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Failed to evaluate variable jacobian!..

Posted 25 mar 2011, 08:27 GMT-4 Fluid & Heat, Heat Transfer & Phase Change Version 4.3 5 Replies

Atilla Savas
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Hi everybody,

I want to simulate a heat transfer and navier stokes problem. I have two subdomains. In one of the subdomains only the heat transfer equation is solved, not the navier stokes equation.

To implement this condition I uncheck the tick of the navier stokes application mode "valid in this subdomain"

But I encounter and error error 6250 "Failed to evaluate variable jacobien" variable u subdomain....

I cannot find anything about the error code 6250..

What could be the problem?

How can I solve this problem?

atilla savas
5 Replies Last Post 25 gen 2015, 14:46 GMT-5
Xiaogai Li
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Posted: 1 decade ago 25 mar 2011, 10:39 GMT-4
Hi,

Is "u" the name of the variable for Navier stokes module?
Do you have coupling between heat transfor and Navier Stoke modules in the model?

If it is, then I guess one possible reason might be you didn't solve the Navier stokes equation on subdomain, but you used the solution of Navier stokes equation (say u) coupling in the heat transfer module.

XLi
Hi, Is "u" the name of the variable for Navier stokes module? Do you have coupling between heat transfor and Navier Stoke modules in the model? If it is, then I guess one possible reason might be you didn't solve the Navier stokes equation on subdomain, but you used the solution of Navier stokes equation (say u) coupling in the heat transfer module. XLi
Atilla Savas
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Posted: 1 decade ago 25 mar 2011, 13:40 GMT-4
Thank you Xli,

I solved the problem, there was a convective term including velocity u value, when I set it to zero, it is ok now.

atilla
Thank you Xli, I solved the problem, there was a convective term including velocity u value, when I set it to zero, it is ok now. atilla
Umar Zeeshan
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Posted: 1 decade ago 26 lug 2012, 09:02 GMT-4
Hallo.
hey guys..

I have the same problem.
Error is faild to evaluate variable jacobain,
I'm trying to coule the Electromagnetic with Non-isothermal Heating, for heating the water with microwaves.
any Idea how to solve it.
I attach the problem Pics in attach file.

Shall be very thankful to all

Bye
Umar
Hallo. hey guys.. I have the same problem. Error is faild to evaluate variable jacobain, I'm trying to coule the Electromagnetic with Non-isothermal Heating, for heating the water with microwaves. any Idea how to solve it. I attach the problem Pics in attach file. Shall be very thankful to all Bye Umar

Attachments:

Philip David Flammer
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Posted: 1 decade ago 24 ott 2014, 16:50 GMT-4
For those who look at this later, it happens sometimes because one physics is trying to access a variable from another physics that is not activated in that domain.
For those who look at this later, it happens sometimes because one physics is trying to access a variable from another physics that is not activated in that domain.
Gongda Lu
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Posted: 10 years ago 25 gen 2015, 14:46 GMT-5
Philip is exactly right, at least it solved my problem. I was totally unaware that the variable definition has been somehow deactivated on the domain.
Philip is exactly right, at least it solved my problem. I was totally unaware that the variable definition has been somehow deactivated on the domain.

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