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Temperature of the wall

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Old   March 30, 2016, 06:54
Default Temperature of the wall
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Hello!

How could it be that maximum and minimum values of temperature given by a contour (local range) in CFD-Post do not correspond to the values given by a function calculator (CFD-Post) or volume integrals (Fluent). Look to a picture.
Picture is in my album.
http://www.cfd-online.com/Forums/mem...mperature.html
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Old   March 30, 2016, 18:12
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The picture in your album is difficult to read, try posting a higher resolution image. What maximum and minimum temperature values are you getting, are they significantly different or within interpolation errors?
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Old   March 31, 2016, 09:12
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Thank you for reply!

The difference between minimum or maximum values on a contour and minimum or maximum values given by the volume integrals are significant (about 100 degrees).
Minimum temperature value given by contour is 592 C, but by volume integral is 723 C.
Max. from contour is 909 C, but from volume integral is 887 C.
The task is non-premixed combustion CH4 in Air. Gradients of pressure and temperature are very large. May be strange avereging of the node-values? May be not converged?
But it is very difficult to reach convergence because of large pressure gradients on air and fuel inlets. The temperature may differ significantly from one iteration to another.
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Old   April 4, 2016, 17:42
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Are you sure the results have been updated from Fluent to CFD-Post? Are there multiple phases and/or multiple domains which may or may not be included in the calculations? If both software packages are reading the same data set and definitely giving different results then it must be with the methods of calculating the ranges.

Perhaps apply the same custom range to both plots and visually inspect the plots. If these figures are similar and only the minimum value is significantly off then where is that occurring? Have you tried mesh refinement?
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Old   April 5, 2016, 11:43
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Quote:
Originally Posted by `e` View Post
Are you sure the results have been updated from Fluent to CFD-Post? Are there multiple phases and/or multiple domains which may or may not be included in the calculations? If both software packages are reading the same data set and definitely giving different results then it must be with the methods of calculating the ranges.

Perhaps apply the same custom range to both plots and visually inspect the plots. If these figures are similar and only the minimum value is significantly off then where is that occurring? Have you tried mesh refinement?
Contours in fluent GUI and in CFD-Post are the same, but values (min and max), given by the volume integrals (function calculator) are different from that values on the contours.
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