[BLDG-SIM] Zone mean radiant temperature in eQuest

Jon Hand (clcv10) jon at esru.strath.ac.uk
Fri Oct 27 09:51:58 PDT 2006

And to further the discussion about MRT and PMV assessments....

If you do think this is important you might consider ESP-r which
allows you to calculate explicit viewfactors within the zone (for any
arbitrary shaped room, with or without surfaces acting as furniture
and the like ) as well as viewfactors between one or more 'rectangular
sensing bodies' in the zone and the surrounding surfaces.

Then you can investigate radiant asymetry as
well as the usual PMV PPD stats/graphs/frequency bins.  It will
tell you not only the surface temperatures but the temperatures within
the walls and an energy balance on the zone and at the faces of
each surface (including the long wave radiant exchange at the surfaces.

Some limitations... if you are also simulating bulk air flows there is
no agent to convert the flow rates into approximations of velocity
in the room and the clothing and metabolic rate
do not change dynamically - you supply these at results recovery
time (but then you could pose the question how many times
would PMV be over 1.5 if I adjusted the clo value to represent
taking off a jacket).  We never got around to making a sensor/thermostat
that minics PMV but you can control on resultant temperature or
some other ratio of air/MRT or even the temperature of a surface
in the room.

Really really sad folk could impose a CFD domain and then
track the plumes of heat given off by the people in the room
and see what happens when the window opens and the wind
picks up outside and look at the mean age of air as it changes
throughout the day (not recommended to do 3D adaptive transient
coupled CFD for hundreds of timesteps because your coffee gets cold
and in extreme cases friends give up on you).

-Jon Hand, ESRU, Glasgow Scotland.

You received this e-mail because you are subscribed 
to the BLDG-SIM at GARD.COM mailing list.  To unsubscribe 
from this mailing list send a blank message to 

More information about the Bldg-sim mailing list