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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 6 ago 2013, 08:18 GMT-4

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Posted: 1 decade ago 28 set 2010, 04:18 GMT-4
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 28 set 2010, 15:06 GMT-4

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 6 ago 2013, 08:18 GMT-4
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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