Heat transfer doesn´t happen between different domains

oliveira1820 · February 20, 2018, 00:30

Hi everybody!

I am studying a cyclotron target. The target is made of different solid parts that I set as solid domains and a liquid inside that I set as fluid domain. There is only one source of heat, the beam that i have defined as a energy source inside the fluid domain.

I can see the temperature rising inside the fluid domain, but there is no heat transfer or temperature variations in any other domain.

I have defined all the faces that correspond to an interface in the meshing to ease the interface definiton and I have defined all the interfaces with CGI connection and with a thermal contact resistance in the CFX-Pre, I have also defined all domains to Thermal Energy.

Even with all the interfaces well defined,and thermal energy and Heat Transfer activated I don´t obtain any heat transfer.

Can anybody help me?

ghorrocks · February 20, 2018, 06:24

it sounds like either you have not defined the GGI interfaces correctly, or you did not apply a heat source to generate any heat transfer.

How do you know the GGIs are well defined?

oliveira1820 · February 21, 2018, 03:42

To test the system I had defined a point source and I can see the temperature rising near the point source area, so I think the error does not happens because of the heat source.

About the GGI surfaces, what I did was define the faces as named selections on mesh, and on the CFX-Pre I constructed interfaces with the faces that touch each other on different domains. That´s all I did. Am I doing it wrong?

ghorrocks · February 21, 2018, 06:34

I have no idea what is wrong.

Can you post an image of what you are modelling and your CCL?

Opaque · February 21, 2018, 10:33

Q: Are you running a transient or steady state simulation?

If transient, what are the time scale of the process in the fluid and solid domains?

I would try steady state solution (use a large time step in the solid domains), and check the solid domains heat up at some point. If they do not, your setup has a problem somewhere; otherwise, your timescales are fairly different and you need to approach the modeling different or wait until the heat wave reaches the solids.

oliveira1820 · February 27, 2018, 01:44

I discover what was wrong!!

It was in the CFX-Post, I was treating the data and graphics the wrong way, Thanks for everything anyway guys!!!!

You´ve been helpful!!

February 20, 2018, 00:30	Heat transfer doesn´t happen between different domains	#1
oliveira1820 Senior Member Pedro Oliveira Join Date: Feb 2018 Location: Portugal Posts: 109 Rep Power: 9	Hi everybody! I am studying a cyclotron target. The target is made of different solid parts that I set as solid domains and a liquid inside that I set as fluid domain. There is only one source of heat, the beam that i have defined as a energy source inside the fluid domain. I can see the temperature rising inside the fluid domain, but there is no heat transfer or temperature variations in any other domain. I have defined all the faces that correspond to an interface in the meshing to ease the interface definiton and I have defined all the interfaces with CGI connection and with a thermal contact resistance in the CFX-Pre, I have also defined all domains to Thermal Energy. Even with all the interfaces well defined,and thermal energy and Heat Transfer activated I don´t obtain any heat transfer. Can anybody help me?

February 20, 2018, 06:24		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 18,001 Rep Power: 146	it sounds like either you have not defined the GGI interfaces correctly, or you did not apply a heat source to generate any heat transfer. How do you know the GGIs are well defined? __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

February 21, 2018, 06:34		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 18,001 Rep Power: 146	I have no idea what is wrong. Can you post an image of what you are modelling and your CCL? __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Porous domain:Interfacial area density and heat transfer coefficient	l.te	CFX	2	May 18, 2014 00:45
Heat transfer modeling between two domains	jeevan_yadav	CFX	15	August 4, 2012 07:39
How can I increase Heat Transfer at Domain Interf?	B.Simon	CFX	3	October 28, 2008 19:53
Heat Transfer between two liquids domains	Abhishek	CFX	3	December 25, 2004 04:43
Convective Heat Transfer - Heat Exchanger	Mark	CFX	6	November 15, 2004 16:55

February 21, 2018, 03:42		#3
oliveira1820 Senior Member Pedro Oliveira Join Date: Feb 2018 Location: Portugal Posts: 109 Rep Power: 9	To test the system I had defined a point source and I can see the temperature rising near the point source area, so I think the error does not happens because of the heat source. About the GGI surfaces, what I did was define the faces as named selections on mesh, and on the CFX-Pre I constructed interfaces with the faces that touch each other on different domains. That´s all I did. Am I doing it wrong?

February 21, 2018, 10:33		#5
Opaque Senior Member Join Date: Jun 2009 Posts: 1,930 Rep Power: 34	Q: Are you running a transient or steady state simulation? If transient, what are the time scale of the process in the fluid and solid domains? I would try steady state solution (use a large time step in the solid domains), and check the solid domains heat up at some point. If they do not, your setup has a problem somewhere; otherwise, your timescales are fairly different and you need to approach the modeling different or wait until the heat wave reaches the solids.

February 27, 2018, 01:44		#6
oliveira1820 Senior Member Pedro Oliveira Join Date: Feb 2018 Location: Portugal Posts: 109 Rep Power: 9	I discover what was wrong!! It was in the CFX-Post, I was treating the data and graphics the wrong way, Thanks for everything anyway guys!!!! You´ve been helpful!!