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RE: [EnergyPlus_Support] Comfort calculation (PMV)



   Abel,

1 - Are there any other input parameter in Energyplus which might
affect the results of PMV?

   There are the "human body emissivity" and the "human body radiant fraction",
but it is usual consider both as constants.

2 - Is the Mean Radiant Temperature from the output the same used
for comfort calculation in Energyplus?

   I suppose that this is right, but as Brent says, try to take a look at
"ThermalComfortMRT" report.

3 - Which value of the "Fraction radiant" is acceptable for a
person wearing light summer clothes? I used 0.6 as in the example.

   E+ uses a "Fraction radiant" equal to 0.72. Searching in their manuals, I
concluded that this parameter is constant. You can find the fraction radiant
parameter in the "EngineeringDoc.pdf", searching for "Fanger comfort Model".
This parameter is defined as "The fraction of surface effective for radiation",
and is called "feff". In my view point, this parameter only depends from the
skin area that actually emits radiation, and don't depends on the clothes.
ASHRAE recomends feff=0.7 for a seated person and feff=0.73 for a stand up
person.

4 - Which value should be used for the "Work efficiency schedule"
for house activities like walking about and housecleaning?

   I think that a work efficiency of 8% is a good value, considering a medium
mechanic work (M = 140 W/m2) and putting in the work efficiency equation: mi =
0.04368*M + 1.943 (ASHRAE).

________________________________________________________
 Engº Fábyo Luiz Pereira
 UFRGS - Laboratório de Vapor e Refrigeração
 Rua Sarmento Leite, 425 - Sala 203 - Centro - 90050-170
 Fone / Fax: +55 51 3316-3167 / 3316-3355
 www.mecanica.ufrgs.br/lafrig
 Porto Alegre - RS - BRASIL


	
	
		
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