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Help with meshing normal to sloped surface

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 er18
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(@er18)
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Hi,

Great videos, a really easy to understand introduction to HyperMesh. 

I was wondering if there is a way to force the mesh to be perpendicular to an exterior surface. I have attached an example where the mesh generated in HyperMesh remains parallel to the principle axis XZ. What I would like is the mesh to be angled and perpendicular to the outer walls of the sloped area. Is this possible?

Thanks

 Straight Mesh
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Negative Volume
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(@negativevolume)
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Okay so I think I understand. You want to create a mesh along that angled edge but in the normal direction to the screen (y-z plane)? Is that correct?

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 er18
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@bossman

Yeah, I've attached a (terrible) drawing trying to illustrate what I mean.

 Terrible Drawing
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Negative Volume
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@er18

I’m not in front of my computer so I’m not sure this is right but you can go to the 2D tab and then either project, extrude, or drag should do what you are looking for. Just provide the direction for the drag so Z and then the distance for the drag and the element size. You can also create a plane on the x-y plane and move it to the position where you want to drag to. I’ll double check this later though.

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 er18
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@negativevolume

Apologies, I've just re-read what you wrote and realised that you weren't getting what I meant. I want to angle the current mesh on the XY plane so that it is perpendicular to the exterior edge.

I've attached my best attempt in Abaqus that was my previous attempt to get this right but the lack of control in Abaqus made me want to try HyperMesh.

Thanks,

 Structured Mesh on Gradient
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Negative Volume
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@er18

Ah I see, you want to extrude the shell into a solid mesh in the normal direction to the mesh. This can be done in the 2D tab and then "Elem Offset" and then select "solid layers." Select the shell elements with the "elems to offset" selected and click the down arrow next to "along geom to follow" and switch to "elems" and select the shell elements again. This is what will tell hypermesh that you want the solid mesh to stay normal to the original shell mesh. 

You can then change the options on the right however you like where layers is the number of solid elements that will be created in the thickness, total thickness is the thickness distance, and initial offset will actually offset the solid from the initial location of the shell (I don't think you are interested in that.) There are some other options where you can bias the size of the elements in the thru thickness and you can also change how the solid corners are model where it says "CFD corners."

Let me know if that accomplishes what you were looking to do. 

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 er18
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@negativevolume

Hi, sorry again. This is proving really difficult to explain.

I don't want to extrude it, I have a script that can revolve a 2D mesh for me in Matlab. What I'm looking for is just to rotate the mesh in the 2D plane so it is at 90 degrees to the exterior surface. I've attached a picture that should explain it much better than my previous attempts.

Thanks for your patience,

 Current v.s. Desired 2D mesh
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Negative Volume
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@er18

Okay, so that blue mesh from Abaqus is a shell mesh and not a solid mesh? Because that offset function that I mentioned before will create an aligned mesh like you are looking for but it will be a solid. You can also create a 2D shell from that created 3D part using Tool -> Faces -> And select all of the elements and click find faces. This will create a new component titled "Faces" which you will have to move the elements to a new component before exporting. 

Note: I know what you are saying about revolving a mesh and trying to align the elements, unfortunately I'm not aware of how to do that. The easier thing would be to recreate the mesh using the outer side of the mesh using the steps mentioned above so that the resulting mesh is oriented to your liking. 

To export the model you just click the red arrow at the top left and make sure you are on the option that looks like a mesh (solver deck) and make sure file type is LsDyna. Then find a save location using the folder icon and name it what you like .k and in Export: you can choose to export the whole model or just what is Displayed. I usually leave this on displayed to keep the files as small as possible. It will save the parts as well as just the nodes and elements so you may have to copy and paste what you want into other files that you already have.

I hope this is helpful. 

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 er18
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@negativevolume

Another quick question, If I wanted to export the node and mesh coordinates. Is there an easy way to do that?

thanks again,

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