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Victor
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Comments
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Here it is. I changed the last bonded contact's value and remeshed the parts with Fit midside nodes to geometry on all of them.
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This solution uses bonded contact instead of contact so it's not really the same problem. Lateral loads on the bolts will be distributed around the entire circumference of the hole instead of only on the side that the bolt presses against. So the st…
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Yea, ANSYS works out the contact stiffness automatically but here you have to pick a value. There's also a lot of trouble with CCX if a part is only supported by contact (not bonded contact). I'd guess that most of the support emails I get are about…
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That's intentional. An example of a use is line3 elements revolved to form a quad8 cylinder. Or a tri3 shell is easier to create manually than tri6 and can be converted later.
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It turns out that it fails if you open the file as millimeters but works OK as meters! That's pretty surprising. It seems like Netgen prefers bigger coordinate values (60 mm is sent to Netgen as 0.06). Here's the mesh I made anyway - you'll have to…
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No, sorry. You would have to build one from translational springs. Either make a moment arm with another beam element or, perhaps more elegantly, use a constraint equation to couple the rotational DOF of the beam element to the translational DOF of …
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I didn't have a problem meshing that with the default settings. Though with quadratic elements, turning off Fit midside nodes to geometry prevents some badly shaped elements appearing.
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The lines following *MATERIAL,NAME=YourMaterialName
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No need because it'll still be sharing the same nodes.
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What I find easiest is to extrude a small element (select a face then Mesh tools -> Extrude) and assign it a new material with low Young's modulus and apply fixed support to the new face. It ends up looking like this picture. The next version of…
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@Sergio > Is there a way that the mehs of the first part (from imported geometry) goes directly on the default component? I'm thinking it'll have to stay the way it is because it's hard to know the user's intent for that default component. If …
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The problem is in the the teeth part and their fixed support, but not the contact. I'm a bit surprised at that and it even happens when I delete the entire mesh except for a single element. But some elements are OK even though the look just as reaso…
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Since this is so thin, I think you should extrude the old surface mesh (Mesh tools -> Extrude) instead of using Automesh to create a volume mesh. By extruding, you'll get prism elements which are a little better than tetrahedra from Automesh 3D. …
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The *ERROR will be where it failed. CCX stops when there's an *ERROR, but keeps going with *WARNING. The view options don't affect how the contact is applied, as long as you don't select the edges of the elements. It should also work just as well w…
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There are lots of ways for convergence failure to happen, and unfortunately it's quite common with contact. Here are some general ideas: Run it as Quasi-static (in Analysis settings) and ramp all the loads using formulas (eg. 3*t instead of 3). Tha…
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That's incredible! Thanks for creating all those Mecway tutorials. Is SimCommons a business? How does it make money?
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I think you uploaded the wrong file since it has no constraints or contacts. *WARNINGs in CCX are common and usually harmless. My guess is that this wouldn't be a problem since a fully fixed surface can't rotate so maybe it doesn't need any MPCs to…
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Thanks for adding that but I'm going to have to get a bit ranty - Stress intensity is awful. It's apparently the same thing as stress intensity range, so good luck describing a range of stress intensities! Does intensity here have any common meaning…
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The internal matrix solver is already multi-core. I don't expect to make anything else use multiple cores. The graphics card shouldn't have much effect on performance because the bottleneck for all the slow parts of the graphics is the CPU/RAM. Tho…
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Yes, I intend to add rigid body too.
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Not usually. But it's hard to tell from the picture if there's anything else going on. If you're using the CCX solver, those kinds of sharp corners with large thickness can sometimes cause it to fail. There will likely be more error in that region …
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The graphics are only single-threaded.
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That's probably just an artifact of the display if there are sharp corners since it displays each element as a prism.
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Yes, I'll add point mass for CCX soon. Center of gravity is going on the list but I can't promise.
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You can use Shell offset under Mesh tools -> Element properties to move the midplane by half the thickness.
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Unfortunately, offset shells won't be correct with dynamics because the offset is ignored in generating the mass matrix. That means the mass is at the mesh nodes while the stiffness is offset, so there's a spurious rotational inertia. If you don't m…
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Yes, it does disk swapping when it detects there's not enough RAM. The solver (Pardiso) also optimizes the ordering in the matrix so there's no need to consider node numbering in the model. Bonded contact creates constraint equations between each …
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This is pretty unscientific but I found 21 sources (journal articles, books, FEA software manuals) that describe the Tresca criterion: 3/21: Tresca stress refers to maximum shear stress 1/21: Tresca stress refers to 2*maximum shear stress 2/21: Tre…
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Will it be OK if you can just control the color instead of thickness? The mesh lines are the same thickness and I guess they're visible enough because of the contrasting color. This idea of selecting things in the graphics area is hard and I probab…
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Yes, fixed nodes can be used with contact because it's done with elastic springs so it's not subject to possible conflicts of MPCs the way bonded contact can be. But you should be able to fix only the surface, not the whole interior. If you fix the…
