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Victor
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These are a bit tricky. Contour plot resolution in particular. It was persistent in version 4 but several people turned it up to maximum then wondered why the display was so slow. It needs a way around this problem because the link between the resol…
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I agree about keeping incomplete solutions. The internal solver already does that and I hope to add it for CCX too. If you're starting CCX with a batch file, the cancel button won't end the process but if you're using ccx.exe directly then it shoul…
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Yes, I'd say so. I also found that changing the size of the room changes the frequencies of the other modes but not the 266.7 Hz one, further indicating that it's independent of the room's geometry, as you'd expect for a cavity mode. It's also a go…
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I don't think so because there's no *CONTACT keyword in CCX. Do you have complex self-contact where you can't predict the pairs in advance?
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I suspect the problem is that the pin has no forces or constraints to prevent it either rotating or sliding out of the hole. In real life, you'd expect it to just pop out as soon as it starts to bend because there's no friction and the reaction forc…
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There's a couple of formulas to convert damping ratio (ie 2%) to alpha and beta. The tricky part is that it only works correctly at two frequencies so you have to choose frequencies that are significant and tolerate increasing error further from the…
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I don't understand this much at all. What you say sounds reasonable about the frequency domain and that you'd need to do a bit of math to transform to real valued displacements which would be in the time domain. I think it only allows Rayleigh damp…
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Yes, uploading a file will be helpful. Contact often has strange ways of failing and needs playing around with to diagnose. One way is to use small time steps and ramp up the load. Then you might see that the final solution before it fails reveals …
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A restriction of Automesh 3D is that all the elements have to be oriented with their "upper" face in the same direction. If you turn on "Show element axes", it shows that one surface have backwards faces. You can reverse them using Mesh tools -> …
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It rotates about the center of a cuboid around the mesh. I realize there's a need for rotating about a custom point, especially when zoomed in. So that's something I hope to do for in future.
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Sí
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Mecway doesn't yet have any features for this, either with the internal solver or CCX. You'd have to define it by hand using *FREQUENCY and *STEADY STATE DYNAMICS steps. There could also be problems reading the solution data in because it's a functi…
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The time in nonlinear static analysis is only a pseudo-time which is used for counting but doesn't correspond to actual seconds. So the concepts of velocity and kinetic energy aren't really meaningful - the solution is the same regardless of how fas…
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I don't want to expose the node coordinate system concept in Mecway's interface but instead have directions directly included as part of the constraints. What feature of CCX are you using for bolt pretension? Is that the PRETENSION MPC or forces or …
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A modal analysis without damping doesn't provide that - there's no non-arbitrary way to scale the modes that would preserve any information. You would need a steady state frequency response where you impose a driving frequency and see what the sound…
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You can use a set of stress and plastic strain points to approximate the R-O curve. The example in the manual shows that. I'm assuming the plastic is isotropic despite the fiber reinforcement. Sergio would know more about materials than me though.
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It's a little simpler than that if you don't define the material in Mecway's own way too. There's an ELSET already there for each component so just add *MATERIAL, *ELASTIC, etc. See p126 of the manual ( http://mecway.com/manual.pdf ) for an example.…
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Centrifugal force isn't currently supported for exporting to CCX. See p122 of the manual http://mecway.com/manual.pdf for a list of which features are there. Instead, you can define it by entering the CCX command by hand in CCX -> custom step co…
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You have to switch to nonlinear analysis type for it to be enabled. That tends to be quite confusing especially since CCX automatically turns on geometric nonlinearities when you use a plastic material anyway, so I hope to clear this up in the next…
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There's "line pressure" which sounds like what you mean. Is it this?
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Not with Mecway's built in solver. If you use the 3rd party CalculiX solver, you can do this. You'll have to specify the displacement-time pairs by entering some commands though and not as a formula. The PipeClip.liml sample on p92 of the manual sh…
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They are already displayed as arrows. Can you clarify what you mean?
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It's because some environment variables aren't set. Either: - Use ccx.bat that's installed along with CalculiX, rather than ccx.exe. Beware that with a batch file, if you shut down Mecway while CCX is running, it can continue running silently in th…
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So this is a CCX bug in reading .inp files with CRLF vs LF?
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The modes are mass normalized where the mass matrix is that of a material of 1kg/m^3 density. That's just the default that the eigenvalue solver produces and there's no compelling reason for it. Though I know or someone who used that fact to do thei…
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1. Version 6 will have some more powerful local refinement tools for manual meshes. 2. That sounds like substructuring. Not something I give a high priority to since it's an optimization that could complicated to use.
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Hello thachmonkey It's relative - the pressures are scaled by an arbitrary factor that's different for each mode. The actual amplitude would depend on the source of sound and the damping in the room, neither of which are modeled by Mecway.
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Good point. It's using the Abaqus format with *BEAM SECTION but should be *BEAM GENERAL SECTION for CCX as you say. In the mean time, you would have to define this section type manually using custom model definition in Mecway.
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Although I haven't checked this case on Linux, the difference might not be anything to worry about. It could be that two same-frequency modes switched order or that they're physically the same mode but rotated one segment around the axis. Do you se…
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Yes, that's the general idea, though in this case I think it's a particularly difficult type of buckling - a toggle mechanism (aka "snap-through buckling") which means it can't be solved with the linear buckling solver which only does bifurcation bu…
