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Model Radiant Panels with DesignBuilder then with EnergyPlus

asked 2015-10-22 04:04:14 -0500

updated 2015-10-22 04:04:57 -0500


I'm looking to model a SAPP ceiling Hybrid (radiant cooling and heating ceiling panel), performing cooling and heating.

I've started modeling that on DesignBuilder by implementing a chilled ceiling.

Since the performance of DesignBuilder is limited regarding this type of system, I moved to EnergyPlus to model the heating part of this system.

In the section ZoneHVAC:LowTempratureRadiant:VariableFLow, I've tried to put Chilled Ceiling HW Water Inlet (respectively Outlet) Node in the Heating Water Inlet Node (respectively Outlet) Name section, but I couldn't find it. I also tried to replace the heating part by a radiator in DesignBuilder, but regarding the results, there are some differences with the original system.

Now I'm wondering how can I model this type of system (either on DesignBuilder or EnergyPlus).

If you have some experience on this issue, please share it.

With Many Thanks.


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answered 2015-10-22 12:15:59 -0500

Hi I model these systems all the time. here is what you have to do...

  1. assign internal source construction to your ceilings where you will have the radiant panels
  2. put all the ceilings you have in the surface group object for one zone
  3. Fill out the ZoneHVAC:LowTempratureRadiant:VariableFLow, you might not have created these nodes previously so you will need to identify the hot water and cold water nodes with your own unique names
  4. put your ZoneHVAC:LowTempratureRadiant:VariableFLow onto your equipment list for the zone
  5. make sure your equipment connections are filled out for the zone, none of your nodes in ZoneHVAC:LowTempratureRadiant:VariableFLow will be in here
  6. make two branches for your ZoneHVAC:LowTempratureRadiant:VariableFLow one for the cold side, and one for the hot side
  7. add your branches into your branchlist for the demand side of your hot water loop, and the demand side of your chilled water loop
  8. set up the boiler or district heating supply side of the loop (if you don't already have this)
  9. set up the chiller supply side of the loop (if you don't already have this)

I do this in EnergyPlus and can help if you need more with this if you need more information.

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That is working! Thank you very much Annie.

NassimJ's avatar NassimJ  ( 2015-10-23 02:22:12 -0500 )edit

answered 2016-05-24 23:24:51 -0500

James's avatar

Hi Annie,

Thank you for your detailed description on how to model LowTempratureRadiant:VariableFLow system in energyPlus. I would like to follow up on this. Actually, I am modelling ZoneHVAC:LowTempratureRadiant:Electric system for the ceiling of the house. I find difficulty in modelling this as I am not sure whether I need to create a forced air distribution system to achieve this (I am assuming the house do not have any forced HVAC systems and it just have a radiant heating system for the winter period). could you please help me to model this in energyPlus?


Regards, James

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Asked: 2015-10-22 04:04:14 -0500

Seen: 1,120 times

Last updated: Oct 22 '15