Re: [TRNSYS-users] Humidity capacitance ratio and internal gains

[David Bradley <bradley@tess-inc.com>]

Francois,

I would like to know more about how to set a right value for the “humidity capacitance ratio” in the .bui file.

I know that it is about taking into account the materials in the zone that absorb moisture such as furniture, clothes, etc... but I don’t know how to set a correct value for a given type of zone.

in the literature that I have seen, people typically recommend values that range from 4 to 15. I was never able to find any real justification for those values, however.

Otherwise, regarding the internal gains from the occupants, I am tempted to use a ratio of something like 0.75 for high school kids compared to “standard gain” from adults.

Has anybody had this thought already or should I just stick to the standard values?

I recall some ASHRAE research awhile ago showing that energy gains from children are actually as high if not higher than they are for adults because their metabolism is higher. I would just assume that the high school age occupants cause the same latent and sensible gains as the adults.
Kind regards,
 David

-- 
***********************************************************************
Thermal Energy System Specialists (TESS), LLC 
David BRADLEY                      22 N. Carroll Street - Suite 370 
Partner                            Madison, WI 53703 
                                   USA
P: +1.608.274.2577 
F: +1.608.278.1475
E-mail: bradley@tess-inc.com 
Web Pages:  http://www.tess-inc.com    and      http://www.trnsys.com

***********************************************************************