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De-icing of wing

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Hi,
I'm doing simulation of deicing of wing due to heating up sections of the leading edge of the wing. However, when I go through all the boundary set up and run the solution. I get an error:

Undefined value found.
- Detail: NaN or Inf found when solving linear system using SOR.

I've attached my file to this, please help me eliminate this if possible. Few possibilities of error might be at how my velocity is set up: i want it in -y direction but I'm not sure if that will cause any problems or not.


3 Replies Last Post 8 mai 2013, 18:27 UTC−4

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Posted: 1 decade ago 5 mai 2013, 14:31 UTC−4
Update: I've managed to run on upto 200k Q which gives me 5 degree increase in temperature. However, If i continue to increase Q, the simulation keeps giving that NAN error.
Update: I've managed to run on upto 200k Q which gives me 5 degree increase in temperature. However, If i continue to increase Q, the simulation keeps giving that NAN error.

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 7 mai 2013, 02:35 UTC−4
Hi

you could try to map your metal layer with at least two elements in the thickness, and then more serious, I do not believe you are in truly laminar flow at that air velocity, which means among other you need a finer mesh, furthermore, heating with 1[MW]/(0.6[m^3]) seems very high, but it might be correct, but you will get quite some local gradients, hence you need a fine mesh on the solid air face

--
Good luck
Ivar
Hi you could try to map your metal layer with at least two elements in the thickness, and then more serious, I do not believe you are in truly laminar flow at that air velocity, which means among other you need a finer mesh, furthermore, heating with 1[MW]/(0.6[m^3]) seems very high, but it might be correct, but you will get quite some local gradients, hence you need a fine mesh on the solid air face -- Good luck Ivar

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Posted: 1 decade ago 8 mai 2013, 18:27 UTC−4

Hi

you could try to map your metal layer with at least two elements in the thickness, and then more serious, I do not believe you are in truly laminar flow at that air velocity, which means among other you need a finer mesh, furthermore, heating with 1[MW]/(0.6[m^3]) seems very high, but it might be correct, but you will get quite some local gradients, hence you need a fine mesh on the solid air face

--
Good luck
Ivar


Thanks for the reply. I will attempt to fine the mesh as much as possible, however I'm working on a laptop so I might not be able to do so.

I do have additional questions. Is it possible to obtain the heating of the leading edge by some other boundary condition than the heat source? Right now I'm specifying the temperature at the bottom of the leading edge and that is giving expected results. However, I want to be able to do it in some sort of q value at the boundary condition.
[QUOTE] Hi you could try to map your metal layer with at least two elements in the thickness, and then more serious, I do not believe you are in truly laminar flow at that air velocity, which means among other you need a finer mesh, furthermore, heating with 1[MW]/(0.6[m^3]) seems very high, but it might be correct, but you will get quite some local gradients, hence you need a fine mesh on the solid air face -- Good luck Ivar [/QUOTE] Thanks for the reply. I will attempt to fine the mesh as much as possible, however I'm working on a laptop so I might not be able to do so. I do have additional questions. Is it possible to obtain the heating of the leading edge by some other boundary condition than the heat source? Right now I'm specifying the temperature at the bottom of the leading edge and that is giving expected results. However, I want to be able to do it in some sort of q value at the boundary condition.

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