If I make a simulation of a wing and want to investigate the lift coefficient for multiple angles of attack I can change the free flow direction by keeping the Ux speed constant and changing the uy speed over time. To achieve this I make a graph for the velocity inlet . The problem with this is that the lift and drag is aligned with the ux direction even if the direction of the flow is changing and not to the direction of the free flow as normal in aerodynamics. Because of this I cant compare the results with X- foil for example.
To have the lift and drag aligned with the flow direction as in a wind tunnel I have to change the angle of attack on the cad model for each angle I want to analyze or is there a better way to solve this.
What I would like to be able to do is to have the possibility to change the angle of the cad model during the simulation, in the same manner as a rotating Wall, with a rotation point and axle direction and specify the angles of attack in a graph. In the post processing all values for the different angles of attack could form a lift sloop curve.
Hi Stefan, and welcome back to the forum!
You don’t need to go to such extreme to analyse multiple angles of attack. A simpler approach would be:
- Use only one CAD model, with a proper enclosure.
- Perform multiple simulations, each one corresponding to one angle of attack.
- For each simulation, change the inlet velocity vector and the lift/drag directions in the result control item to be consistent with the angle of attack. Be aware that some inlet/outlet faces might have to change also.
This should be enough to optimize your time and effort, please let me know if something is not clear from my explanation.
Here are some links that should help you in the process: