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Error: Failed to Find a Solution. Returned Solution is Not Converged

Solution numéro: 964 Versions: Toutes les versions

I get this message: Failed to find a solution. The relative residual (0.28) is greater than the relative tolerance. Returned solution is not converged. Messages similar to this are returned for nonlinear problems ...

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Avoiding Negative Concentrations

Solution numéro: 952 Se réfère à: CFD Module, Chemical Reaction Engineering Module, COMSOL Multiphysics, Corrosion Module, Electrochemistry Module, Electrodeposition Module, Microfluidics Module, Mixer Module, Subsurface Flow Module Versions: Toutes les versions

Why do I get negative values of the concentration in my diffusion, convection and reaction model? Why do I see values that go below, or above, their lowest, or highest, possible values based upon the boundary ...

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What Does Degrees of Freedom (DOFs) Mean in COMSOL Multiphysics?

Solution numéro: 875 Versions: Toutes les versions

What does degrees of freedom (DOFs) mean in COMSOL Multiphysics? The solution time and memory requirements are strongly related to the number of degrees of freedom in the model. It is often desirable to be able to ...

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Modeling of Step Transitions

Solution numéro: 905 Versions: Toutes les versions

You may want to define loads, material properties, or boundary conditions that vary abruptly with respect to the solution, or with respect to time. This can, however, lead to a solution which is discontinuous in space ...

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Handling Large Models

Solution numéro: 830 Versions: Toutes les versions

Models with many domains, boundaries, and physics features are slow to work with. Large models can contain hundreds or even thousands of domains, boundaries, and physics features. Such a large number of features ...

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