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Change material problem

Abdulrahman Al Rumaidh

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Hi,

I am a facing a strange problem. I compiled a model that studies conjugate heat transfer between STEEL and WATER and It worked nicely. However, I wanted to investigate what will happen if AIR was used instead of WATER. I got the following error:

Undefined value found.
- Detail: Undefined value found in the equation residual vector.
There are 380 degrees of freedom giving NaN/Inf in the vector for the variable comp1.yPlus.
at coordinates: (-0.127373,-0.405955,-0.026), (-0.128064,-0.407019,-0.0223525), (-0.128768,-0.408103,-0.0178567), (0.065109,-0.424149,-0.112772), (0.0594724,-0.427098,-0.111054), ...

I read that this error shows up if not enough boundaries were set. But it worked with water. So, why didn't it work with air?

Regards,

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Abdulrahman Al Rumaidh
Mechanical Engineering Student | University of Bahrain

1 Reply Last Post 28 dic 2015, 12:03 GMT-5
Abdulrahman Al Rumaidh

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Posted: 9 years ago 28 dic 2015, 12:03 GMT-5
I tried to go gradually in increasing the inlet velocity until reaching the desired one. Each time I solved a step, I set its solution as the initialization of the next step. It works but consumes time. This is a workaround, any ideas for tackling this problem properly?

--
Abdulrahman Al Rumaidh
Mechanical Engineering Student | University of Bahrain
I tried to go gradually in increasing the inlet velocity until reaching the desired one. Each time I solved a step, I set its solution as the initialization of the next step. It works but consumes time. This is a workaround, any ideas for tackling this problem properly? -- Abdulrahman Al Rumaidh Mechanical Engineering Student | University of Bahrain

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