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convergence problem

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Hi, I am a newcomer to comsol.

Here is my problem. I always meet too large convergence when I run the comsol. If i change something to fix convergence, the reaction rate will be very low and the model still can not work.

can anyone help me to solve this problem? Thanks.

3 Replies Last Post 2013年8月6日 GMT-4 08:18

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Posted: 1 decade ago 2010年9月28日 GMT-4 04:18
Reading your question I only understand that you have problem running your model. It would be more helpful if you post useful amount of details and if possible upload your model. Then we can help you much more effectively.
Reading your question I only understand that you have problem running your model. It would be more helpful if you post useful amount of details and if possible upload your model. Then we can help you much more effectively.

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Posted: 1 decade ago 2010年9月28日 GMT-4 15:06

Reading your question I only understand that you have problem running your model. It would be more helpful if you post useful amount of details and if possible upload your model. Then we can help you much more effectively.


I am sorry for my confusing question.

I wanna ignite the reactant so it can react further. When I set the ignition heat source = 5e6 Kw/m^2 and the ignition time = 1.5s, and choose nonlinear solver to solve this problem. however, it stops at time = 1.08 and can not solve further. how can i fix this problem? should change my solver parameters or do something else.

Thanks.
[QUOTE] Reading your question I only understand that you have problem running your model. It would be more helpful if you post useful amount of details and if possible upload your model. Then we can help you much more effectively. [/QUOTE] I am sorry for my confusing question. I wanna ignite the reactant so it can react further. When I set the ignition heat source = 5e6 Kw/m^2 and the ignition time = 1.5s, and choose nonlinear solver to solve this problem. however, it stops at time = 1.08 and can not solve further. how can i fix this problem? should change my solver parameters or do something else. Thanks.

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Posted: 1 decade ago 2013年8月6日 GMT-4 08:18
Hi Yishan,

I am wondering to know where you introduced the ignition heat source and the ignition time?
I want to introduce an ignition heat source. I am using the Reaction engineering (re) physics and the only place for introducing a heat source is on the 'Energy Balance' node. Did you also introduced your ignition source in this node?

Best,
Zari
Hi Yishan, I am wondering to know where you introduced the ignition heat source and the ignition time? I want to introduce an ignition heat source. I am using the Reaction engineering (re) physics and the only place for introducing a heat source is on the 'Energy Balance' node. Did you also introduced your ignition source in this node? Best, Zari

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