Document NGQankE46bv2zjGNv7yr7RyOE
318
CHAPTER 13
1958 Guide
Table 20. . Instantaneous Rates of Heat Gain Due to Transmitted Direct and Diffuse Solar Radiation bt Unshaded. Walls of 8-in Hollow Glass
Block of Types II,. Ill, IV, IVA and V Patterns
Multiply the Table 19 Values for Type l by These Percentage Factors
For Clear Atmospheres and 18 Deg Declination, North (August 1)
For SO, 40, and 50 Deg North Latitude
Note: To obtain total instantaneous heat gain add adjusted Table 19 values to the Table SI values.
Instantaneous Heat Gain Due to Transmitted Solas Radiation as a Percentage or Type I Pattern
Sun Time
Type II Pattern
Type III Pattern
AM -
i
N. NW, W, SW
NE
E
SE
S
N, NW, W, SW
NE E
SE
S
5 a.m.
6 7
8 9 10 u 12
7pJD 0 6 4 3 2 1
T PM -
100 100 100 100 100 100 100 100
N, NE, E, SE
100 100 95 95 90 90 95 90 95 85 95 95 100 95 100 100
NW W
100 100 90 100 90 too 90 100 90 90 95 95 95 100 100 100
SW s
70 70 70 70 70 70 70 70
N. NE, E, SE
70 70 65 65 65 60 65 60 65 65 70 70 70 70 70 - 70
NW W
70 70 70 70 65 70 65 70 70 65 75 65 80 75 75 90
SW 8
Sun Time
Type IV Pattern
Type IVA Pattern
AM-* i.
N, NW, W, SW
NE
E
SE
s
N. NW. W. SW
NE E
SE S
'5 a<m.
6
7 8 9 10 11 12
7 pja. 6 5 4- 3 2 1
pi-*
55 55 55 55 55 55 55 55
N, NE, E, SE
45 45 45 45 50 55 55 55
NW
35
35 35 30 25
35 45 55 .
75
80 60
40 30
30 35 50
W SW
55 55 55 55 60 50 40 45
S
55 55 55 55 55 55 55 55
N. NE, E. SE
45 35 30 55 35 35 30 55 35 40 35 55 45 45 45 55 50 65 65 50 55 85 90 60 55 70 105 95 55 55 100 115
NW W SW S
Sun Time
AM -- l
5 a.m.
-6 " 7
8
9 *-
. 10 11 12
7 p.m.. 6 5 4
3 2 1
Type V Pattern
N, NW, W SW
NE
E
SE
s
60 35 35 30 60
60 35 35 30 60 60 35 .40 35 60 60 50 65 50 60
60 80 90 90 60
60 70 105 105 90* 60 60 80 110 105* 60 60 60 85 115?
Designation of Block Type II--Semi-Light Diffusing III--Light Diffusing IV--Light Diffusing IVA--Light Diffusing V--Light Directing
pli-.
N, NE, E, SE
NW
W
SW
S
* Reduce by 30% for 30 deg N lat itude only.
block in east or west facing walls; 10 percent for south facing flat glass; 5 percent for south facing glass block walls.
Shading of Glass Areas--Shade Factors
The shade factor is defined as the total gain from a shade-glass combina tion minus the convection and radiation gain from single unshaded common window glass divided by the total incident solar radiation transmitted, by single unshaded common window glass. In equation form,
(Total Gain from \ /Convection & Radiation \
Shade Glass
) -- ( Gain from Single
I
Combination / \Unshaded Common Glass/
Shade factor =----------------------------------------- :------------------ ;--;----- ------ .
Total Solar Energy Transmitted by .
Single Unshaded Common Glass
Cooling Load
319
Table 21. Instantaneous Rates of Heat Gain by Convection and Radiation from Unshaded Walls of 8-in. Hollow Glass Block of Patterns
Type I, II, III, IV, IVA and V*
For Clear Atmospheres and 18 Deg Declination, North (August 1)
For 80 F Indoor Temperature
Note: For total instantaneous heat gain add these values to values in Table 17, or Table ' 19 adjusted by Table SO factors.
Sun Time
DryFarr.
Instantaneous Heat Gain in Btu per (hr) (sq pt) N NE E SE S SW W NW
6 7 8 9
10 11 12
1 p.m. 2
3 4 5 6 7
8 9
74 74 75 77 80
83 87 90 93 94
95 94 93 91 87
85 83
40
Degrees North Latitude
--3 --3 --3 --3 --3 --3 --3 --3
03
4* 3 --2 --2 --2 --2
1 15 17 13 --1 --1 --1 --1
0 21 26* 21 1 0 0 0
0 20 33 27 5 1 2 1
2 s 12 36 32 12 3 3 3
4 ` 6 29 32 19 5 6 5
6 8 16 26 23 9 8 7
8 10 14 14 26 25 12
9
9 10 15 11 25 37 28 11
11 11 16 11 21 44 41 17
11 11 15 11 16 45 44 30
11 10 13 10 13 43 42* 35
13 9 11 9 11 35 35 29
11 .
7
8
7
8
19 ' 21*
15
74444774 43232343
Sun Time
DryBulb
Latitude
SE
S
SW
Latitude
SE
S
SW
5 a.m. 6 .7
10 1 p.m.
7
8
74 74 75 77 80
83 87 90 93 94
95 94 93 91 87
85 83
30b Degrees North Latitude
--3 --3 --3 1 --2 --2
11 --1 --1 20 0 0 26 1 2
29 4 4
26 8 5
18 12
7
10 15 16
11 16 30
12 14 39 12 13 43
11 11 41 10 9 32 6 6 15
446 33 3
50b Degrees
North Latitude
--3 --3 --3 5 --2 --2 13 --1 --1
21 0 0 27 6 1
32 15
2
35 22
4
33 28 17
23 31 31
12 32 39
11 28 43 11 20 44
10 12 43 9 10 36 7 7 23
4 4 10 33 3
7n/ar
UI IV, IVA and V patterns and 30, 40 and 50 deg latitudes, multiply east wall values for 0.
b i?,,. xi b\iyn1.A40, andu w""est_w*aanll values floorr 5o,, 6u aoniiud 7 p..mm.. buy 11..425. r NE, E, W and NW use 40 deg North Latitude values.
Design shade factors for a number of combinations are listed in Table 25.
he total gain for a shaded window is found by multiplying the values of able 12 by the appropriate shade factor and adding to these values the corresponding values from Table 13.
The values for sunlit windows are average values based upon calculations
or several orientations. Actually the shade factor varies somwehat with nentation and time of day, because the proportion of direct to diffuse in-
ent solar radiation as well as the profile angle varies. Generally these variations may be neglected.
sokr
a number of variables affecting these ratios such as color, fit,
theref
anc^ ang^e of incidence of the solar radiation. These values,
ygp, r> must be considered as approximate, only, and will have to be
with considerable judgment. An inside shade is effective to the ex-