Document mbxeqnEJEyp2pmrrX5KDNw9Nb

HEATING VENTILATING AIR CONDITIONING CUIDE 1943 suggested by the University of Illinois. The principle underlying the eupatheoscope involves the measurement of the heat loss from afsizable body by radiation and convection, when the surface is maintained at some constant temperature. Through the use of this instrument and its calibration curve, non-uniform environments may be referred to uniform A in n 11 i.i i in.Cold room temp in deg F 5-60 |b convector No. 1 5.84 lb convector No. 22 16-12 lb convector No. 6 6.32 ib 5-tube radiator TTo7- `3 4 => 6 / 8 9 JO Jtqmvalent net steam condensed, lb per hour Temperature in dee F Position No. 3 Position Na-1 30* level Equiv Ditf 30* level Equiv Riff 67.7 66.2 *1.5 67.4 66.0 67.9 65.9 *15 66.6 *1.4 67.9 00 68.2 68.0 68.2 64.3 *39 651 2 9 66.4 15 , r*r CT5 7" Convector No. 22 Convector Na 1 non-ferrous cast iron heating unit heating unit Tjrr - 5fh . 3 's-iFli--' Fig. 2. 5-tube cast iron radiator Convector Na 6 non-ferrous heating unit HEIGHT ABOVE FLOOR IN FEET Temperature Gradients and Equivalent Temperatures for'Radiator and Convectors with Common 30 in. Level Temperature . JLULLTffiUTTrmT Cold rooni temp in { 3 l T F 5.91 lb convertor No. 1 ;I IE 6.17 Ib convector Na 22 6ij2p to convertor Na 6 632 Ib tube radiator To Temperature in dec F Position Na 3 ': Position Na`l 30-level tquw Dirt 30-level Eauiv Ditf 69.4 675 *1.6 69.9 682 *1.7 68.7 67.6 *1.1 67.9 67.9 OX) 68J> 66.4 15 1 23 4 5o / HEIGHT ABOVE FLOOR IN FEET Fig..3.. Temperature Gradients and Equivalent Temperatures for Radiator' and Convectors with Common Equivalent Temperature environments in which the air and all surrounding surfaces are at the same temperature. The temperatures of the uniform environments are referred to as equivalent temperatures. Data given in Fig. 2 shows that while the air temperature at the 30 in. level is the same for the three convectors and the one large-tube cast-iron 266 CHAPTER 13. RADIATORS AND CONVECTORS radiator, in position No. 3 in the test room, the equivalent temperature is 1.5 F lower than the air temperature in the case of the three.convectdrs; and the same as. the" air temperature in the case of the radiator.* ,'Tjjie. difference between the minimum and the .maximum, amount, of heat required to maintain the common air. temperature, at the 30 in. level, is of the order of 13 per cent. In Fig. 3- aire .shown the results' of tests made with the same three convectors and the one large-tube cast-iron radiator, so adjusted in size that each gave approximately the same equivalent temperature in the No. 3 position in the test room.. The difference between the liuminum and the maximum amount-of heat required to maintain the common equivalent temperature is. of the , order-oL 7 per. cent. . . . The Kata thermometer11, the thermo-integrator12,13, and. the globe14 Fig. 4. Steam Consumption of Exposed and Concealed Radiators ' thermometer are other instruments which have been used to measure ~ the influence of air temperature, air movement' and radiation in an environment. ' The following:statements applying to;the use of radiators are based on experience and test results: '' 1. The heating effect of a radiator cannot be judged solely-by the amount of steam condensed within the radiator. . ', ' 2. Smaller floor-to-ceiling temperature differentials can be maintained with long; low,' thin, direct radiators, than is possible with high, direct radiators. 3. The larger portion of the floor-to-ceiling temperature differential in a room of average ceiling height heated with direct radiators occurs between the floor and the breathing level. "The Kata'Thermometer Its Value and Defects, by W. J. McConnell and C. P. Yagloglou. (Reprint No. 953 from U. S. Public Health Service Report, pp. 2293-2337. September 5, 1924). "The Thermo-Integrator--A New Instrument for the Observation of Thermal interchanges, by C.-E..A. Winslow and Leonard Greenburg (A.S.H.V.E. Transactions, Vol. 41, 1935, p. 149).- . - ;. "The Calibration of the Thermo-Integrator, by C.-E.-A. Winslow, A. P. Gagge, Leonard Greenburg, I. M. Moriyama and E. J. Rodee. {The American Journal ofHygiene,.Vol. 22, No. 1, July, 1935, ppi 137*156). "The Globe Thermometer in Studies of Heating and Ventilation, by T. Bedford-and C. G. Warner^' ' (The Journal of Hygiene, Vol. 34, No.' 4). 267