Wind bouncing off surfaces

What are the physics of wind (or any gas flow really) bouncing off surfaces?

If a wind hits a wall directly (in a 90 degree angle) does any of it bounce back?

Are there any similarities with, say, light rays hitting a mirror?

I understand, that the other extreme case is a 0 degree angle in gas pipes, for example, where the surface guides the flow further.

If a wind hits a wall directly (in a 90 degree angle) does any of it bounce back?

No, because air behaves like a continuous fluid, it can't rebound and flow back through itself without interacting with the fluid behind it.

The air will all be displaced sideways. There will be a higher pressure in front of the wall.

Are there any similarities with, say, light rays hitting a mirror?

None that I can think of.

Vortices in a fluid can bounce off walls. Ref. Ref.

A stream of fluid can bounce off a fluid surface. Ref.

But none of these are like wind hitting a wall or like light-rays hitting a mirror.

This question is hard to answer, because the terms don't fit. While you can model a ball as point mass, which can bounce, you model a flow as vector field, which in general can't. Bouncing fit's to a rigid object, not to a field.

Contrary a sound wave, with a gas as carrier medium (correct term?), can bounce analogous to light, because the reflected wave doesn't interact with the original one, see http://en.wikipedia.org/wiki/Superposition_principle

For a starter try http://en.wikipedia.org/wiki/Fluid_mechanics