Simulate heat transfer of heat sink in a box...

chien87 · November 6, 2009, 11:21

Hi all CFD EXPERTS,
I am newbie for cfd, currently using ansys11.0, my situation is there is a box with 2 inlets (side) for air flow in and 1 inlet for air flow out (top), the heat sink is put at the base and middle of the box, the heat source is placed below the heat sink. I need to compare the performance of various heat sink through natural air. However, I just know to set the basic thgs such as inlet and outlet..
The 2 inlets velocity i set for the box is 1m/s, outlet i set to 0 relative pressure.The default of the domain is fluid fluid domain which is the heat source. For my case, i thk my default domain should solidfluid domain, can i change the default?? Or is my region gt prob??

Since , i try many times also fail to change the default, i create another domain for the solid fluid. I run the analysis, the simulation success, bt the graph of the result i din understand. Anyone can tell me can go where to understand the graph ??

When post the result, the flow of the air din show out... my supervisor say is time scale problems..bt i try to increase the time scare, the flow also din show out..

This is my final year project, bt tis software nvr teach in cls.. So i blur v it..anyone can teach me how to solve tis ??

Can teach me solve the domain problem??

Any suggestion can giv me to improve the simulation??

pls help me...

mvoss · November 6, 2009, 11:53

hi,
could you post a scheme of your problem? i didn´t get it. Solid Fluid??
I suppose you have a room with to inlets for air and one pressure outlet/openning AND an energy source in a solid domain at the ground of the solid domain. Are you interested in the temperature of the solid? If not, you could simplify your setup and just add a source at the former solid/fluid-interface.

And which "graph" is it that you didn't understand?
neewbie

chien87 · November 6, 2009, 12:25

Quote:

Originally Posted by neewbie

hi,
could you post a scheme of your problem? i didn´t get it. Solid Fluid??
I suppose you have a room with to inlets for air and one pressure outlet/openning AND an energy source in a solid domain at the ground of the solid domain. Are you interested in the temperature of the solid? If not, you could simplify your setup and just add a source at the former solid/fluid-interface.

And which "graph" is it that you didn't understand?
neewbie

Yaya, my situation is like tat.. the heat source is electronic components..
i wan to know hw efficiency the heat sink can transfer d heat if in a room like that...

chien87 · November 6, 2009, 12:47

1st photo is my model.. The fluid fluid domain shown at the heat sink base... another rectangular box below heat sink is the heat source..

2nd photo is the graph i mean..

Dun knw why, got heat transfer 1 n 2..momentum 1 n2 , turbulence 1 n 2... i set wrong thg??
all tis graph i din understand...wat is meaning if the heat transfer graph like that??

ghorrocks · November 7, 2009, 06:39

It looks like you are solving the fluid equations in both domains. If I understand you correctly you will need to set your heatsink to a solid domain.

chien87 · November 7, 2009, 07:02

Quote:

Originally Posted by ghorrocks

It looks like you are solving the fluid equations in both domains. If I understand you correctly you will need to set your heatsink to a solid domain.

y should set it into solid domain?? can u explain bit to me??

ghorrocks · November 7, 2009, 07:04

You are doing a Conjugate Heat Transfer (CHT) simulation, see the heating coil tutorial for how to set them up.

chien87 · November 7, 2009, 07:11

The tutorial i done many times d.. I still not familiar to set the domain, subdomain and domain interface.. That y i ask experts here..

Summore tis simulation have 1 heat source below d heat sink... heat source n heat sink contact... hw the set that the heat source transfer heat to heat sink?? and the heat sink dissapate the heat to air???

lyes43 · February 8, 2011, 04:50

Quote:

Originally Posted by chien87

Yaya, my situation is like tat.. the heat source is electronic components..
i wan to know hw efficiency the heat sink can transfer d heat if in a room like that...

hey I'm workig on simulate the mixed convection in a rectangular horizontal channel were there are heat sources (ex electronic compounents) mayb u help me to simulate that problem using any code or program
I havethe experimental results to valid my reult
saiting ur answer thx. lyes43@yahoo.com

November 6, 2009, 11:21	Simulate heat transfer of heat sink in a box...	#1
chien87 New Member Lim Wah Chien Join Date: Nov 2009 Posts: 5 Rep Power: 17	Hi all CFD EXPERTS, I am newbie for cfd, currently using ansys11.0, my situation is there is a box with 2 inlets (side) for air flow in and 1 inlet for air flow out (top), the heat sink is put at the base and middle of the box, the heat source is placed below the heat sink. I need to compare the performance of various heat sink through natural air. However, I just know to set the basic thgs such as inlet and outlet.. The 2 inlets velocity i set for the box is 1m/s, outlet i set to 0 relative pressure.The default of the domain is fluid fluid domain which is the heat source. For my case, i thk my default domain should solidfluid domain, can i change the default?? Or is my region gt prob?? Since , i try many times also fail to change the default, i create another domain for the solid fluid. I run the analysis, the simulation success, bt the graph of the result i din understand. Anyone can tell me can go where to understand the graph ?? When post the result, the flow of the air din show out... my supervisor say is time scale problems..bt i try to increase the time scare, the flow also din show out.. This is my final year project, bt tis software nvr teach in cls.. So i blur v it..anyone can teach me how to solve tis ?? Can teach me solve the domain problem?? Any suggestion can giv me to improve the simulation?? pls help me... notavishal likes this.

November 7, 2009, 07:11		#8
chien87 New Member Lim Wah Chien Join Date: Nov 2009 Posts: 5 Rep Power: 17	The tutorial i done many times d.. I still not familiar to set the domain, subdomain and domain interface.. That y i ask experts here.. Summore tis simulation have 1 heat source below d heat sink... heat source n heat sink contact... hw the set that the heat source transfer heat to heat sink?? and the heat sink dissapate the heat to air??? Last edited by chien87; November 7, 2009 at 07:41.

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November 6, 2009, 11:53		#2
mvoss Senior Member Matthias Voß Join Date: Mar 2009 Location: Berlin, Germany Posts: 449 Rep Power: 20	hi, could you post a scheme of your problem? i didn´t get it. Solid Fluid?? I suppose you have a room with to inlets for air and one pressure outlet/openning AND an energy source in a solid domain at the ground of the solid domain. Are you interested in the temperature of the solid? If not, you could simplify your setup and just add a source at the former solid/fluid-interface. And which "graph" is it that you didn't understand? neewbie

November 6, 2009, 12:47		#4
chien87 New Member Lim Wah Chien Join Date: Nov 2009 Posts: 5 Rep Power: 17	1st photo is my model.. The fluid fluid domain shown at the heat sink base... another rectangular box below heat sink is the heat source.. 2nd photo is the graph i mean.. Dun knw why, got heat transfer 1 n 2..momentum 1 n2 , turbulence 1 n 2... i set wrong thg?? all tis graph i din understand...wat is meaning if the heat transfer graph like that??

November 7, 2009, 06:39		#5
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,854 Rep Power: 144	It looks like you are solving the fluid equations in both domains. If I understand you correctly you will need to set your heatsink to a solid domain.

November 7, 2009, 07:04		#7
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,854 Rep Power: 144	You are doing a Conjugate Heat Transfer (CHT) simulation, see the heating coil tutorial for how to set them up.