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Victor
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I see. It looks like the AI is trying to editing the mesh instead of applying a displacement constraint. You can do a radial prescribed displacement without a script, using formulas in Displacement like this: If you need to adjust the distance in…
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You can do that with Mesh tools -> Move/copy, Set Coordinate system to Cylindrical (Z axis). But if you do need a script, could you please format the script to "Code" in the forum otherwise indenting is lost and other things get changed. Is it …
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Shell offset doesn't currently work with OpenRadioss. I'm not sure if OpenRadioss even has that capability? I see that Mecway allows you to define shell offset and doesn't give any error message. This is wrong and I'll make it clear that it won't wo…
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I'm not sure. It looks like it has read equivalent plastic strain from the CCX output because it's showing zero instead of nothing. Perhaps have a look at the .frd file to see if there should be non-zero values on those nodes.
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This looks like a bug Disla found https://github.com/Dhondtguido/CalculiX/issues/129 for heat flow which has apparently been fixed in CCX 2.23.
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Happy to hear that Jachym! You can also come here if you have any questions - there are some very knowledgeable and helpful people around.
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40/(0.9*1.565) is half the length of the bridge (unit is meter) so that it starts from the -x end instead of the origin. unittriangle(w,x) is this with area = 1. You add a constant to x to shift it in space, and add a multiple of t to make it shift…
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I get the same displacement at the center deck node at t=20 s. What is the difference you're seeing?
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You may have to defeature the geometry (in CAD) by removing the tiny radius on the trailing edge. Looks like that's what Fatmac did too?
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I'll change the traction unit from MPa to Pa because there's a unit conversion factor in there that makes it more confusing to me: -(180/4.3) * unittriangle(0.5, (0.9*1.565)*t-40/(0.9*1.565)-x ) the unittriangle() function defines a force per unit…
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See Gmsh for how to install it, then when it's installed, click Browse ... and find gmsh.exe. Don't copy the path in my screenshot because it'll be different.
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Gmsh isn't included with Mecway but you can download it from https://gmsh.info/ and set it up in Mecway using Tools -> Options:
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The length is still 500 mm (the first argument, 0.5, to the unittriangle function). You can visualize this by refining the mesh enough to see a patch of arrows. I changed 500 to 1000 in the constant term to somehow scale it to agree with your formul…
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I'm not sure if CCX can handle a decrease in the stress-strain curve. It doesn't have the *TENSION CUTOFF keyword, and the *PLASTIC stress-strain data has to be non-negative (stress is von Mises), so you can't define it there. It does, however, ha…
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Cool. Seems like a CCX bug? Lengths of 0.0001 are pretty small for usual units (mm, in) but it should be able to tolerate that.
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That's normal but it should converge towards something as time step gets smaller. In this case, acceleration has such big high frequency components, I don't think 0.01 s fine enough too big to capture it. Maybe add damping to suppress those if they…
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Those peaks of stress on the rivets might be spurious due to the contacts or the re-entrant corners under the heads. One on the end has the slave faces extending beyond the master faces. I corrected that and it slightly reduced the stress. If you …
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Yes, the displacement pre-tension is probably the right one and it does have that problem of having to decide the displacement. One way is to first solve with the Force option, measure the resulting displacement, then set that as the Length adjustme…
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Sorry, contact state for elastic contacts doesn't work with quasi-static. I'll make the error message clearer.
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1-I'have been thinking for a long time that when analysis is performed with Automatic time stepping, by default, the load is ramped from 0 at time 0 to 100 % at end time automatically too. There was no need to multiply by time in the formula. Tha…
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Quasi-static with contact sometimes converges worse than non-quasi-static because of the extra *STEP section Mecway inserts to prevent CCX from adjusting the contact stiffness (probably to help convergence!). During this extra step, the solver panel…
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Hello Disla, always a doozy when you find a problem! I didn't look at the SOL and reaction force results which I'd say aren't really part of Mecway, but the displacements changing with time isn't supposed to happen. I made a simpler model without …
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You can use Node-surface coupling with the RBE2 option and applied to the edges of both holes to fix them together rigidly. Pick any node on the hole edge as the reference node. Or to allow the holes to deform, use two RBE3s with their reference …
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The values in the outline tree are rounded to 3 s.f. The more accurate values are in the window.
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@disla I like that idea but I don't think it's safe or practical to predict all the node forces CCX might apply, including gravity, pressure, MPC forces, and their changes with large displacements.
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Because of this serious bug Fatmac found in loads & constraints groups, I've rolled back publishing version 31 on the download page. The bug is new fixed in version 32 which is available here https://mecway.com/download/mecway320.msi and that w…
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Pick Solution -> Force and moment -> External force then solve again. CCX only outputs external force, which is reaction force and applied force together. At constrained nodes with no applied force, like your anchored end, it's the same as rea…
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With the CCX solver, you have to use external force instead of reaction force.
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Oh! This is a new bug with Groups in Loads & Constraints. Thanks for reporting it. I'll make a quick update soon.
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Good to hear it helps, and thanks for showing me what a problem file size was. There's even greater saving after solving in v31. Just doing open and save still keeps it in double precision to ensure fidelity but solving again goes to single.
