Expert: Mark Janus - 2/14/2008

Question
Hi, Dr. Janus. I'm a aeronautical engineering student. I'm fascinated with the Coanda effect. I have some questions about it:
-Are there any equations for modeling curves that could be use  for generate Coanda effect?
-Can Coanda effect be generate with a succession of straight sections rather than use a curve?

Thanks for your attention,

David C.

Answer
Well the "equations" would be the Equations of Fluid Motion (EFM) but I don't know of any particular simplification for "dealing with" the Coanda effect...   basically the equations can be used to determine how pressure varies with streamline curvature and how pressure and velocity vary along a streamline....  basically whether its viscous effects that  keep a flow attached to a surface or cause it to separate, the Euler equations (inviscid equations of fluid motion) still relate pressure and velocity along and normal to the streamline...  ultimately it is the fluid pressure difference (bottom to top) that gives rise to an object (no pun intended)...

A succession of straight sections could be used, bearing in mind that at every surface discontinuity (in slope) the propensity of the flow to separate (from the surface) will be increased....

Thanx,
mj