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ill-conditioned stiffness matrix

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Hello all,

I am trying to extract model matrixes using COMSOL and designing my own nonlinear dynamic solver in Matlab. However, I have convergence issues.

Then I check the condition number of stiffness matrix Ke using matlab command condest(), it returns values between 1e12 to 1e14.

du = Ke\Le, an ill-conditioned Ke will weaken the accuracy of du. Does COMSOL/matlab handle matrix inversion accurately when its condition number is above 1e12? Are there any methods to tackle this issue?

Thanks a lot

1 Reply Last Post 15 giu 2014, 06:29 GMT-4
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Posted: 1 decade ago 15 giu 2014, 06:29 GMT-4
Hi, Did you find any solution ? I am also facing more or less similar issue.
Hi, Did you find any solution ? I am also facing more or less similar issue.

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