Room tempearture calculation
Room tempearture calculation
(OP)
Does anybody know how to simulate the room temperature rise, without any air conditioning system, and given room heat gain from people, lights, equipment, fenestration and initial room temperature. I need to find out at what would be the room final temperature and how long it will take to reach this temperature.





RE: Room tempearture calculation
All you need know is the specific heat and mass of everything in the room and the building, and their starting temperatures.
Chop it up into what ever time slice suits your needs.
Eventually you will reach a steady-state condition where the the heat stored term goes to zero. That temperature can be estimated by:
Tinside = (Heat in/UA)+ Toutside
Assuming of course that the outside temperature is kind enough to stay constant.
RE: Room tempearture calculation
Heat generated = heat transfered + sensible heat to objects & air in room/walls
(probably can neglect sensible heat unless there is a lot of mass in room/walls and the time aspect is critical)
-probably are standards for heat generation by people at rest
-lights, use energy output/wattage
-fenestrations (do you mean windows) - just include them with walls etc. in the heat transfer calcs.
-if you weren't looking at time, then would solve for inside temperature at which heat transfer rate = heat input. But to determine time, will need to do a time step analysis.
RE: Room tempearture calculation
The lights and appliances and equipment is easy because they all have ratings and their heat goes directly into the room. Heat transfer through walls and windows, well you are getting into an area that is involved and has lots of variables.
rmw
RE: Room tempearture calculation
RE: Room tempearture calculation
TTFN
RE: Room tempearture calculation
rmw
RE: Room tempearture calculation
The examples show "studying" at 1.7xBMR for a 1.75 lb person, making 2xBMR a reasonable design point.
TTFN
RE: Room tempearture calculation
Wow, that's a small person! :>)
RE: Room tempearture calculation
TTFN
RE: Room tempearture calculation
rmw
RE: Room tempearture calculation
ht
Didn't see anyting quite as high as 600, though. The site also gives some good basic design info. Was the 1.75 lb man bowling?
RE: Room tempearture calculation
TTFN
RE: Room tempearture calculation
Take the "V" out of HVAC and you are left with a HAC(k) job.
RE: Room tempearture calculation
My scenario was a partition wall in front of a glass curtain wall which sealed it off. We got concerned that excessive heat build up btw the window and the wall was going to pop the windows down onto the street! We ended up putting a damper into the wall.
RE: Room tempearture calculation
Regards