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<DIV><STRONG><FONT size=2 face="Courier New">Alan Abrams <</FONT></STRONG><A
href="mailto:alan@abramsdesignbuild.com"><STRONG><FONT size=2
face="Courier New">alan@abramsdesignbuild.com</FONT></STRONG></A><STRONG><FONT
size=2 face="Courier New">> asks:<BR></FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">>... is comfort a (partial)
function of radiant heat loss to<BR>> <BR>> 1. surfaces of lower
temperature--in this case the cardboard, newspaper,<BR>> bubble wrap or
shade--vs a single pane of glass at near ambient temp.<BR></FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">Yes.</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face="Courier New">> 2. a
radiant-transparent/transluscent membrane, with cold surfaces/cold<BR>> space
beyond</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face="Courier New">Yes, if the surface is transparent
to IR, eg polyethylene film.</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">No, if the surface is opaque to IR,
eg glass. You can try</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">holding each between you and a
stove burner.</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"> <BR>> In other words, is
comfort completely attributable to measurable thermal<BR>> conductance, or is
some quotient that is not attributable to assembly<BR>>
R-values?<BR></FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">ASHRAE says comfort
</FONT></STRONG><A
href="http://en.wikipedia.org/wiki/Thermal_comfort"><STRONG><FONT size=2
face="Courier New">http://en.wikipedia.org/wiki/Thermal_comfort</FONT></STRONG></A><STRONG><FONT
size=2 face="Courier New"> is</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">a function of air temp and RH, mean
radiant temp (which includes window</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">glass temps), air velocity, amount
of clothing, and human activity level.</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face="Courier New">If it's 70 F indoors and 30
outdoors, an unshuttered R2 window will have</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">a 56 F indoor glass temp. An R2
shutter over the window will have</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">a 63 F indoor shutter temp. In the
first case, a person in the center </FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">of a cubical room with 8% of the
floorspace as windows will see</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">a 0.9866x70+0.0133x56 = 69.81
mean radiant temp. With shutters,</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">the person will see a 69.91 mean
radiant temp :-)</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face="Courier New">Cranking this into the BASIC
program in the ASHRAE 55-2004</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">comfort
standard...</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face="Courier New">20 CLO = 1'clothing
insul</FONT></STRONG><STRONG><FONT size=2 face="Courier New">ation (clo)<BR>30
MET=1.1'metabolic rate (met)<BR>40 WME=0'external work (met)<BR>50 VEL=.1'air
velocity<BR>60 RH=50'relative humidity (%)<BR>70 DATA 70.043,56,70,63<BR>80 FOR
CASE=0 TO 1<BR>90 READ TAF,TWF'air and glass/shutter temps (F)<BR>100
TA=(TAF-32)/1.8'air temp (C)<BR>110 TW=(TWF-32)/1.8'glass/shutter temp
(C)<BR>120 TR=.9866*TA+.0133*TW'mean radiant temp (C)<BR>130 PA=0'water vapor
pressure<BR>140 DEF FNPS(T)=EXP(16.6536-4030.183/(TA+235))'sat vapor pressure,
kPa<BR>150 IF PA=0 THEN PA=RH*10*FNPS(TA)'water vapor pressure, Pa<BR>160
ICL=.155*CLO'clothing resistance (m^2K/W)<BR>170 M=MET*58.15'metabolic rate
(W/m^2)<BR>180 W=WME*58.15'external work in (W/m^2)<BR>190 MW=M-W'internal heat
production<BR>200 IF ICL<.078 THEN FCL=1+1.29*ICL ELSE
FCL=1.05+.645*ICL'clothing factor<BR>210 HCF=12.1*SQR(VEL)'forced convection
conductance<BR>220 TAA=TA+273'air temp (K)<BR>230 TRA=TR+273'mean radiant temp
(K)<BR>240 TCLA=TAA+(35.5-TA)/(3.5*(6.45*ICL+.1))'est clothing temp<BR>250
P1=ICL*FCL:P2=P1*3.96:P3=P1*100:P4=P1*TAA'intermediate values<BR>260
P5=308.7-.028*MW+P2*(TRA/100)^4<BR>270 XN=TCLA/100<BR>280 XF=XN<BR>290
N=0'number of iterations<BR>300 EPS=.00015'stop iteration when met<BR>310
XF=(XF+XN)/2'natural convection conductance<BR>320
HCN=2.38*ABS(100*XF-TAA)^.25<BR>330 IF HCF>HCN THEN HC=HCF ELSE HC=HCN<BR>340
XN=(P5+P4*HC-P2*XF^4)/(100+P3*HC)<BR>350 N=N+1<BR>360 IF N>150 GOTO
490<BR>370 IF ABS(XN-XF)>EPS GOTO 310<BR>380 TCL=100*XN-273'clothing surface
temp (C)<BR>390 HL1=.00305*(5733-6.99*MW-PA)'heat loss diff through skin<BR>400
IF MW>58.15 THEN HL2=.42*(MW-58.15) ELSE HL2=0'heat loss by sweating<BR>410
HL3=.000017*M*(5867-PA)'latent respiration heat loss<BR>420
HL4=.0014*M*(34-TA)'dry respiration heat loss<BR>430
HL5=3.96*FCL*(XN^4-(TRA/100)^4)'heat loss by radiation<BR>440
HL6=FCL*HC*(TCL-TA)'heat loss by convection<BR>450
TS=.303*EXP(-.036*M)+.028'thermal sensation transfer coefficient<BR>460
PMV=TS*(MW-HL1-HL2-HL3-HL4-HL5-HL6)'predicted mean vote<BR>470
PPD=100-95*EXP(-.03353*PMV^4-.2179*PMV^2)'predicted % dissatisfied<BR>480 GOTO
500<BR>490 PMV=99999!:PPD=100<BR>500 PRINT 600+CASE"'";TWF,TAF,PMV<BR>510 NEXT
CASE<BR>515 LIST 70</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">520 'Innova AirTech Instruments has
an excellent comfort web site...<BR>530
'http://www.impind.de.unifi.it/Impind/didattica/materiale/<BR>540
'microclima/innova/thermal.htm<BR></FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">56
70.043
-.3230851<BR>63
70
-.3230717 </FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face="Courier New">... it looks like we only have to
raise the unshuttered room air temp</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">from </FONT></STRONG><STRONG><FONT
size=2 face="Courier New">70 to 70.043 F to make the rooms equally comfortable,
unless you</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">are sitting right next to a
window.</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face="Courier New">Passiv Haus fascists seem to
overemphasize the effect of mean radiant</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New">temps on
comfort</FONT></STRONG><STRONG><FONT size=2
face="Courier New">.</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face="Courier New"></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2
face="Courier New">Nick</FONT></STRONG></DIV></BODY></HTML>