Help with Autodesk Simulation Multiphysics

[GIJOE500]

I want to calculate the lift and drag force on an airfoiil that I made.

Using Autodesk Inventor, I made an airfoil, with a box around it, and saved it as an STEP file. I loaded this file in simulation multiphysics, generated the mesh, and then specified the inlet outlet conditions. 

I know I have to specify the analysis parameters, but I do not know what to specify them as.

If you have any tips on what I should do next, or whether I should do this a different way, please respond. 

[Joey.X]

Refer to previous thread for the lift/drag force calculation 

http://forums.autodesk.com/t5/Autodesk-Simulation/Lift-and-Drag-Force-Calculation/m-p/3206338#M2531

Notes that there are two options for 2D airfoil

- Using 2D planar analysis for pure 2D profile (preferred) 

- Using 3D calculation by extruding 2D mesh in depth direction for one layer element

Note ASIM/MP is limited in turbulence models under 2D planar option, so ASIM/MP can have good prediction for laminar model, but less accurate for turbulence model because of separation location prediction. User has another option to try ASIM/CFD which has more turbulence model. 

[GIJOE500]

Thank you very much, I really sppreciate your help. 

I stumbled upon a problem while following the steps in the thread that you provided me.

When I run the simulation, I get an error telling me something along the lines of something that went wrong with the iterations and convergence and also to try using the "sparse solver." I set the solving method to sparse, but I still got the same error. 

Also, the airfoil I want to test is a 3D model, and I do not know how to set the analysis parameters.

I am just a beginner, so all of this is kind of overwhelming. 

Thank  You

[Joey.X]

Could you post your simulation log files(.lgu for unsteady , or .lgf steady analysis), screen cuts or the archived model if you don't mind and the archive is under the limit of uploading boundary ?

[GIJOE500]

I attached the lgu file. I tried it once more but I am getting a different error now.

[Joey.X]

For unsteady fluid flow, please check global parameter window/time and loads curve definition on this error.

Or please share your screen cut  for this window. 

[GIJOE500]

Thank You so much.

There is also another project that I am working on. I made a model of a balsa wood car that I plan on making, and I want to test its drag and lift in Simulation multiphysics as well. I followed the same steps for this one as I did the last one. Howver, I have no clue at all as to how to set the parameters. If I attached the file of my model, would you be able to set the parameters for me?

I want the wind to be aroung 22 m/s and I want to run the simulation for around 5 seconds. 

Thank You

[Joey.X]

Please attach your archive model, use archive instead of a single .fem file.

[GIJOE500]

How exactly do I make it into an archive model?

Sorry, I'm such a beginner to all of this. 

[Joey.X]

From File/Archive/Create, then in "Include files", select "Model and result".

After archiving is done, you will find a new file YourModelName.ach

[GIJOE500]

I made the archive file and I tried to it as a part of a zip file. However,, I think the file is too large.

I have a dropbox link though, at: http://dl.dropbox.com/u/55303902/WindTunnelTest.zip

I want to change the material of Parts 1 and Part 2, but I am unable to. If you do not mind, can you do that for me a well. 

I would like the wind to be aroung 22 m/s and I want to run the simulation for around 5 seconds.

Please tell me if there is any thing additional for me to do. 

Thank you very much. 

[GIJOE500]

I was unable to attach the file, even in a compressed zip file because it was too large.

I do however have a public link to the file at dropbox.

http://dl.dropbox.com/u/55303902/WindTunnelTest.zip

Please tell me if there is anything additional for me to do.

Thank you

[Joey.X]

hi, GIJOE500

Thanks for sharing the archive model, it is found that the imported CAD needs the fluid domain. In other word, please do boolean operation in CAD to produce pure fluid part, for this case, box (part3) - (part 1+part2) = fluid part, then input into ASIM.

Could you do the operation and share the  .stp file?

[GIJOE500]

Ok, I am not sure if I did exctly what you wanted.

I joined the Part 1 and Part 2, so that it is now a single part. I saved this file as an STP file.(First One)

I also made another STP file, annd I subtracted Part 2 and and Part 1 from Part 3. I also attached this file. (Second One)

 When I was saving as an STP file, an error log file waas created, I do not know if this is a problem, but I attached those files as well. 

[Joey.X]

The "second file.zip" is what I want, however, I got meshing difficulty for this model because of the model complexity. Some of the remedies is using smaller box to enclose the car and suppressing the small features in the car. This is a trade off  between simulation accurancy and modeling  complexity. 

Could you resend me the model using the style of "second file.zip"? Thanks.

Below is failed temporary mesh.