Software for calculating aircraft aerodynamic coefficients

[phys_student1]

Hi,

I want a software that can generate aerodynamic coefficients (C_D, C_L, C_Y,C_l,C_m,C_n, etc)
I am aware of some specialized software (e.g. AVL, open source from MIT, LinAir Pro, commercial, etc).

But was wondering whether I can use 'common' software like AutoCAD Mechanical or Solidworks for this task? The reason is that these softwares are available in my university, so no need to buy any software.

 

[boneh3ad]

Some of those CAD programs have some limited fluid mechanics abilities, but they are going to be very limited. If you are looking for those values on an airfoil, you might try xfoil. Otherwise you would likely need to use something more fully-featured like Fluent.

 

[phys_student1]

Is ANSYS Fluent able to generate all drag and lift coeff. given an airplane geometry?

 

[boneh3ad]

I don't have enough direct experience with it to be able to tell you what it can generate automatically, but I know it can generate the whole flow over an immersed body (such as an airplane) and from that data you can calculate basically whatever you want. Of course, it would also depend on the turbulence model you decide to use as well.

 

[strive]

Ansys fluent will at least give you lift, drag and moment about any arbitrary axis. The same goes for solidworks floworks. Calculate the desired coefficients from the obtained data or simply set up equation goals before you start the simulation.

 

[phys_student1]

Thanks, I have just installed Autodesk Simulation CFD 2014 (free for students!).

If anyone knows a tutorial for using this software specifically for aerodynamic coefficients calculations, please tell me!

 

[jmex]

try QBlade or XLR5.. specially created for Aircraft analysis.

 

[Ryoko]

PanAir is free and will do it. However, getting your model into it is a bit of a challenge. I have a program that allows you to model you craft using Blender3D and then exporting it into a PanAir friendly format.

 

[RandomGuy88]

The problem with something like AutoCAD, Solidsorks or Fluent is that CFD is not trivial. It takes a lot of knowledge and experience to create a proper grid around your model and like boneh3ad mentioned you need to know something about turbulence models. Then you need a sufficient amount of computational power and this an be difficult if you want to simulate a full 3D aircraft.

If you can live without CD which is going to be the hardest thing to get anyways you could try a vortex lattice code like Tornado which is in Matlab, XFLR5 which is a mix of vortex lattice, panel method and lifting line, or a full 3d panel method like PanAir as was mentioned above.

Many of these codes will give a good estimate of lift and the many stability and control derivatives as long as you are not in the stalled regime in which case you probably will not get good results from CFD anyways.