Mechanisms of Two and Three-Dimensional Base Drag
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.
KeywordsVortex Convection Shrinkage Vorticity Suffix
Modified Pressure Coefficient
Differential Pressure Coefficient
Height Above Ground, Step Height
- x, y
Angle of Incidence
Boundary Layer Thickness
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