Software for calculating aircraft aerodynamic coefficients

Click For Summary

Discussion Overview

The discussion revolves around the search for software capable of calculating aerodynamic coefficients (CD, CL, CY, Cl, Cm, Cn, etc.) for aircraft. Participants explore various software options, including specialized tools and common CAD programs, and discuss their capabilities and limitations in the context of fluid mechanics and computational fluid dynamics (CFD).

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant inquires about the feasibility of using common software like AutoCAD Mechanical or Solidworks for generating aerodynamic coefficients, given their availability at their university.
  • Another participant suggests that while some CAD programs have limited fluid mechanics capabilities, they may not be sufficient for accurate aerodynamic calculations, recommending xfoil or more advanced software like Fluent instead.
  • There is a question about whether ANSYS Fluent can automatically generate all necessary drag and lift coefficients based on airplane geometry.
  • A participant notes that while they lack direct experience with Fluent, it can simulate flow over an immersed body, allowing for the calculation of various aerodynamic parameters, contingent on the chosen turbulence model.
  • It is mentioned that ANSYS Fluent can provide lift, drag, and moment data, and that Solidworks Floworks can also be used for similar purposes, with the possibility of setting up equation goals for simulations.
  • Another participant shares their installation of Autodesk Simulation CFD 2014 and requests tutorials for calculating aerodynamic coefficients using this software.
  • QBlade and XLR5 are recommended as specialized software for aircraft analysis.
  • PanAir is mentioned as a free option that can perform the required calculations, although challenges exist in getting models into the software.
  • Concerns are raised about the complexity of CFD, emphasizing the need for knowledge in grid creation, turbulence models, and sufficient computational power for simulating full 3D aircraft.
  • Alternatives like vortex lattice codes (Tornado, XFLR5) and panel methods (PanAir) are suggested for estimating lift and stability derivatives, particularly when avoiding stalled regimes.

Areas of Agreement / Disagreement

Participants express a range of opinions on the suitability of various software options for calculating aerodynamic coefficients. There is no consensus on a single best approach, and multiple competing views regarding the effectiveness of different tools remain evident throughout the discussion.

Contextual Notes

Participants highlight the limitations of common CAD software in performing complex CFD analyses, the necessity of understanding turbulence models, and the computational demands of simulating full 3D aircraft. These factors contribute to the uncertainty regarding the effectiveness of various software solutions.

Who May Find This Useful

This discussion may be useful for students and professionals in aerospace engineering, mechanical engineering, and related fields who are exploring software options for aerodynamic analysis and coefficient calculations.

phys_student1
Messages
104
Reaction score
0
Hi,

I want a software that can generate aerodynamic coefficients (CD, CL, CY,Cl,Cm,Cn, 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.
 
Engineering news on Phys.org
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.
 
Is ANSYS Fluent able to generate all drag and lift coeff. given an airplane geometry?
 
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.
 
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.
 
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!
 
try QBlade or XLR5.. specially created for Aircraft analysis.
 
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.
 
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.
 

Similar threads

Engineering I’m having second thoughts about my job position. How can I proceed with it?
  • · Replies 13 ·
Replies
13
Views
6K
  • Sticky
Physics Forums Global Guidelines
  • · Replies 2 ·
Replies
2
Views
505K