Natural Convection
 

i want simulation natural convection loop by FLUENT but i have some problem.
my result depend on intitial value?!!!:(
What do i?

Did you Set air density to be constant?

working fluid is water & i use Boussinesq approximation for density:confused:

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?

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:eek:

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?

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.

is there anyone?