Document pp7LO7yVdp2g1LJxB57xryQrw
| lii
i
296 CHAPTER 13
Table 15. Application Factors to Apply to Tables 13, 14 and 16 t'oUBTifP* Instantaneous Rates of Heat Gain fob Various Types of Single Flat Glass and Combinations of Two Sheets of Flat Glass Spaced at J in.
Glass*
Single Common Window Single Regular Plate
Single Heat Absorbing Plate Double Common Window
Double Regular Plate
Heat Absorbing Plate Outdoors\
Regular Plate Indoors
/
Normal Incidence TRANSMITTANCE
0.87 0.77 0.41 0.78
0.60 0.35
Factor to ' Aptly to Table 13
1.00 0.87. 0.48b 0.85
0.66b 0.37b
Factob to Apply to Table 14
' .
1.0(Ar)' + 0.0(F)J3, 1.0(X) + 0.26(F)1; 1.0GT) + 1.00(F) K 0.0(X) +0.10(F)i
0.6(A) + 0.55(F)?' 0.6(A) + 0.75(F) V.,
* Common window glass t in. thick. Plate glass } in. thick.
b For better precision, increase factors 10 percent when glass is in the shade.
e X values are Table 14 values.
d y values are Tablo 16 values.
Table 16. Heat Absorbed in Glass. Values of Y to be Used with Factors in Table 15 and Table 17 in the Determination of Instantaneous Rates of t Heat Gain Due to Convection and Radiation fob Various Types of Single Glass and Combinations of Two Sheets of Glass Spaced at i in.
For Clear Atmospheres and 18 Deg Declination, North (August 1)
Son Time
5 a.m. 6 7 8 9
10 11 12
1 p.m. 2-
3 4 5 6 7
40
Deobees Nokth
Latitude
SunTime
5 a.m. 6 7 8 9
10 11 12 1 p.m.
3 4 5 6 7
Latitude
30b Degrees
North Latitude
N NE
00 4 16 2 24 2 22 2 16
35 33 33 33 33
33 33 22 41 00
SE
0 7 18 22 24
22 16 6 3 3
3 3 2 1 0
S
0 1 2 2 3
5 7 9 9 6
5 3 2 1 0
Values op Y in Btupeb(hr) (sqpt)*
E SE
S SW
l 000 18 9 1 1 30 20 2 2 33 25 2 2 30 29 8 3
25 27 14
3
12 21 18
3
3 15 19 12
3 3 19 22
3 3 16 27
3 3 10 30
3 3 4 29 2 2 2 23 1 1 1 14 0002
sw SunTime
Latitude
0 5 a.m. 16 27 28 39
3 10 3 11 4 12 14 1 p.m. 21 2
27 3 26 4 21 5 U6
07
50b
Degrees North
Latitude
W NW Horn
0 1 2 2 3-
3 3 3 10 24
31 36 34 24
3
0 1 2 2 3
3 3 3 3 4
15 23 27 21
3
0 3 11 21 32
37 42 45 44 41
35 26 17 ' 6
1'
SE S SW
2 0 0' 13 1 22 2 %'
28 3 30 13
31 20 3 '
27 25
5-;
20 27 17*
9 25 25`
3 22 32
3 2
16 7
33
3l
22
11
00
* Values of Y for 8 and 9 p.m. are aero. b For N, NE, E, W, NW and horizontal use 40 deg North Latitude values.
Cooling Load
297
Table 17. Application Factors to Apply to Tables 14; and 16 to Obtain In stantaneous Rates of Heat Gain for Vertical Single Sheets of Rolled Figured Glass Having Normal Incidence Transmittances and Listed Thicknesses
(Smooth Side Indoors, Figured Side Outdoors)
(See Table 18 for Factors to Apply to Table IS Values)
Glass Pattern
NormXl
' Incidence Transmittance
Thickness, Inches
Factor to Apply to Table 14
Hammered Hammered, etched both sides
Deep ribs on 1 in. centers Hammered beat-absorbing Hammered heat absorbing, etched both sides
0.75 0.67
0.77 approx. 0.21 0.14
H. y*
1.0(X)* + 0~50(F)b.'
1.0(X) -f0.65(F)d 1.0(A) + 0.50(F)* 1.0(X) + 1.15(F)1
1.0(A) . +1.40(F)
X values are Table 14 values 1 F values are Table 16 values
c Use 0.40( F) for east and west glass
d Use 0.60(F) for east and west glass Use 0.3S( F) for east and west glass
1 Use 0.95( F) for south glass
Table 18. Instantaneous Rates of Heat Gain Due.to Transmitted Direct and Diffuse Solar Radiation by Unshaded Rolled Figured Glass
Multiply the Table IS Values by These Percentage Factors For Clear Atmospheres and 18 Degrees Declination, North (August 1) For
SO, 40, and SO Degrees North Latitude
Note: To obtain total instantaneous heat gain add adjusted Table IS values to adjusted Table 14 values
Instantaneous Heat Gain Due to Transmitted Solas Radiation as a Pehcsntaoe of Single Sheet of Common Window Glass
Sun Time
Hammered
Hammered and Etched
AM .
N, NW w, SW
NE
E
SE
s
Ni NW W. SW
NE
E ' SE S '
5 a.m. 6 " 8 9
U
7 p.m. 6 5 4 3
l
.-----------Sun Time
so 80 85 70 80
so S5 85 75 80
. 80 80
80 85 80 80 75 85 80 75
80 60 80 SO 60
80 65 75 75 ' 65
80 80 60 70 65*
80 80 SO 60 65*
Ribs on In. Centers
60 .
60 60 60
60 60
60 60
65 - 75 65 75 60 . 70 55 65 50 55 55 50
60 50 60 . . 60
55 60 50 60 55 60 55 60 55 . 50 55 50
50 50 50 . 50
Hammered Heat Absorbing
5 a.m. 6 8l 9
11 12
7 p.m. 6 54
3
1
60 ' 75 85 25 60
25 20 25 20 25
60 80 85 30 60
25 20 25 20 25
60 65 85 40 60
25 20 25 20 25
60 40 80 50 55
25 20 20 20 25
60 30 70 55 35
25 20 20 20 20
60 40 40 55 35k 25 20 20 20 20
60 60 35 40 35b 25 25 20 20 20
60 60 60 35 45b 25 25 25 20 20
------------- ---
t PM-
AM i
5 a m7
1 P-m. *
4
T PM->
N, NE E, SE
NW W
sw
S
N, NE E, SE
NW W SW
S
Hammered and Etched Heat Absorbing
N, NW w, SW
NE E SE
S
20 15 15 10 20 20 15 15 10 20 20 10 15 10 20 20 10 15 10 20 20 10 10 10 10 20 15 10 10 10 20 20 10 10 10 20 .20 20 .10 10
N, NE NW W sw E, SE
s
* Decrease values 10 percent for 30 deg latitude; increase 15 percent for 50 deg latitude
Increase values 30 percent for 50 deg latitude
:|