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I have a large, complicated, model that is not solving, or taking a long time to solve. What should I do? There are a number of reasons why a model may not be solving, or solving very slowly. This article describes...
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When running running a model that uses the MUMPS solver repeatedly on my multicore processor, I notice a small gradual increase in Memory Consumption. Please make sure that your COMSOL Multiphysics 5.4 installation is...
Version: 5.4 - Platform: Windows, Linux

When running large models on a cluster with COMSOL Multiphysics 5.4, the MUMPS solver hangs or crashes. This issue has been fixed in Update 4 for COMSOL Multiphysics 5.4. Please update your COMSOL installation to...
Version: 5.4 - Platform: Windows, Linux

Transient models involve computing a solution that varies over time. To do so, the software begins with the given initial conditions and computes the evolution of the unknowns using one of several different...
Version: All versions - Platform: All Platforms

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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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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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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