Pictures of an Initial Separation (2D)

The pictures show a cross section of a cylinder that experiences a gust of air coming from the left. The blue and red colors indicate the boundary layer, consisting of air that has been retarded by the cylinder surface. To be precise, when the cylinder surface retards the air, it gives it a spinning motion called vorticity: the color indicates how fast the air is spinning around and in what direction.

Click on any picture for a larger version.

• The same process at half the air velocity
• The same process at double the air velocity
• The same process at one sixth the air velocity, compared to experimental data
• Look at rebounding vortices

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