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dculp
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I think this wouldn't matter as long as you search for any "edges" that don't actually belong to an enclosed area that is defined by other edges.
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@Sergio - I searched your link for "gmsh", "group", and "component" but couldn't find the script. Do you have a different link or who posted the script? Thanks, Don C.
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When your algorithm identifies surface edges, perhaps it could run a final check on the identified edges to eliminate any disconnected lines such as these.
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If the mesh parameter "Min number of elements per edge" is increased from 1 to 50 then the mesh is greatly refined relative to the curvature. However, the extraneous surface lines remain but shortened from 0.003 mm to 0.0002 mm. Thus, I suspect that…
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Here is some info from the Autodesk model files -- H1001a__Autodesk_partial_model_image H1001a__Autodesk_material_properties. These values, when converted, agree with Mecway. (Mecway doesn't explicitly state the shear modulus.) H1001a__Autode…
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Sergio -- Your custom commands work well. However, they generate additional nodes at the center of the elements. (I don't understand why these nodes were generated or what they are for since they aren't connected to anything.) These can be deleted …
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Thanks. Note that if you don't check Recombine all triangular meshes and then you click Mesh\Define\Recombine 2D to convert to quads, then Mesh\Define\Experimental\Optimize quad topology doesn't work. Instead, checking Recombine all triangular mes…
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Attached is the step file (H1010b.stp). Also, see my latest post (gmsh - How to change the 2D quad element size?) which uses the same step file. Note that the problem mesh discussed here was generated by Mecway 18, not gmsh. My intent with these …
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The Autodesk log file shows that element compatibility is not enforced. I seem to recall that this results in reduced element stiffness (correct me if wrong). If Mecway's tet elements enforce compatibility, could this be why the Autodesk brick mode…
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Thanks for spotting the dimensional error in the Mecway brick models -- all models should have been 40 mm diameter. (The person who created the incorrect models has been severely reprimanded ) Still, I wonder about the Autodesk results. Although …
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Victor -- I'm interested in the axial mode at 20 kHz and the adjacent slightly higher bending mode to see their interactions. When resonances are closely spaced, small differences in the frequency separations can have large effects on the interacti…
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disla -- This gives the correct stress (1000 Pa). However, any value of the second moment of area (other than 0) gives the same stress. (Try 1e-10, 1e+10) In a way this makes sense since the beam isn't bending (pure axial load). I guess the solver …
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disla -- For the static analysis with a scale factor 1, the FEA displacement at the free end of the beam is +1 m. The model has been set up with a modulus of 1000 Pa, an area of 0.001 m^2, and a length of 1 m so that the beam's axial stiffness k …
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disla -- Also, I see only one reference in Mecway's manual to "stress in element coordinates" and couldn't find any in the CCX manual. Where can I find more info?
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disla -- There are a number of "stress in element coordinates". I tried 2 that seemed possible (s.uu.1 and s.uu.u) on the static model but both gave the same problem. Can you upload the corrected static model and/or the dynamic model?
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Beam model -- no stresses or strains calculated. The attached beam-mass model (KM_32a.liml) is the same as I posted yesterday (KM_31a.liml) except that I'm trying to determine the stresses and/or strains in the beam as the model oscillates. For a g…
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prop_design -- I am curious about your CCX modal problem. I do a lot of modal analysis with CCX and so far have not encountered such problems. If you can upload your designs I can have a look. If you upload, it would be most helpful to have both t…
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The L4 error results from lack of beam density. If the beam density is set to any low value (e.g., 1e-10 kg/m^3) then the 2nd moment of inertia has no effect (as long as nonzero). If the 2nd moment of inertia is 0 then the error is "Rigid body mode …
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disla -- Your example works well for the spring element. I tried applying this to the beam design (modifying modal KM_10b.liml). Dynamic model KM_20a.liml uses the CCX solver. It gives the following solver errors -- I then changed the model to…
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disla -- That works. Thanks. (I may have some follow up questions regarding dynamic analysis of such models, likely in another post.)
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In the above example, a 1m peak displacement was chosen for convenience to show the equivalence of the FEA relative stress and the theoretical stress. Of course, such a displacement is unrealistic for an actual material. My interest is displacements…
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prop_design -- i just wouldn't go around saying you are computing stress with modal analysis. that will not go over well with people familiar with the topic. You are correct if you are asserting that absolute stresses can't be determined with mod…
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I ran the attached modal model (86k nodes) under two conditions -- 1) with usual stress calcs; 2) without stress calcs (per Victor's suggestion of deleting all stresses from the solution tree before calcs). I alternated between the two conditions, r…
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A typical modal analysis CCX solver output (abbreviated for clarity) is below. I'd like to stop the solver after the eigenmodes have been calculated. This would prevent the stress calcs which I often don't need. (For this particular analysis there w…
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For a particular analysis, I'd like the stresses to not be calculated to begin with so that the run time would be reduced. I thought there might be a CCX card that would prevent the stress calcs.
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v.17 is slower than v.16 for modal analysis? The following table shows the run times for the attached model (alternating between v.16 and v.17 while the other version was closed) -- Version --- Time "Solver exited" --- Total time (results displaye…
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I'll look forward to it. Thanks.
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Thanks for the proposed improvements. Since I want to publish to my website, any guess about the release date for v18?
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For "\Solution\Surface integral" and "\Solution\Sum", it would be helpful to be able to specify "selected nodes" or "selected surfaces" on-the-fly after the solution has finished, rather than having to specify these entities beforehand as "Named sel…
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Can ngmesh.exe be run as a stand-alone program? If so -- * On what file(s) does it operate (the liml file or what)? * Can you give an example of syntax / optional parameters?
