Is there a way to calculate the Drag coefficient from any given object?

[BasNijhof]

Hi guys, for my final high school project I want to create a simulation in Unity (A game engine) in which you should be able to make an airplane fly with extremely accurate physics. In the regular formula for Drag is: Fd = 1/2 * ρ * v^2 * Cd * A. I can get all these things except the Drag coefficient. How could I possibly calculate or at least estimate the Drag coefficient with just an airplane model in Unity?

 

[A.T.]

Hi guys, for my final high school project I want to create a simulation in Unity (A game engine) in which you should be able to make an airplane fly with extremely accurate physics.

And you are only asking about drag, not lift?

This is a software that does what you want, but it's rather complex:
https://en.wikipedia.org/wiki/X-Plane_(simulator)#Flight_model

 

[bigfooted]

Just to be clear, with high school you mean the dutch 'vwo' (secondary education) and not the dutch 'hogeschool' (university of applied sciences)?

Computing the drag in real time is practically impossible for arbitrary shapes and flying conditions... It is even very difficult to compute it in the first place. However, if you are working with predefined airplane models, you can store the known aerodynamic characteristics of such an airplane in arrays and matrices and work with only the equations of motion of the plane to determine its flight path and response, without solving the aerodynamics around the plane. For instance a 6dof model, which is the basis of many flight simulators. Is this what you are after? This is already very challenging for a high school student in my opinion.
Some examples in MATLAB are given by Stengel, who also happens to have written a book about it. Here is some free information from one of his lectures:
http://www.stengel.mycpanel.princeton.edu/MAE331.html
http://www.stengel.mycpanel.princeton.edu/MAE331Lectures.html

Hope this helps...

 

[Leo Liu]

And you are only asking about drag, not lift?

This is a software that does what you want, but it's rather complex:
https://en.wikipedia.org/wiki/X-Plane_(simulator)#Flight_model

I would recommend Flightgear since it is an opensource project. I think OP could ask his question on its forum.