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ocy February 21, 2005 05:19

Fluid not heating up
 
Hi all,

I am Modeling a 2D chimney.

I have a solid heat source(0.4m x 2m) at the base of my chimney(1m x 50m). The rest of the chimney is consist of air(fluid zone)

I set energy source term for my solid with a heat generation rate of 1000w/m^3.

However, When i iterate, only the solid zone heats up. The fluid zone remains at ambient temp.

Can anyone help? Thanks

Venugopal February 21, 2005 22:00

Re: Fluid not heating up
 
hi, 1000w is not sufficient to heat the air. You can check in another way also. Give a low thermal conductivity to the air or you can increase the heat generation rate in heat source. If you are finding any temp difference in the air, then you approach is correct, otherwise you are not going in correct path.

Venu Gopal. S

ocy February 22, 2005 04:16

Re: Fluid not heating up
 
Hi Venu Gopal,

Thanks for your help. I increased my heat source to 1e+10 w/m^3. The fluid gets heated up.

When i removed the insulation at the wall, the temp at the wall drops as expected. However, the temp of the fluid at the interior is not affected much. The temp is still v high.

How could this be so??

Pls help. Thanks in advance.

Regards, ocy

Venugopal February 22, 2005 20:46

Re: Fluid not heating up
 
The temp. of the fluid should increase, because the walls are very high, all fluid temperature might be at uniform. Tell me your problem clearly.

Venu Gopal

ocy February 24, 2005 03:43

Re: Fluid not heating up
 
Hi Venugopal,

When i remove the insulation of the wall, The temp of the flow inside the chimney remains very high. Only a small region near the wall show a decrease in temp.

Is this expected? Or have i done something wrong?

Thks


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