IcePak temperature continues to drop

PeteH · August 12, 2020, 10:06

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, 11:37

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, 10:06	IcePak temperature continues to drop	#1
PeteH New Member Peter Hagan Join Date: Oct 2011 Location: Virginia, USA Posts: 12 Rep Power: 14	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!

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August 12, 2020, 11:37		#2
PeteH New Member Peter Hagan Join Date: Oct 2011 Location: Virginia, USA Posts: 12 Rep Power: 14	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.