FreeCAD CFD- External Flow Analysis Example|JOKO ENGINEERING|

[@icojb25]

Hahaha, I've never been called "knock your socks off amazing" before. Lol. Thanks.

[@JokoEngineeringhelp]

Wow, it's an honor to have one of the developers here. Being on the mechanical side, sometimes the development side feels a bit like magic. Thanks for making your efforts so accessible and making these tools as great as they are.

[@brunof1734]

Thanks for the FreeCAD content and CFD analysis. This will help future engineers.

[@jaco1159]

This was incredible. As someone with very little experience with CFD I was able to follow along from your download file.

[@SomeTechGuy666]

Great video. At 20:00 or so you could have made the airplane more visible by decreasing the opacity of the streamlines. This the best/easiest/clearest way of meshing for OpenFOAM that I've found. Good work !

[@dr_workaholic]

I love this channel and the work you do. This is my go to source for FreeCAD info, thank you 🙏

[@c8y8r8]

Dear Joko, you have done a very detailed demo, good job, Bravos

[@JokoEngineeringhelp]

Thanks!

[@brunof1734]

Joko I suggest making FreeCAD videos explaining the Assembly 3 Workbench. As a former Solidworks user I think this workbench is intuitive and in my opinion it should be the main Assembly workbench

[@brankelly1921]

Really appreciate the video, you say you’re not a pro at Paraview but you sure are to noobs like me. Thanks!!

[@terrylembke8100]

I Liked your simulation video , Joe . great work . If you could do a comparison video on the assembly work benches . Perhaps advantages and disadvantages of each one and maybe with examples ?? I know that may be a lot of work , but please consider . Thank You Merry Christmas to you and yours and a great new year to all . Kindest Regards Terry Lembke

[@SomeGuyInSandy]

Sweet! it looks fun and frustrating at the same time, lol!

[@avejst]

Wow, impressive simulation A bit difficult thou Thanks for sharing your experiences with all of us :-)

[@Gumball_W]

Trust me that the CfdOF module in FreeCAD is the most intuitive open-source CFD software. Pretty much everything else (including OpenFOAM itself) requires digging deep in input files and programming languages.

[@hanshans7491]

Thanks for this tutorial it's very helpful

[@RixtronixLAB]

Cool tutorial, well done, thanks :)

[@Gumball_W]

This Floating point exception error should disappear without the need to remesh with different size if you just switch initialization from potential flow to specify values (you can leave the default zeros there).

[@JokoEngineeringhelp]

Great tip, thank you!

[@j121212100]

I could not get anything working with Simscale but have been able to sucessfully get some results using Openfoam workbench for FreeCAD on a laptop with only four cores and 8GB of memory. Workflow seems more streamlined for CFDOF plugin.

[@PaukSK]

Nice, thank you.

[@Poduhvat]

Is it possible to do wind induced rotation simulation in this software? Like for example to determine wind turbine rotation speed under the influence of wind and rotor power?

[@Gumball_W]

It's possible in OpenFOAM using Arbitrary Mesh Interface and 6 DOF library but it's not supported in CfdOF.

[@Zaladquiel]

With Paraview you can use less points (I saw 1000) and downscale the point cloud. Or use a line rather than a sphere for the stream lines. Also turn on the plane geometry. Can you do a demonstration with an external flow on a building? If you can generate a CFD flow with atmospheric boundary layer profile (decreasing velocity from the top height to bottom) it would be awesome.

[@JokoEngineeringhelp]

Lets see what I can do on that! I haven't tried using a velocity gradient but I think that would be a super interesting analysis

[@Radar_Contact]

When I try to remove propeller, also half of the plane disappears. Why is that?

[@GemstoneActual]

Nice walkthrough; thanks. Outro sounds Ratatat-ish. ;)

[@ChânLýHay]

Very good enjoyed watching stay connected friend.. Hello Have a great day..🌷

[@protograde2723]

I'm not getting the plot after running the solver. Am I missing something?

[@JokoEngineeringhelp]

Possibly. I have a series on setting up FreeCAD for CFD. It requires add ins for some things. This is the first video in the series: kzbin.info/www/bejne/m32QinWmeJmjbKs

[@xelonix_]

The video I was really looking forward to. Thanks! The streamline results are in MPa or in terms or m/s? Also, it would be best if we have a good Paraview tutorial.

[@Nebb1e]

Love the video so far, using it for a school project, but a quick question, I made an aircraft in Open-VSP and exported it as an STL, I followed the instructions and couldn't get past the cutting/halving of the plane. It gives me the error "Recompute failed!". if you have any idea on how to fix this it would be greatly appreciated.

[@JokoEngineeringhelp]

Is there anything along the plane body that might register to the kernel as zero thickness geometry?

[@Nebb1e]

I can't seem to find anything visible that would cause it to be zero thickness, I downloaded your model so I could see how it went but I got another error when computing the mesh in cfdOF, saying that the installation path hasn't been set and couldn't be found.

[@Nebb1e]

I got the installation path to work, but now i'm getting an error message whenever I click run mesher stating "Meshing exited with error."

[@JokoEngineeringhelp]

@@Nebb1e This is a common thing in the world of analysis. Change meshing parameters and mesh types might help. Even consider changing the shape if you need to. Sharp edges and/or unusual angles, unusually small features may all be causes.

[@LT72884]

awesome video. Thank you for recommending it to me. I do have a question. I am new to CFD. I understand the math very well, but what i am trying to understand is why the negative cut of the plane? why not just leave the plane as a solid? or does freecad not like overlapping geometry? How does having a empty shell vs solid part calculate flow? And why do we need a wall? whats its purpose? EDIT: i figured out why we need walls. I didnt catch what you said, but htis box is a "virtual wind tunnel" so no walls would be an issue. thanks

[@JokoEngineeringhelp]

I'm not a career analyst, so my answer probably isn't the best. Making a negative of the plane establishes the area/boundary that flow will occur in, and allows you to define where the flow starts, ends, what acts as a wall, etc. Great to hear from you, Best!

[@jaco1159]

Is there a reason we don't enforce no-slip on the surface of the plane? Maybe with air it doesn't have a large impact.

[@Gumball_W]

Surface that aren't explicitly selected for boundary conditions have default boundary condition (slip wall) assigned.

[@Akwitful]

No matter what i do, i get Simulation Error :(

[@Akwitful]

I do not get the mode: "CorsairResiudals" Just after some second error

[@SLU2MOVIES]

And I was trying to figure out how to get it running :D yesterday. But damn first I need to install openfoam on windows xD

[@djdelta777]

He is using openfoam which is already a workbench within Freecad, so no need to install

[@c8y8r8]

Dear Sir, I could not fine the CfdOF function in my 0.19 version, is your demo version 2.0 ?

[@JokoEngineeringhelp]

This will work in version 0.19. Start here and watch subsequent videos. kzbin.info/www/bejne/m32QinWmeJmjbKs

[@rcane6842]

Are you able to put floating debris and able to analyze its behavior as it 'collides' with the aircraft?

[@Gumball_W]

It would be extremely difficult to simulate in OpenFOAM, let alone CfdOF. You would likely need FSI and thus coupling with a structural solver (like CalculiX) for this. Even then I'm not sure if contact would work.

[@antoine1407]

Can I export this mesh to openfoam?

[@c8y8r8]

Dear Sir, my model is not symmetrical in certain wind directions, and therefore I need to include it in the box tunnel. is there a demo for this

[@JokoEngineeringhelp]

It should work if you make the box go over the whole part instead of half of it

[@engineerdeva2975]

Do you have simulation of flare or combustion using free Cad

[@JokoEngineeringhelp]

There wouldn't be a simulation of a combustion itself, you could simulate multiple materials and the flow as they mix and you could do another analysis of what the max possible combustion pressures would be on your components. I haven't heard of FEA that has this capability, but Ansys might since it's so advanced and heavily used in aerospace. Likewise Cyprien Rusu has some good material on FEA, he might have a guide for it on an open source free platform like Salome. feaforall.com

[@Gumball_W]

OpenFOAM has a special solver called fireFoam for that. But it’s not supported in CfdOF module in FreeCAD.

[@SomeTechGuy666]

@@Gumball_W What can't OpenFOAM do ?

[@cayenne7792]

My first look at FreeCad and all I want to know is: Can you turn off orthographic perspective? And why would you ever turn on an unrealistic 3D view?

[@JokoEngineeringhelp]

Yes if I understand your question. View>toggle orthographic or perspective rendering. Not distorting the model for perspective viewing is the standard in every platform I've used, because when modeling it is quite important to have correct, nonscaled features for relations and constraints on external geometry.

[@cayenne7792]

@@JokoEngineeringhelp That is what the ortho views are for (top, left, right, back, etc.) Heck make any ortho view ya want with a working plane. My brain struggles to figure out which way the model is orientated with ortho perspective especially in wire frame, no problem at all in normal perspective plus i get to see what the model really looks like especially if we can adjust focal (lens) length

[@gabril0205]

really interesting! if i wanted to simulate a car including wheel rotation, what should i do? can you make a tutorial like this for this topic too? thank you very much, very clear video

[@DANTHETUBEMAN]

Just model wheels as stationary, I no open wheel will creat wing life effects. I don't think it's enough to worry about. Indi cars stay on the ground

[@gabril0205]

@@DANTHETUBEMAN thank for the reply!

[@yakdaymar6659]

😀😀😀😀😀

[@joellegge460]

CFD with tetraeder mesh refinement zone is not a good idea

[@Gumball_W]

It’s just a surface visualization. If you open the mesh in ParaView (there’s a button for this) you will see that it’s actually a hex mesh.

[@JokoEngineeringhelp]

Public Dislikes: Only Like This Comment If You Dislike The Video.

[@CHITUS]

Joko I suggest making FreeCAD videos explaining the Assembly 3 Workbench. As a former Solidworks user I think this workbench is intuitive and in my opinion it should be the main Assembly workbench

[@j121212100]

now i know which Assembly plugin to try. there are so many. i didn't know which one i really should be using.