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Initial values error using mapped mesh

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Hello,

Every time I try to use a mapped mesh for a time dependent simulation I have the following error :
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The following feature has encountered a problem :
failed to find consistent initial values.
System matrix is zero.
Last time step is not converged...
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It is weird because when I run the same simulation with a mesh generated by default, everything works fine.
My geometry is more or less a rectangle (3D).

Is there anything special to do with the initial condition when a mapped mesh is used ? I don't find anything on the web.

Thank you for your help.

1 Reply Last Post 1 mag 2013, 02:04 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 1 mag 2013, 02:04 GMT-4
Hi

there are no general rule here, and you do not say much about your model, stationary or probably time dependent, initial conditions, the local gradients of your dependent variables , mesh density ...

often the mesh density, diffusivity and time stepping are related, which means that for diffusion equations, where you have initial step or very steep gradients you might have convergence issues

But we cannot guess out here, from what you tell about your model ;)

--
Good luck
Ivar
Hi there are no general rule here, and you do not say much about your model, stationary or probably time dependent, initial conditions, the local gradients of your dependent variables , mesh density ... often the mesh density, diffusivity and time stepping are related, which means that for diffusion equations, where you have initial step or very steep gradients you might have convergence issues But we cannot guess out here, from what you tell about your model ;) -- Good luck Ivar

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