Document 2jO8Omqn6LDVk57d7wq2KVKgR

448 CHAPTER 24 1965 Guide And Data Boole For panels not vertical or horizontal, such as sloped glass in some types of skylights, calculation. procedures such as those shown in Tables 5 through 15 should be used. Since data are presented for only vertical, horizontal, and 45 de gree sloped surfaces and air spaoes, an orientation which most closely approximates the application condition should be used. WIND VELOCITY EFFECT ON U VALUES Table 20 shows comparative values of U for other wind velocities. When this table is used for summer U values,'it is necessary to enter the table at 7.5 mph, which c&n be inter polated between 5 and 10 mph. Any value taken from this table should be rounded to two significant figures. .< Example $: find the coefficient of transmission U of a' frame wall consisting of stucco. 25/32-in. board 2 X 4-in. studs, gypsum lath and plaster, and with 2-in.' blanket insulation between studs, for 25 mph wind velocity.; Solution: From Table 5, this wall, F37, with no. insulation between studs, has a value of (7 = 0.22. From Table 16, Part A, CoL 4, this wall, with 2-in. insulation added, has a.value of U " 0.084. Entering Table 20 in the 15 mph column, interpolate between 0.080 and 0.090 in 15 mph column proceed hori zontally to the.25 mph where the U value is found by interpolation to be 0.085. CALCULATING SURFACE TEMPERATURES In many heating and cooling load eftleutntionw it is neces sary to determine the inside surface temperature or the tem perature of the surfaces within the structure. As the resistance of any path of heat flow is expressed in Fahrenheit degrees per (Btu)/(hour) (square foot), the,resistances through any two paths of heat flow would be proportional to the tempera ture drop through these paths, and be expressed as fol lows: .-' A 1 ft ~ O ** " (fc - <.) (9) takers Si " the resistance from the indoor air to any point in the structure at which the temperature is to be deter mined. fit " the overall resistance of the wall from.indoor air to outdoor air. U indoor `air temperature. t, -- temperature to be determined. t -- outdoor air temperature. Example 10: Determine the inside surface temperature for a wall'havmg an overall coefficient of heat transmission V ** 0 25' mdoor^air temperature 70 F, and outdoor air temperature Solution: `` ; . fi - l//< - 1/1.46 = 0684 - fi* - i'/U - 1/0.25 - ^oo : Then, by Equation 9: ' 0.684 _ 70 -ti 4-00 " 70 - (- 20) ' v ;:t. --54.6 f Example 11. Determine the temperature of the bottom of fe. lasul&^ "^vto.^Wch has been glue H-uu acoustical tile. (C = 0.84).,.as -the interior ` finish! Th roof-coliM overall coefficient of r.-heat transmission 17 is 0 1 fm hoat flow up. The indoor air temperature is assumed'to b 70 F and the outdoor air temperature -- 20 F. Table .19 .... Coefficient* of Transmission (l/) for Solid Wood Doors fifv per (M [tq ft) IF Deg) Winter . TWcfcne**- Storm Door* Wood Metal No Storm Door . 1 in. Uin, If io. 2 in. 0-64 0.55 . 0-49 043 0.30 0.28 0.27 0.24 0.39 0.34 0.33 0.29 0.61 0.53 0.47 0.42 Nominal ttackneo. * Values lor wood storm doore are for approximately fi percent slam; far metal atom doon raluee apply for any percent of fi-- Table 20------Conversion Table for Wall Coefficient 0 for Various Wind Velocities ----------------- U for U for 0 to SO mph Wmd Vetodfies 0 5 . to 20 25 30 0.050 0.060 0.070 0.080 0.090 0.049 0.059 0.068 0.078 0.087 0.050 0.059 0.069 0.079 0.0S9 0.050 0.060 0.070 0.080 0.090 0.050 0.060 0.070 0.080 0.090 0.050 0.060 0.070 0.080 0.091 0.050 0.000 0.070 0.080 0.091 .0.100. 0.110 0.130 - 0.150 . 0.170 0.096 0.105 0.123 0.141 0.158- 0.099 0.108 0.127 0.147 0.166 0.100 0.109 0.129 0.149 0.169 0.100 0.110 0.131 0.151 0.171 0.101 0.111 0.131 0.151 0.172 0.101 0.111 0.131 0.152 0.172 0.190 - ,0.210 0.230 0.250 . -270 0.175 . 0.192 0.209 . 0.228 0.241 0.184 0.203 0.222 0.241 0.259 0.188 0.208 0.227 0.247 0.266 0.191 0.212 0.232 0.252 0.273 0.192 0.213 0.233 0.253 0.274 0.193 0.213 .0.234 0.254 0.275 0.290 0.310 - 0.330 0.350 . 6.370. 0.257 0.273 0.2SS 0.303 0.318 0.278 0.296 0.314 0.332 0.350 0.286 0.305 0.324 0.344 0.363 0.293 0.313 0.333 0.354 0.375 0.295 . 0.315 0.336 0.357 0.378 0.296 0.317 0.338 0.359 0.380 . 0.390 . 0.410 . 0.430 0.450 0.500 0.333. 0.347 0.362 . 0.376 0.410 0.368 0.385 0.403 0.420 0.464 0.382 0.402 0.421 0.439 0.487 0.395 0.416 0.436 0.457. 0.509 0.399 0.420 0.441 0.462. 0.514 0.401 0.422 0.444 0.465 0.518 . 0.600 0.700 0.800 . 0.900 . 1.000. 0.474 0.535 0.592 0.645 0.695 0.548 0.631 0.711. 0.789 0.865 0.581 0.675 0.766 0.858 0.949 0.612 0.716 0.821 0.927 1.034 0.620 0.728 0.836 0.946. 1.058 0.628 0.736 0.847 0.960 1.075 . 1.100 1.200 , 1.300 0.742 0.786 0.828 0.939 1.010 1.080 1.039 1.129 1.217 1.142 1.250 1.359 1.170 1.285 1.400 1.192 1.318 1.430 * U in fircl column tt from previous tables or ae Telocity. fw jj mph wind Qesign Heat Transmission Coefficients 449 Table 21 .... Thermal Conductivity (Jr) of Industrial Insulation Design Vafues (For Mean Temperalures Indicated) Exprexmd a Bt per (hoar) hqeere foot) {Fahrenheit degiw temperature diSenan pet foj Material (Competition) Ac cepted Oendtr for Ib/ai ft Uj,* f 25 Typical Conductivity k of Mean Temp F , 50 75 100 200 300 500 700 900 blankets A FELTS , ,- - . 1 .1 , .: mineral fiber Blanket-Mesh Metal' Blanket-Flexible Typo (Fine Fiber Glass Organic Bonded) 1200 370 Blanket-Flexible Type (Textile Glass Fibers. Organic Bonded) 370 i -Felt-Semi-Rigid Type (Organic Bonded) VEGETABLE A ANIMAL FIBER - Hair Felt or Hair Felt plus Jute 400 180 6-15 0.65 0.75 1.0 1:5 3.0 0.65 0.75 1.0 1.5 3.0 3-8 10 - . 0.29 0.35 0.25 0.24 0.23 0-22 0.21 0.27 0.28 0.25 0.24 0.22 0.300.28 0.27 0.25 0.23 0.32 0.30 0.28 0.26 0.24 0.43 0.41 0.36 0.33 0.30 0.28 0.27 0.26 0.24 0.22 -0.30. 0-29 0.28 0.26 0.23 0.32 0.31 0.30 0.28 0.24 0.35 0.34 0.33 0.30 0.25 0.49 0.48 0-46 0.40 0.33 0.23 0.25 0.26 0.27 0.35 0.26 0.28 0.29 0.30 0.42 0.59 0.54 0.48 0.42 0.36 0.67 0.65 0.61 0.52 0.42 0.44 0.56 BLOCKS,1 BOARDS ! ,, A pipe :: INSULATION ' ; ASBESTOS Molded Amosite A Binder Corrugated Asbestos Paper 8 ply Laminated Asbestos Paper 40 Laminations CALCIUM SILICATE CELLULAR GLASS CORKBOARD {Without Added Btnder) ' CORK (Without Added Binder, Pipe Insulation) DIATOMACEOUS SILICA 85% MAGNESIA MINERAL FIBER, High Temp (Organic Bonded, Block Insulation) HighTemp (FineFiber, Organic Bonded Insulation) High Temp (Inorganic Bonded, Block Insulation) * Blanket-Type Pipe Insolation PLASTICS Expanded polystyrene Expanded polyurethane ,, Refrigerant. 11 Expanded' Urethane (Thickness--1 in. and greater) RUBBER (Foamed, Rigid) VEGETABLE A ANIMAL FIBER Wool Felt (Pipe Insulation) Hair Felt or Hair Felt plus Jute (Pipe Insulation) 1200 15-18 300 300 300 11-13 15-17 18-20 700 27-29 1200 11-13 800 .-9 200- 5.5-8 200 7-10 1600 2000 600 21-22 23-25 11-12 400 370 6-10 31 8 1800 16-24 1200 6-15 175 1.6 210 1.5-2.5 150 4.5 180 20 180 10 -- -- -- -- 0.36 0i25 0.26 0.20 0.22 0.25 0.17 0.20 0.28 0.26 -- -- -- -- 0.38 0.26 0.27 0.21 0.23 0.27 0.16 0.21 0.30 0.28 -- .0.32 0.37 0.41 0.52 0.54 0.49 0.47 0.40 0.27 057 0.51 0.49 0.34 0.32 0.42 0.28 0.68 0:59 0.57 0.39 0.37 0.48 ,, 0.44 0.42 0.55 i 0.54 0.61 0.28 0.29 0.35 .0.38 0.42 0.65 0.70 0.22 0.24 0.28 0.23 0.25 0.35 0.29 0.29 0.43 0.34 0.36 0.40 0.50 0.29 0.35 0.42 0.56 0.28 0.30 0.17 0-18 0.21 0.22 0.23 0.31 0.33 0.29 0.30 -' 0-62 0.61 0.68 .0.72 0.75 0.80 0.63 0.78 insulating CEMENTS 85% MAGNESIA. MINERAL FIBER W ith Colloidal Clav Binder -With Hydraulic Setting Binder 600 1800' 1200 15-18 24-30 30-40 0.50 0.55 0.60 0.49 0:55 0.61 0.73 0.85 0:80 0.85 0.95 be followed. When operatioa temperatorc approaches these limits the manufacturer's iwTmfncodsPops' should i T*to for agod board stock. For diacunioa o the change in eendnetirity with age of Refrigersst' ll expanded urethane eee section trn^Factors **"* Thermal Conductivity in Chapter ,