Document b5nKGojdE6Ge3e7rgZGBDwZwg

612 CHAPTER 23 'r; 1958sGuide NOTE: For conditions other thon 120 F ceiling ond 65 F AUST- :: (chonges not greater than 40.F In ceiling temp ond 20 F in AUiST), For eoch 10 F increose in ceiling temp, nqe increases 15% For each lOFdecrease in ceiling temp, nqe decreases 15% For each 10 F increase in AUST, Aqc decreases 5% i ii i i 0 F Infiltrotion Air Tempos o '"x X '''-40 F Infiltration Air Temp 0 1000 2000 3000 4000 . 5000 6000 INFILTRATION RATE, CU FT PER HR Fig. 11. Additional Heat Flow from Ceiling due to Infiltration Air* Ceiling at 120 F, all other surfaces at 65 F (24% X.12.X 8 ft high room) Natural convection from heated floor ?= = 0.32 (!,, - *.)-" Natural convection from heated wall _ (8) q, = 0:26 (lp - ,,)> (9) Fig. 10 shows panel convection outputs calculated from these equations. Infiltration and ventilation increase the convection from panels. Figs. 11 and 12 show the amount of increase Aq0 observed in the ASHAE En vironment Laboratory.6' 7 Equations 7 and 8 and .Figs. 11 and 12 were used in the development of the design data for this chapter. Note: For conditions other than 85 F floor and 65 F AUST (changes not greater than 15 F) For 5 F increose in floor temp, increose *qc 5% For 5 F decrease in floor temp, decreose Aqc 5% For 5 F increase in-AUST, increose Aqc 5% For 5 F decreose in AUST, decrease Aqc 5% 1l1 i i 2 air changes--'"'^ r\ 0 F infiltra tion air i i i 1 air change--' "i i i, i i V20 F inf air i i i i i i 1 ^40 F-inf.air i i i i_ O 1000 2000 3000 4000 5000.. 6000 INFILTRATION RATE - CU FT PER HR . Fig. 12. Additional Heat Output from Floor due to Infiltration Air (Floor 85 F, all other surfaces 65 F; 24% x 12 x 8 ft high room) Panel. Heating 613 to Overall Coefficient of Heat Transfer Combined Heat Transfer The heat transfer from-a panel to a room can be determined by adding the radiant heat transfer from Fig. 9 to the convective heat transfer from Fig. 10. - Use of Fig. 9 requires the calculation of the AUST, the area-weighted average surface temperature of the unheated surfaces in the room. In Fig. 14. OVERALL COEFFICIENT OF HEAT TRANSFER U-BTU PER $1R)(SQ FTXF DEO) Inside Wall Surface Temperature Correction for Inside Air Temperatures Other Than 70 F ,m + correction ~ *w -- correction ta = inside air temperature t# *= inside wall surface temperature based on t* = 70 F tw' = actual inside wall surface temperature