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[EnergyPlus_Support] Re: Comfort calculation (PMV)

Thank you very much Linda, Brent and Fabyo for your quick reply. 
I'm using the last version 1.2.2 030. I changed the values 
of "Fraction radiant" and "Work efficiency schedule". With 6% (0.06) 
of work efficiency corresponding with mechanic work (M=100 W/m2)the 
PMV values are even higher (average PMV=2.85)in comparison with the 
values given by WinConf software (average PMV=1.40). 
Besides, with air temperatures and MRT higher than around 32ºC, the 
increase of mechanical work results in lower PMV. That means that 
with MRT=32ºC and Ta=35ºC the PMV=4.67 when M=60 W/m2 and PMV=4.43 
when M=100 W/m2. This problem was found in both EnergyPlus and 
WinConf software. Did you hear about this "problem" before or still 
it is possible I'm entering wrong values? 
Apart from that I have been looking without success at clo values of 
a mattress and a cotton sheet to evaluate comfort during the night 
in the warm and humid conditions of Havana. If you could give me any 
source where I can find those values I will appreciate it very much.

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, Fábyo Luiz Pereira 
<fluizp@y...> wrote:
>    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 
> 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).
> ________________________________________________________
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>  UFRGS - Laboratório de Vapor e Refrigeração
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>  Fone / Fax: +55 51 3316-3167 / 3316-3355
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