Document RJzXDzJennOqD2Qo4kkovo9EB

500 Cv-HnA^PrTitERR 24.7/ 1965 Guide And Data Book Table 7,.... Summer Design,.Sol-Air Temperatures Used for Tables 8 and 9 5of-dtrTemperature U FahmAmit fTngiaai Aoy Surface Koriz. North East South West 7 Rofio*!^1 0 - 0225 0 . <X225 ai25 0.225 0.125 0.225 am 12 Midnight 1AM 2 3 4 5 6 7- 8' 9 10 . 11 ; . 12 Noon 1 PM 2 3 4 6 6 7 8 910 11 24 Hr Avg. 77 76 76 75 74 74 74 75 77 80 .83 87 ' 90 93 94 95 94 93 91 87 85 83 81 79 ' 83.1 77 - 76 76 . 75 ' 74 74 ,76 91 106 119 129 . !3T 142 144 140 132 120 107 96 ` .90 . 85 83 " 81 .79 100.5 . 77 76 76 75 74 74 . 74 75 77 .80 ` 83 ? ;. 87 .90 . 93: 94 95 94 - 93 91 . 87 85 83 ' 81 . 79 83.1 77 76 - 76 75 " 74' 75 110 123 ' '126 125 . 117 92 93 95 95 94 93 91 . 87. 85 83 81 79 93.0 b~ *"J........irammu, rota - - 0.9, kod E vktset uj tbb column are magnitude* cf C* tbe outdoor air temperature. 77 76 76 75 74 80 93 100 103 104 100 96 92 93 94 95 94 93 91 87 85 83 81 - 79 88.4 77 76 76 75 74 74 74 75 82 93 102 110 114 115 111 104 99 95 91 88 85 83 81 . 79. 89.0 77 76 76 75 74 ; 74 74 75 78 86 93 99 104 105 104 100 96 94 91 87 85 83 81 79 86.2 77 76 76 75 74 74 74 . 75 77 80 S3 89 96 110 124 135 141 139 125 103 85 83 81 79 93.0 77 76 76 75 74 ~~~ 74 74 75 77 80 83 87 92 102 111 119 120 118 111 94 85 83 81 79 88.4 * m ^-/ -- emit cooveetiT* eooductance -- 4.0 Bta per (hr) (F dag). Examples of Use of Equivalent Temperature. Tables ' Example 5: Given: A roof is constructed of 2 in. gypsum slab on i in.- gypsum board with i:in.'insulation covered with builtup roofing, f in. tWb, and exposed to the sun. The location is the central part.of the United States! Find the rate of heat flow into the building at 2:00 p-ia. during July for an outdoor tem- perature'95 F,'and'an indoor temperature 80 F. ' . Sofution.'.From Table 8 in 2:00 p.m.! column for 2 in. gypsum plus 1 in. insulation, find the total equivalent temperature dif ferential 82 deg. The overall heat transmission, coefficient for summer is taken from Table 10 and is' found to be 0.17. The heat flow rate equals 52 X 0.17 *= 8.84 Btu per (hr) (aq ft)." Example 8: For the conditions of Example 5, find the rate ofheat flow'into`building at 2:00 p.m. during July fordeagn temperatures of 105 F (outdoor) and 78 F (indoor): Daily, range of temperature 30 deg., t.e., outdoor temperature minimum of 75 F which occurs-at 4:00 or 5:00 a.m.; this being 30 deg less than the,maximum. . -,.j , .Solution; Make correction in .equivalent temperature, differ ential in accordance with Note'5 in'Table 8 as follows:' The correction for 27-deg design temperature difference is (27 - 15) - +12: -.-u. ' 1 . The correction for 30-deg'dailjr range is ^ ^-- 5, Net total correction.is + 12 --.5 ----f-7. - : The heat-flow rate at 2:00 pjn. is (52 4- 7)X 0.17 - 10.03 Btu per (hr) (sq ft).', . - . .> J - , : . .. A. methjod>of'determiaiDg heaL-fiata rates, ,wben structure'is not given in Tables 8 or 9, is illustrated-in Example Example 7: A 4-ih. stone concrete roof covered with an average depth of 4 in. of cinder concrete (k *= 4.9), on which is plaoed a f-in. thick felt roof with $-m. pitch and slag surface, is exposed to the sun. The location is the central part of the United States. Design temperatures are: outdoor 95 F; daily range 20 deg; indoor temperature 80 F. find, the heat-flow rate at 2:00 p.m. for a day in July. - * Solution: For the purpose of selecting the equivalent tempera ture differential, this construction is assumed. to be equal approximately to an uninsulated 6-in. concrete roof, for which the equivalent .temperature is found to.be 38 deg in the 2:00 p.m. column of Table 8. Calculate the overall heat-transmission coefficient U (see Equation 3 of Chapter 24) of the roof sa follows: V. 0.375 050 _T ' + 1.33 + 1.00 + 4.0 . The heat-flow rate is then : I X 0.33 equals 12.5 Btu per (hr) (eq ft). TABLES FOR PREDICTING TOTAL HEAT TRANSFER THROUGH FENESTRATION . AREAS A fenestration is any light-transmitting opening in an ex terior building wall. It may be in the form of plate or sheet glas, insulating glass, glass block,. pattern glass or plastic panels. Any of these may be in combination with some type of interior or exterior sun control. Some have integral sun control Air-CondN'nin9 Cooling-load Table 8 .... Total Equivalent Temperature Differentials for Calculating 4 Heat Gain Through'Sunlit and Shaded Roofs Pmnfriftm of Rpo/ CoorfrvcCofl* 501 tight Coodrodioa Boofr -fnpoad to $gg l* Woodb or j* yfoodb_+ l or Jr insulation 12 38 54 62 50 26 10- 4 0 Medium Coostrudfoo 2oof* Capered to Sun V Concrete or , 4. 2* Concrete + 1' or 2* insulation or 2* Wood* 2 Gypsum or 2* Gypsum + * insulation 1' Wood1* or 7 Wood*' or + 4' rock wool 2* Concrete or in furred ceiling V Gypsum 4' Concrete or 4 Concrete with 2* insulation 6 30 48 58 50 32 14 6 2 0 20 40 52 54 42 20 10 6 0 20 .38 50 52 40 22 12 6 6* Concrete + 2* insulation Heavy Consfredion Roof*--Exposed to Sea 4 6 24 38 46 44 32 18 12 6 6 20 34 42 Koofi Covered wflh Watoi--fxpored to Sun Light construction roof with 1' water Heavy construction roof with 1' water Any roof with 6' water 0 4 16 22 18 14 10 2 0 -2 -2 -4 10 14 -2 . . .0 06 Light construction Heavy construction .toeft with Hoof Spray*--Expated to Sea 0 4 12 18 16 14' 10 2 -2 -2 2 8 12 14 12 10 0 6 Roofs m Shod* Medium construction Heavy construction -4 0 -4 -2 -2 -2 6 12 28 04 14 - . 12- 12 12 8 10 8 10- 2 0: * lariodn H in. Mi roofing with or without dag* May abo be need tor shingle toot. > Nominal thickataa of the wood.- - _ - ' Notes.for Table 8 .t toat trmxvnnaton from aattoo^) f ration and temperature diffcm---e---al _ JEquiv from above^ ^ g ;.Bwf ) diffac J (table ween outdoor and room atr. L Srerea. Calculated by Mackey and Wrigh(htmr)e(tahqofdt)(materroecftmeneetbi) and edjugted afW atudying ASHRAB original tret date. Estimated (or about August 1 in deg north latitude. (For sol-air temperatures used in calculation* sea Table 7.) For typieal dcaign day where the maximum outdoor temperature* b M F and mini- mam temperature at night i* approximately 75 F (daily range of temperature. 20 F) mean 24 hr temperature 84 F for a room temperature of 80 F. All roof* have been turned a dark color which abaorbe BO percent of aolar radiation, and reflect* only 10 percent. X Application, These value* may lie oad forall ^ air conditioning estimates; osoally without oorreetian. in latitude 0 deg to 0 deg north or south when the toed it calculated fur the boUeet weather. Note 5 explain* how to adjust tbe temperature differential for other room and outdoor temperature*. - X Ptakti Reeft. If tbe roof b peaked and tbe heat gain b primarily due to aolar radiation, ua* for the area of the roof, tbe ares projected on a horiaontal plane. 4. Attica If tbe --b decreased U percent. j| g I., b used in fm pomtlv* ventflataon, He total temperature differential for a reef expoaed to tbe eun may be 4 - ` - X Cemcrieo*. Far Uopcnjtarvfiycrvnea wtoarntfoorwcaiwarn <**#ntapwclare abacarove* u Oftreatfrom IS ieg.U tbe outdoor design tempeiatare minoa room temperatureb differentfrom tbebee* cf iSdeg.'edmct a* follow*: Whenthe diflereneeb greeter (orb**) than li deg add tbe eseeas to (or aubtraet tbe deficiency from) the above differential*. For Outdoor Dagy Range of Temperature other than 20 deg. correct Eqmvalent Temperature Difference a* fcflnwe: Outdoor Daily Range . For each 1 deg diflereaee be* thaa 20 deg - For each 1 dag difference greeter tbaa 20 deg rmwlMw Medium CouMruetias - Add idea , . . .Sabred fdeg 'S deg ` HeavyCoaslntctioa Add i dee , V >111 T 5 ..i.flabradTdeg. ( /Jsde*'-r For light ConatruetioB, apply no correction.