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Old   July 28, 2009, 23:29
Question Natural Convection
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Maryam Kia shemshaki
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i want simulation natural convection loop by FLUENT but i have some problem.
my result depend on intitial value?!!!
What do i?
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Old   July 29, 2009, 10:28
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zhangming
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Did you Set air density to be constant?
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Old   July 30, 2009, 03:16
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Maryam Kia shemshaki
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working fluid is water & i use Boussinesq approximation for density
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Old   July 30, 2009, 15:26
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Chris
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What do you mean when you say that your result depends on your initial value? Do you mean that you get a different result if you initialize your solution with different values for velocity?
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Old   August 1, 2009, 00:56
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Maryam Kia shemshaki
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yes, if i put 300K for initial temperature i get in result (in temperature contour) 300k and if i put 320K for it i get 320
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Old   August 1, 2009, 14:44
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Have you checked the section in the FLUENT manual about natural convection to see if you have setup your simulation correctly? From what you are saying, it sounds like the temperature everywhere in the flow field is the same, meaning that there is probably something wrong with your setup. If in fact that's not what you're saying, could you please provide more information about your problem?
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Old   August 2, 2009, 03:32
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Maryam Kia shemshaki
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i'm working in natural convection loop.
The heat sink is located at an elevation higher than the source. That causes the circulating fluid, heated from bottom and cooled
from top, to flow under the influence of gravity, the difference
in fluid density between the two vertical arms being the driving
force.
heater(heat source) expose constant thermal flux and cooler(heat sink) exposed costant temperature.working fluid is water.
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Old   August 4, 2009, 23:26
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is there anyone?
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