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High index DAE problem

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Is it possible to solve high index DAE problems using COMSOL??

I am trying to solve a simple 2nd order differential equation. I see that the profile does not satisfy the initial values given.

I have attached my comsol model file while the expected result that I got using another software is also attached.

Any help is appreciated

Thank you
Vishnu


2 Replies Last Post Aug 10, 2016, 7:35 p.m. EDT
Jeff Hiller COMSOL Employee

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Posted: 8 years ago Aug 10, 2016, 6:09 p.m. EDT
Hello Vishnu,
Without looking at your mph file, it looks like a classic case of imposing BCs that are inconsistent with initial conditions. You will find several threads on the Discussion Forum where this is discussed, including this one: www.comsol.com/community/forums/general/thread/32944 .
Best,
Jeff
Hello Vishnu, Without looking at your mph file, it looks like a classic case of imposing BCs that are inconsistent with initial conditions. You will find several threads on the Discussion Forum where this is discussed, including this one: https://www.comsol.com/community/forums/general/thread/32944 . Best, Jeff

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Posted: 8 years ago Aug 10, 2016, 7:35 p.m. EDT
Hi Jeff

Yes the step function did the trick.

Thank you
Vishnu
Hi Jeff Yes the step function did the trick. Thank you Vishnu

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