[Vitek]

Hi everyone,
I have been developing a simple 3D panel code from scratch. The code is using vortex ring panels, iterative solving of the wake etc. The method works reasonably well for external flow, I started with simple objects, then wings, then a propeller, but the main goal is a water turbine in a turbine case (internal flow) with high pressure drop between inlet and outlet. I calculated the pressure acting on panels as -0.5*density*velocity^2 and then realized this can't be right for this type of problem, where total pressure doesn't stay constant, as in external aerodynamics but drops from inlet to outlet. I can calculate the total pressure drop from the mechanical energy extracted by the turbine but I would like to get the cp distributions etc...

What is the correct approach to calculating the static pressure on the blade surface?

Any help would be highly appreciated

[Vitek]

Hi,
I will try to formulate my problem more generaly.

I have potential flow solver that will give me the flow field around a rotating turbine blade. How to calculate the pressure at the blade surface, when there is mechanical energy being extracted?

Thanks for any clues,

Vitek