocity

x

coordinate along the flow direction

xr

reattachment distance

z

coordinate normal to x and in the plane of the ground

δ

boundary layer thickness

δ*

displacement boundary layer thickness

Superscript

(-)

( )/b

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Copyright information

© Martinus Nijhoff Publishers 1985

Authors and Affiliations

  • B. H. L. Gowda
    • 1
  • H. J. Gerhardt
    • 2
  • C. Kramer
    • 2
  1. 1.Department of Applied Mechanics, Indian Institute of TechnologyFluid Mechanics LaboratoryMadrasIndia
  2. 2.Department of Aeronautics, Fachhochschule AachenFluid Mechanics LaboratoryFederal Republic of Germany

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