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Mechanisms of Two and Three-Dimensional Base Drag

  • D. J. Maull

Abstract

The mechanisms of the production of low pressure on the base of two-dimensional and axisymmetric bluff bodies are discussed. The factors which can influence this pressure are described, with emphasis on the effects of the presence of some three-dimensionality on basically two-dimensional base flows.

The differences between two- and three-dimensional base flows are highlighted, firstly by discussing the effects of tip geometry on a high-aspect-ratio bluff-based body, and then by discussing a very simple three-dimensional bluff body. Some results are given of an investigation into means of influencing the base pressure of this simple body, and the effect of the proximity of the ground is considered.

Keywords

Strouhal Number Vortex Generator Bluff Body Rectangular Block Reattachment Point 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notation

A

Aspect Ratio

Cd

Drag Coefficient

Cp

Pressure Coefficient

Cpb

Base-Pressure Coefficient

\({{\tilde{C}}_{px}}\)

Modified Pressure Coefficient

ΔCp

Differential Pressure Coefficient

d

Body Thickness

h

Height Above Ground, Step Height

L

Length

n

Plate Width

p

Pressure

S

Displacement Surface

u

Velocity

x, y

Coordinates

α

Angle of Incidence

δ

Boundary Layer Thickness

ν

Viscosity

δ

Density

ω

Vorticity

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References

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Copyright information

© Plenum Press, New York 1978

Authors and Affiliations

  • D. J. Maull
    • 1
  1. 1.Cambridge UniversityCambridgeEngland

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