# Uncategorized **URL:** https://calculix.discourse.group/c/uncategorized/1.md?page=1 [Latest](https://calculix.discourse.group/latest.md) · [Categories](https://calculix.discourse.group/categories.md) **Page:** 2 --- ## [Convergence issue with small load](https://calculix.discourse.group/t/convergence-issue-with-small-load/2737)
**Author:** [@kraviteja](https://calculix.discourse.group/u/kraviteja)\ **Replies:** 4\ **Last updated:** [May 12, 2025, 11:46am UTC](https://calculix.discourse.group/t/convergence-issue-with-small-load/2737 "2025-05-12T11:46:14Z")
Greetings, I have a model of a nozzle in a cylinder and I am having convergence problems when I run the model in ccx2.20 with an elastic-plastic material model and NLGEOM=YES. It is strange because the load is so small.… --- ## [BEAM32R - Strange internal energy values](https://calculix.discourse.group/t/beam32r-strange-internal-energy-values/2731)
**Author:** [@cellini](https://calculix.discourse.group/u/cellini)\ **Replies:** 20\ **Last updated:** [May 9, 2025, 2:26pm UTC](https://calculix.discourse.group/t/beam32r-strange-internal-energy-values/2731 "2025-05-09T14:26:18Z")
Hi everyone I am testing a beam structure under compressione and i am finding some issues in the internal energy extraction. I am performing a NL analysis and the internal energy measured for the elements is in a quite … --- ## [How to include damping in the second step of a two-step simulation (static → dynamic)?](https://calculix.discourse.group/t/how-to-include-damping-in-the-second-step-of-a-two-step-simulation-static-dynamic/2732)
**Author:** [@yhuang94](https://calculix.discourse.group/u/yhuang94)\ **Replies:** 21\ **Last updated:** [May 9, 2025, 11:38am UTC](https://calculix.discourse.group/t/how-to-include-damping-in-the-second-step-of-a-two-step-simulation-static-dynamic/2732 "2025-05-09T11:38:18Z")
Dear all, I’m running a two-step simulation in CalculiX, where: The first step is a static step (using \*STATIC), to establish initial deformation for boundary conditions. The second step is a dynamic step (using \*DYNA… --- ## [Why does CalculiX convert very large initial temperatures into negative numbers?](https://calculix.discourse.group/t/why-does-calculix-convert-very-large-initial-temperatures-into-negative-numbers/2707)
**Author:** [@reio205](https://calculix.discourse.group/u/reio205)\ **Replies:** 13\ **Last updated:** [May 7, 2025, 11:23am UTC](https://calculix.discourse.group/t/why-does-calculix-convert-very-large-initial-temperatures-into-negative-numbers/2707 "2025-05-07T11:23:10Z")
I’m using the following input: \*INITIAL CONDITIONS, TYPE=TEMPERATURE Nall, 20 20258,3000 20259,3000 20260,3000 20261,3000 However, when I check the .dat file and view the results in ParaView, the temperatures are … --- ## [How to use the \*Restart command in my case?](https://calculix.discourse.group/t/how-to-use-the-restart-command-in-my-case/2728)
**Author:** [@reio205](https://calculix.discourse.group/u/reio205)\ **Replies:** 6\ **Last updated:** [May 6, 2025, 4:28pm UTC](https://calculix.discourse.group/t/how-to-use-the-restart-command-in-my-case/2728 "2025-05-06T16:28:17Z")
I have a layered part. In the first .inp, a coupled analysis of layer 1 is performed, injecting heat into layer 1, causing deformations. I want the second .inp to import the temperatures and deformations from the first… --- ## [Homebrew packages for ccx and cgx for macOS](https://calculix.discourse.group/t/homebrew-packages-for-ccx-and-cgx-for-macos/2729)
**Author:** [@Durbul](https://calculix.discourse.group/u/Durbul)\ **Replies:** 1\ **Last updated:** [May 6, 2025, 10:44am UTC](https://calculix.discourse.group/t/homebrew-packages-for-ccx-and-cgx-for-macos/2729 "2025-05-06T10:44:19Z")
For all macOS users, building current versions (2.22) of CalculiX CrunchiX (ccx) and CalculiX GraphiX (cgx) should now be much easier with the homebrew formulae provided by: Some notes: calculix-ccx comes with a mult… --- ## [CFLUX boundary conditions](https://calculix.discourse.group/t/cflux-boundary-conditions/2724)
**Author:** [@FranSordoni](https://calculix.discourse.group/u/FranSordoni)\ **Replies:** 4\ **Last updated:** [April 29, 2025, 7:04am UTC](https://calculix.discourse.group/t/cflux-boundary-conditions/2724 "2025-04-29T07:04:08Z")
Hello, I am trying to apply concentrated heat flux as a boundary condition but when I check the results, the nodes to which I impose a heat flux, have a different one. I have only applied boundary conditions of that nat… --- ## [Better Tetra4(C3D4) to Tetra10(C3D10) converter tool?](https://calculix.discourse.group/t/better-tetra4-c3d4-to-tetra10-c3d10-converter-tool/2708)
**Author:** [@leonstudio](https://calculix.discourse.group/u/leonstudio)\ **Replies:** 11\ **Last updated:** [April 28, 2025, 2:14am UTC](https://calculix.discourse.group/t/better-tetra4-c3d4-to-tetra10-c3d10-converter-tool/2708 "2025-04-28T02:14:27Z")
Hi, everyone! Does anybody have or know a tool that can convert C3D4 element to C3D10 in the format of calculix or abaqus inp file? I have wroten a fortran program that can work correctly, but the performance is worse, i… --- ## [Error with shell elements: a minimal example](https://calculix.discourse.group/t/error-with-shell-elements-a-minimal-example/2721)
**Author:** [@hconel](https://calculix.discourse.group/u/hconel)\ **Replies:** 4\ **Last updated:** [April 27, 2025, 8:52pm UTC](https://calculix.discourse.group/t/error-with-shell-elements-a-minimal-example/2721 "2025-04-27T20:52:33Z")
Hi, I am a CFD & finite volume guy, and a new CalculiX user (and new to FEM in general). My problem will probably sound very silly, but I couldn’t manage to solve it, so I’d appreciate any help. I am trying to understa… --- ## [Using \*Model Change ADD or REMOVE Elements for 3D Printing Simulation](https://calculix.discourse.group/t/using-model-change-add-or-remove-elements-for-3d-printing-simulation/1923)
**Author:** [@Arjun](https://calculix.discourse.group/u/Arjun)\ **Replies:** 23\ **Last updated:** [April 25, 2025, 11:48am UTC](https://calculix.discourse.group/t/using-model-change-add-or-remove-elements-for-3d-printing-simulation/1923 "2025-04-25T11:48:50Z")
Hello, I’m currently trying to convert Abaqus additive manufacturing simulations into CalculiX. Everything worked out great except for the dynamic addition and removal of elements. I looked in the CCX manual and tried i… --- ## [Temperature Handling After \*MODEL CHANGE, REMOVE in CalculiX](https://calculix.discourse.group/t/temperature-handling-after-model-change-remove-in-calculix/2713)
**Author:** [@Arjun](https://calculix.discourse.group/u/Arjun)\ **Replies:** 0\ **Last updated:** [April 24, 2025, 8:33pm UTC](https://calculix.discourse.group/t/temperature-handling-after-model-change-remove-in-calculix/2713 "2025-04-24T20:33:01Z")
When using \*MODEL CHANGE, REMOVE in CalculiX, I noticed that the temperature of the removed elements defaults to 0. Is there a way to retain the last specified temperature or revert to the predefined temperature value fo… --- ## [Is it possible to reverse a binary input file?](https://calculix.discourse.group/t/is-it-possible-to-reverse-a-binary-input-file/2700)
**Author:** [@PGA](https://calculix.discourse.group/u/PGA)\ **Replies:** 1\ **Last updated:** [April 22, 2025, 9:26pm UTC](https://calculix.discourse.group/t/is-it-possible-to-reverse-a-binary-input-file/2700 "2025-04-22T21:26:50Z")
Hi, I got an input file from some repository but it is binary one, I would like to understand that input file, how can I make it readable? --- ## [A puzzling result](https://calculix.discourse.group/t/a-puzzling-result/2196)
**Author:** [@chep](https://calculix.discourse.group/u/chep)\ **Replies:** 9\ **Last updated:** [April 22, 2025, 9:01pm UTC](https://calculix.discourse.group/t/a-puzzling-result/2196 "2025-04-22T21:01:38Z")
Hi all, A question for those more experienced than I… (Running ccx\_static V2.21 on Windows) I have been running wing models under flight pressure loads using different element type combinations. Before I go into a l… --- ## [Publicly available references for the models behind CalculiX](https://calculix.discourse.group/t/publicly-available-references-for-the-models-behind-calculix/2692)
**Author:** [@nlesquoy](https://calculix.discourse.group/u/nlesquoy)\ **Replies:** 2\ **Last updated:** [April 22, 2025, 1:46pm UTC](https://calculix.discourse.group/t/publicly-available-references-for-the-models-behind-calculix/2692 "2025-04-22T13:46:12Z")
Hi, I an currently writing my master thesis and I want to describe in a paragraph the models used by CalculiX. Is there somewhere a reference, where the underlying models, equations and numerical methods are explained? … --- ## [Early step termination](https://calculix.discourse.group/t/early-step-termination/2690)
**Author:** [@PGA](https://calculix.discourse.group/u/PGA)\ **Replies:** 3\ **Last updated:** [April 22, 2025, 7:07am UTC](https://calculix.discourse.group/t/early-step-termination/2690 "2025-04-22T07:07:41Z")
Hi I am running a coupled temperature-displacement, I want to cool down the part, but I want to cut the step 2, if the temperature is near 200 degrees, is that option possible? it is not like a termination of the job, I … --- ## [Problem in running lpbf inp in calculix](https://calculix.discourse.group/t/problem-in-running-lpbf-inp-in-calculix/2666)
**Author:** [@maheshd](https://calculix.discourse.group/u/maheshd)\ **Replies:** 17\ **Last updated:** [April 16, 2025, 12:42pm UTC](https://calculix.discourse.group/t/problem-in-running-lpbf-inp-in-calculix/2666 "2025-04-16T12:42:47Z")
I’m working on a laser powder-based simulation. I successfully ran the simulation in Abaqus and generated an .inp file. I then modified the .inp file to make it compatible with CalculiX. While I resolved all errors, my s… --- ## [Flow Network model - missing some heat](https://calculix.discourse.group/t/flow-network-model-missing-some-heat/1360)
**Author:** [@JohnM](https://calculix.discourse.group/u/JohnM)\ **Replies:** 8\ **Last updated:** [April 16, 2025, 12:40pm UTC](https://calculix.discourse.group/t/flow-network-model-missing-some-heat/1360 "2025-04-16T12:40:42Z")
I have a test problem that uses heat transfer with a pipe flow network. There is no pressure drop calculation, only mass flow and capacitance are considered (test model below). The figure shows the issue. I apply a c… --- ## [Creating membrane elements](https://calculix.discourse.group/t/creating-membrane-elements/2686)
**Author:** [@nlesquoy](https://calculix.discourse.group/u/nlesquoy)\ **Replies:** 4\ **Last updated:** [April 16, 2025, 12:29pm UTC](https://calculix.discourse.group/t/creating-membrane-elements/2686 "2025-04-16T12:29:08Z")
Hi, I need to perform FSI simulations on a lid-driven cavity (here an example of the configuration). I use CalculiX to compute the structure part of the problem, preCICE for the coupling and an in-house code for the CFD… --- ## [Any improvement of linear tetrahedral element?](https://calculix.discourse.group/t/any-improvement-of-linear-tetrahedral-element/1516)
**Author:** [@xyont](https://calculix.discourse.group/u/xyont)\ **Replies:** 6\ **Last updated:** [March 3, 2023, 2:52pm UTC](https://calculix.discourse.group/t/any-improvement-of-linear-tetrahedral-element/1516 "2023-03-03T14:52:58Z")
hi all, is there any progress or improvement of linear tetrahedral element available out there for Abaqus/CalculiX? an example of user element. i read few of paper regarding to this topics. this can be large benefit fo… --- ## [Obtaining shell forces of US3 element](https://calculix.discourse.group/t/obtaining-shell-forces-of-us3-element/2238)
**Author:** [@xyont](https://calculix.discourse.group/u/xyont)\ **Replies:** 6\ **Last updated:** [April 10, 2025, 6:26am UTC](https://calculix.discourse.group/t/obtaining-shell-forces-of-us3-element/2238 "2025-04-10T06:26:15Z")
hi, for the purpose of designing concrete shell reinforcement required an output of membrane forces, moment and shear. It seems US3 only provide stress output display. Is there output of forces available directly, or som… --- ## [Help to correctly apply the constraints](https://calculix.discourse.group/t/help-to-correctly-apply-the-constraints/2679)
**Author:** [@reio205](https://calculix.discourse.group/u/reio205)\ **Replies:** 3\ **Last updated:** [April 9, 2025, 8:04pm UTC](https://calculix.discourse.group/t/help-to-correctly-apply-the-constraints/2679 "2025-04-09T20:04:41Z")
I want my analysis to generate a deformation similar to image two, but I haven’t been able to achieve it. I haven’t been able to correctly use the 3-2-1 analysis for the constraints. What can I do to ensure the deformat… --- ## [Best workflow for beginners](https://calculix.discourse.group/t/best-workflow-for-beginners/2060)
**Author:** [@Lt72884](https://calculix.discourse.group/u/Lt72884)\ **Replies:** 58\ **Last updated:** [April 9, 2025, 1:07pm UTC](https://calculix.discourse.group/t/best-workflow-for-beginners/2060 "2025-04-09T13:07:34Z")
I have been using freecad for some basic FEA. I am wanting to know what the best work flow for a beginner in FEA would be? IE All in freecad mesh the object in freecad, export, then use calculix model in freecad\>mes… --- ## [Error while removing prescribed displacement Boundary condition](https://calculix.discourse.group/t/error-while-removing-prescribed-displacement-boundary-condition/2656)
**Author:** [@kraviteja](https://calculix.discourse.group/u/kraviteja)\ **Replies:** 7\ **Last updated:** [April 7, 2025, 2:43pm UTC](https://calculix.discourse.group/t/error-while-removing-prescribed-displacement-boundary-condition/2656 "2025-04-07T14:43:07Z")
I am trying to simulate distortion in a cylinder. I started with a simple problem where I create a bulge in the cylinder using displacement boundary conditions. In the subsequent step, I remove the displacement boundary … --- ## [About run calculix with abaqus inp file](https://calculix.discourse.group/t/about-run-calculix-with-abaqus-inp-file/1078)
**Author:** [@Jey](https://calculix.discourse.group/u/Jey)\ **Replies:** 10\ **Last updated:** [April 17, 2022, 3:35pm UTC](https://calculix.discourse.group/t/about-run-calculix-with-abaqus-inp-file/1078 "2022-04-17T15:35:22Z")
Hello friends. Glad to meet you here! I Just started calculix and have lots of problems… Plz help me. I made inp file by abaqus and tried to run calculix with it. but its not working. error message is ’ What shou… --- ## [CFLUX Submodeling](https://calculix.discourse.group/t/cflux-submodeling/2659)
**Author:** [@FranSordoni](https://calculix.discourse.group/u/FranSordoni)\ **Replies:** 4\ **Last updated:** [April 2, 2025, 1:33pm UTC](https://calculix.discourse.group/t/cflux-submodeling/2659 "2025-04-02T13:33:55Z")
Hello, I am trying to apply the submodelling approach but defining the heat flux as boundary conditions. I know that I will have to modify the source code to add this possibility to the cflux card, but my question is re… --- ## [Copen abaqus/ccx](https://calculix.discourse.group/t/copen-abaqus-ccx/2657)
**Author:** [@Iacobellis88](https://calculix.discourse.group/u/Iacobellis88)\ **Replies:** 1\ **Last updated:** [April 2, 2025, 9:57am UTC](https://calculix.discourse.group/t/copen-abaqus-ccx/2657 "2025-04-02T09:57:59Z")
Hello everyone, I am doing a comparison with abaqus about COPEN. I noticed that abaqus by defaut uses hard contact, while in ccx hard contact does not exist. It is swapped in soft contact. So my question is: how can g… --- ## [CELS.Contact (Springs Energy)](https://calculix.discourse.group/t/cels-contact-springs-energy/2226)
**Author:** [@Disla](https://calculix.discourse.group/u/Disla)\ **Replies:** 5\ **Last updated:** [April 1, 2025, 11:09am UTC](https://calculix.discourse.group/t/cels-contact-springs-energy/2226 "2025-04-01T11:09:21Z")
Hi, I’m trying to extract how the stiffness across a contact is distributed depending on the mesh density. I have request \*CONTACT FILE CELS but for some reason the result is only shown at one node of the slave surface… --- ## [Different coupling constraints and their limitations](https://calculix.discourse.group/t/different-coupling-constraints-and-their-limitations/2586)
**Author:** [@Calc\_em](https://calculix.discourse.group/u/Calc_em)\ **Replies:** 4\ **Last updated:** [March 26, 2025, 2:04pm UTC](https://calculix.discourse.group/t/different-coupling-constraints-and-their-limitations/2586 "2025-03-26T14:04:29Z")
Since it can be quite confusing, I am creating this post to summarize the differences between coupling constraint types in CalculiX and to highlight their key limitations. Feel free to correct/add anything to this. ABAQ… --- ## [Acceleration output in dynamic calculations](https://calculix.discourse.group/t/acceleration-output-in-dynamic-calculations/2633)
**Author:** [@JuanP74](https://calculix.discourse.group/u/JuanP74)\ **Replies:** 2\ **Last updated:** [March 26, 2025, 1:51pm UTC](https://calculix.discourse.group/t/acceleration-output-in-dynamic-calculations/2633 "2025-03-26T13:51:33Z")
Hello, I’ve noticed that there is not acceleration output for dynamic calculations. What do you do if you need them? Numerical derivative of displacements/velocities…? Anyone has already addressed the issue? Regards --- ## [External solver comparison for nonlinear analysis of shell element](https://calculix.discourse.group/t/external-solver-comparison-for-nonlinear-analysis-of-shell-element/2615)
**Author:** [@xyont](https://calculix.discourse.group/u/xyont)\ **Replies:** 8\ **Last updated:** [March 25, 2025, 6:43pm UTC](https://calculix.discourse.group/t/external-solver-comparison-for-nonlinear-analysis-of-shell-element/2615 "2025-03-25T18:43:31Z")
hi, i successfully running several tests of thin-walled steel section in CalculiX with shell element. Analysis type is large deformation and material plasticity to detect buckling behavior, compression loads applied as d… [Previous page](https://calculix.discourse.group/c/uncategorized/1.md) [Next page](https://calculix.discourse.group/c/uncategorized/1.md?page=2)