Center of pressure problem

ranger1716

I have some intro aeronautical class homework problem that is giving me difficulty.

I need to find the center of pressure for the upper surface of an airfoil in terms of percent chord from the leading edge. I know that the chord lenth is 1m. The pressure from the top surface of the airfoil starting at the chord is 3N/m. The pressure from the bottom surface of the airfoil starting at the chord is 1N/m. There is no angle of attack and I do not know the velocity of the incoming air.

Do I need to use the equation Cp=Pt-P/1/2pv^2 ?

I can't understand how to use this equation in the context of this problem.

Any help pointing me in the right direction would be appreciated

Astronuc

Center of pressure (cop). The point at which the aerodynamic lift on a rocket is centered. (from http://www.daviddarling.info/encyclo..._pressure.html)

Perhaps try this approach as applied to the foil.

http://www.grc.nasa.gov/WWW/K-12/airplane/rktcp.html

ranger1716

I've looked at methods similiar to what was on that page, however I don't think I have enough information from that problem to use this method.

Do I have to know the velocity of the incoming flow in order to determine the center of pressure? I have a sort of triangle made for determining the center of the triangle. However, I only know the length of one side-the base is 1m. I know the pressure acting on another side, but that's all.

enigma

Can you give the exact wording of the problem?

ranger1716

"Find the center of pressure for the upper surface of the airfoil (in terms of %chord from the leading edge)."

I was trying to get the picture from the problem posted up here, but I haven't been able to so far.