IcePak temperature continues to drop

PeteH · August 12, 2020, 11:06

Hi All,
I have not posted often, but I do frequent the forum. Thanks for all the great info!
I have an issue with my icepak simulation. While the residuals seemingly converge, my temperature monitor continues to decrease with iterations, regardless of how many iterations I perform. It decreases at a linear rate.

I have an adiabatic cabinet with a rack (geometry macro) heat source placed in the center of it.

Instead of using the CRAC macro, which only allows an intake temperature, I am using a recirculating opening which allows a heat input thermal condition. In this case I am pulling -15000BTU/h from the domain. This seems to be where my issue is, because if I use a CRAC macro and set the intake temperature, the temperature plots become level.

Any help would be appreciated.

Thanks!

PeteH · August 12, 2020, 12:37

An update on my issue.
It makes more sense to me now that the temperature would continuously decrease in an adiabatic system with the given heat generation inputs.

I added wall material and an external temperature and my solution converges more quickly with a steady temperature.

August 12, 2020, 11:06	IcePak temperature continues to drop	#1
PeteH New Member Peter Hagan Join Date: Oct 2011 Location: Virginia, USA Posts: 12 Rep Power: 15	Hi All, I have not posted often, but I do frequent the forum. Thanks for all the great info! I have an issue with my icepak simulation. While the residuals seemingly converge, my temperature monitor continues to decrease with iterations, regardless of how many iterations I perform. It decreases at a linear rate. I have an adiabatic cabinet with a rack (geometry macro) heat source placed in the center of it. Instead of using the CRAC macro, which only allows an intake temperature, I am using a recirculating opening which allows a heat input thermal condition. In this case I am pulling -15000BTU/h from the domain. This seems to be where my issue is, because if I use a CRAC macro and set the intake temperature, the temperature plots become level. Any help would be appreciated. Thanks!

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Unphysical temperature drop when using dynamic mesh	peyman.havaej	OpenFOAM Running, Solving & CFD	1	June 24, 2020 09:35
High temperature methane+air	Peter	FLUENT	5	January 26, 2009 19:04
Flotherm-Icepak comparison for electronic cooling	Masoud Ameli	FLUENT	0	February 28, 2005 10:00
chemical reaction - decompostition	La S. Hyuck	CFX	1	May 23, 2001 01:07
Temperature in vessel during throttling process	Astrid	Main CFD Forum	2	January 31, 2001 03:34

August 12, 2020, 12:37		#2
PeteH New Member Peter Hagan Join Date: Oct 2011 Location: Virginia, USA Posts: 12 Rep Power: 15	An update on my issue. It makes more sense to me now that the temperature would continuously decrease in an adiabatic system with the given heat generation inputs. I added wall material and an external temperature and my solution converges more quickly with a steady temperature.