Support Knowledge Base

How do I gain confidence in the accuracy of the solution to my problem? How do I perform a mesh refinement study? All of the numerical methods used within COMSOL Multiphysics® discretize the modeling space via a Mesh...
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I am solving a linear stationary finite element model but the software is not solving. Why? What can I do about this? A linear finite element model is one in which all of the material properties, loads, boundary...
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I would like to define my own customized coupling between two existing physics interfaces. How can I do this? How can I find the names of the variables that I will need to use? The ability to define arbitrary, and...
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How, and why, switch between a fully coupled and a segregated approach to solving a multiphysics model? How, and why, switch between the direct and iterative linear system solver? Fully Coupled versus Segregated...
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I am solving a Multiphysics problem involving electromagnetics and heat transfer. The electromagnetic fields are varying at a constant frequency, and the period is very short compared to the timespan over which the...
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After exporting a glTF-file from my COMSOL Multiphysics model, I get an error message when I try to open it in an external viewer. The most probable cause for this issue is that the external glTF-file you are using...
Version: 5.4 - Platform: All Platforms

My models contain a lot of solution data, and I do not want my file sizes to get too large, it takes a lot of disk space. What can I do to reduce file size? Will this reduce the time it takes to solve the model? File...
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I am solving a transient model and changed the stepsize in the Times: field in the Study Settings, but the solver is still taking exactly the same timesteps. It seems the timesteps that the solver is taking are not...
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When using a three-server redundancy setup for hosting the license manager, license handling does not work correctly if the designated Primary server goes down. To work around this, make sure that the license manager...
Version: 5.3,5.3a,5.4 - Platform: All Platforms

In COMSOL Multiphysics 5.4, I receive some or all of the following error messages: The license could not be validated No such feature exists Feature: SERIAL License Path: C:\...\license.dat FlexNet licensing...
Version: 5.4 - Platform: