The STL file was created for storing information about 3D objects. During creation and exporting your Geometry as a surface mesh you should be able to control density or smoothness of your stl file, or try to export a high quality stl file. Other option will be .obj files, but alle of the surface meshes (.stl or .obj) must be triangulated. (triangle mesh Not Hexa-mesh) In order to run snappyHexMesh you will need a polyMesh directory first, it means you need to make a hexahederal background mesh. The mesh generation algorithm works in the following steps: 1. Creation of background (initial mesh using blockMesh or other Softwares - it should be a simple block, and must fills the entire region ) 2. Cell splitting at edges (surfaceFeatureExtract) 3. Cell spilitting at surfaces 4. cell removal and local refinement (castellatedMeshControls) in snappyHexMeshDict file 5. Snapping to surfaces and layer creation (snapControls) in snappyHexMeshDict file Check out the source code to understand how SHM works -> github.com/OpenFOAM/OpenFOAM-2.1.x/blob/master/applications/utilities/mesh/generation/snappyHexMesh/snappyHexMesh.C In this tutorial i just edited blockMeshDict file in order to create my own backgroundMesh. enjoy! ArD
I understand, thank you. However, I would like to ask one more question ... if you wanted to keep the original mesh of the monkey.stl, could you?! And so the OF would adapt to imported mesh ...
In my case, Cd should be around 0.032 You Need to write an extra Expression in paraview to calculate Cd coefficient as follows: C_D= F_D/(0.5* ρ* U^2*A)
At the end of the video, as soon as i switched the Attribute mode to the cell Data, i got the my drag and lift forces in Newton and also an area (which is equal to 10,36 m^2) and i can use it as my reference area to calculate my cd coefficient!!
I have a car model that I want to find the cD on. If I just import the model as a .stl file and copy all that text in the video word for word, will this work for my car model, or does every single model have totally different codes that you need to know ? Well of course it would. So how does one find out what code to write for each object they are testing ? The video would be very useful with some voiceover expaination of what you are doing. -Thanks
Super well done! Thanks for sharing.
Marcos Lourenço g
What is 'subl' on 4:45?!
(subl)Sublime is my text editor.
Why did the monkey have an all-structured mesh when you imported it and after using snappyHexMesh did the mesh break up ?!
The STL file was created for storing information about 3D objects. During creation and exporting your Geometry as a surface mesh you should be able to control density or smoothness of your stl file, or try to export a high quality stl file. Other option will be .obj files, but alle of the surface meshes (.stl or .obj) must be triangulated. (triangle mesh Not Hexa-mesh)
In order to run snappyHexMesh you will need a polyMesh directory first, it means you need to make a hexahederal background mesh. The mesh generation algorithm works in the following steps:
1. Creation of background (initial mesh using blockMesh or other Softwares - it should be a simple block, and must fills the entire region )
2. Cell splitting at edges (surfaceFeatureExtract)
3. Cell spilitting at surfaces
4. cell removal and local refinement (castellatedMeshControls) in snappyHexMeshDict file
5. Snapping to surfaces and layer creation (snapControls) in snappyHexMeshDict file
Check out the source code to understand how SHM works -> github.com/OpenFOAM/OpenFOAM-2.1.x/blob/master/applications/utilities/mesh/generation/snappyHexMesh/snappyHexMesh.C
In this tutorial i just edited blockMeshDict file in order to create my own backgroundMesh.
enjoy!
ArD
I understand, thank you. However, I would like to ask one more question ... if you wanted to keep the original mesh of the monkey.stl, could you?! And so the OF would adapt to imported mesh ...
What "Cd" did you get?
In my case, Cd should be around 0.032
You Need to write an extra Expression in paraview to calculate Cd coefficient as follows:
C_D= F_D/(0.5* ρ* U^2*A)
At the end of the video, as soon as i switched the Attribute mode to the cell Data, i got the my drag and lift forces in Newton and also an area (which is equal to 10,36 m^2) and i can use it as my reference area to calculate my cd coefficient!!
Tariq Khamlaj you can use the hydraulic diameter for that
I have a car model that I want to find the cD on.
If I just import the model as a .stl file and copy all that text in the video word for word, will this work for my car model, or does every single model have totally different codes that you need to know ?
Well of course it would.
So how does one find out what code to write for each object they are testing ?
The video would be very useful with some voiceover expaination of what you are doing.
-Thanks