Document bmJQVQz7GomL5mNYq3xNzOG3

244 Chapter 13 1945 Guide For a radiator,-the' finish coatTof _paint'affects~the"heat70utput.--Oil - paints of any color will give about the same results as unpainted black or rusty surfaces, but an aluminum or a bronze paint will reduce the heat emitted by radiation. The net effect may be a reduction of 10 per cent or more in the total heat output of the radiator5*-7. - Radiator enclosures and convector casings affect the heat distribution within the room as well as the total amount of heat supplied by the steam or hot water. Heating Effect For several years the term heating effect has been used to designate the relation between the useful output of a radiator, in the comfort zone of a room, and the total input as measured by steam condensation or -water temperatures9- ". The application of such a heating effect factor is a recog- nrTrrmrm < old room temp in deg F YIIiTI ii 11 1 i. iI.IJL 11 i Ik k 5.60 lb convector No. 1 534 lb convector No. 22 6.12 lb convector No. 6 6.32 ib 5-tube radiator Temperature in deg F Position No. 3 Position No. 1 30* level Eouiv Dili 30* level Equiv Dill 67.7 662 15 67.4 65.9 *1.5 68.2' 64.3 3.9 68.0 . 67.9 66.6 1.4 68.0 67.9 0.0 68.2 65.1 2.9 66.4 12 Radiators and Convectt 245 the eupatheoscope-for evaluating_theenvironment produced, has been, suggested by the University of Illinois. The principle underlying the eupatheoscope involves the measurement of the heat loss from a sizable 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 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 show that while the air temperature at the. 30-in. level is the same for the three convectors and the one large-tube cast-iron 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 convectors, TTTTTTT1Tm Cold room temp in eg F T ITT ii il L 5.91 lb convector No. 1 6T7 lb convector No. 22 620 lb convector No. 6 632 lb 5*tube radiator Temperature in deg F Position No. 3 position No. 1 30" level Eouiv Dirt 30" level Equiv Drff 69.4 675 1.6 69.9 682 1.7 68.7 67.6 1.1 67.9 67.9 05 682 66.4 15 12 34 5 6 7 HEIGHT ABOVE FLOOR IN FEET Fic. 2. Temperature Gradients and Equivalent Temperatures for Radiator and Convectors with Common 30 in. Level Temperature nition that some radiators and convectors use less steam than others for producing equal comfort heating results in the room. No standard method for evaluating the-heating effect of radiators and convectors and correlating it with comfort has yet been accepted. One method, with test data11 on radiators and convectors, and making use of Heat Emission from Radiators, by K. F. Rubert (Cornell University, Engineering Experiment Station Bulletin No. 24. 1937). Comparative Tests of Radiator Finishes, by W. H. Severns (A.S.H.V.E. Transactions, Vol. 33, 1927, p. 41). *Heat Loss from Direct Radiation, by J. R. Allen (A.S.H.V.E. Transactions, Vol. 26, 1920, p. 11). Heat Output of Concealed Radiators, by E. A. Allcut (University of Toronto, School of Engineering Research. Bulletin No. 140, 1933). The Heating Effect of Radiators, by Charles Brabbee (A.S.H.V.E. Transactions, Vol. 33, 1927, p. 33). ... ,#University of Illinois, Engineering Experiment Station Bulletins Nos. 192 and 223. and Investigation of Heating Rooms with Direct Steam Radiators Equipped with Enclosures and Shields, by A. C. Willard. A. P. Kratz, M. K. Fahnestock and S. Konzo (A.S.H.V.E. Transactions. Vol. 35, 1929, p. 77). *A S H.V.E. Research Report No. 962--The Application of the Eupatheoscope for Measuring the Performance of Direct Radiators and Convectors in Terms of Equivalent Temperature, by A. C. Willard, A. P. Kratz and M. K. Fahnestock (A.S.H.V.E. Transactions, Vol. 39, 1933, p. 303). Fig. 3. 1 23 4 56 HPGHT ABOVE FLOOR IN FEET Temperature Gradients and Equivalent Temperatures for Radiator and Convectors with Common Equivalent Temperature and the same as the air temperature in the case of the radiator. The 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 are 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 & position in the test room. The difference between the minimum and the maximum amount of heat required to maintain the common equivalent temperature is of the order of 7 per cent. The Kata thermometer12, the thermo-integrator15-14, and the globe15 N1,o0. 88553d ftrroomm rUr, S. Public HealtTh ServiceaRIraeport, pp. 22y93W-2.3J3-7,MSCeLpotnenmebueran5.a 1c9.2r4.). Yaglog lou. (Reprint WinsbM. Ii?inrInt?!?tor~A New Instrument for the Observation of Thermal Interchanges, by C.-E. A. w.mow and Leonard Greenburg (A.S.H.V.E. Transactions. Vl. 41. 1935, p. 149). I-MMoitaSy/r11,' Thermo-Integrator. by C.-E. A. Winslow. A. P. Gagge. Leonard Greenburg. u_ IJ^ama and E. J. Rodee. (The American Journal ofHygiene. Vol. 22, No. 1, July, 1935, pp. 137-156). (The o/HylitnmVo'r34 No^f f HeatinB imd Ventilation.by T. Bedford and C. G. Warner.