PDA

View Full Version : Viscous Flow and Pressure Coefficient


snido727
Nov2-09, 12:04 AM
1. The problem statement, all variables and given/known data
What effect does a large positive dCp/dX have on the real viscous flow? This is for an airfoil design project using thin airfoil theory + vortex panel method.




3. The attempt at a solution
As far as I know Viscosity is independent of pressure, so the only thing I can think of is assuming ideal gas behavior and saying that it affects the density and therefore the kinematic viscosity. However I believe that he is referring to something different, some property of a viscous flow that I haven't yet figured out.

Thanks in advance.

snido727
Nov2-09, 09:56 AM
Can anyone help me? I don't need the answer so much as a nudge in the right direction...ie "look at x property"

Thanks again

gamer_x_
Nov2-09, 03:28 PM
in which dimension is flow?

snido727
Nov2-09, 03:30 PM
The design is in 2 dimensions.

snido727
Nov3-09, 08:27 PM
Well for anyone else who stumbles upon this and needs the answer look at the difference between the lift coefficient vs. angle of attack graph for viscid vs. inviscid flow, and consider how the coefficient of pressure affects the lift coefficient.