Document 6wrBaxbn9kkEvMgNoo7ZorG9d

60 CHAPTER 5 1959 Guide Table 7 .... Analytical Solutions for Heat Conduction in Variously Shaped Solids (Conceded) Shape of Solid Bowadory Conditions Onto Avoilobte in Graphs CHAPTER 6 Sphere immersed in fluid. Rectangular bar of infinite length. The temperature of the surrounding fluid suddenly changes from the initial uni form sphere temperature. Temperature distribution as a function of time. References: (4) p. 36; (5) pp. V-21, V-35, V-44; (10) pp. 281, 282. Heat flow as a function of time. References: (5) p. V-21; (10) p. 281. Any of the above noted boundary condi-' tions for a stab. Temperature distribution as a function of time. Combine solutions as indicated in Refs. 16 and 17. PHYSIOLOGICAL PRINCIPLES Chenuco/ Vitiation of Air, Physical Impurities in Air, Thermo/ Interchanger Between the Body and Its Environment, High Temperature Hazards, Acclimatization, Upper Limits of Heat for Men at Work, Application of Physiologic Principles to Air-Conditioning Problems, Effective Temperature Index and Comfort Zones Parallelopiped (rectangular). Any of the above noted boundary condi Temperature distribution as a function tions for a slab. of time. ENTILATION is defined in part as the process of sup remove objectionable body odors, or tobacco smoke. The con Vplying air to, or removing air from, any space by natural centration of body, odor in a room, in turn, depends upon a or mechanical means. The word in itself implies,quantity, butnumber of factors, including the dietary and hygienic habits Combine solutions as indicated in Refs. 16 and 17. air must be of the proper quality also. The term air con ditioning in its broadest sense implies control of any or all of the occupants (frequently reflecting their socio-economic status), the outdoor air supply, air space allowed per person, Cylinder of finite length. Any of the boundary conditions given above for a cylinder and a slab. Temperature distribution as a function of time. Combine solutions as indicated in Refs. 16 and 17. of the physical or chemical qualities of the air. The ASHVE Code of Minimum Requirements for Comfort Air Condition ing1 defines it "as the process by which simultaneously the temperature, moisture content, movement and quality of the air in enclosed spaces intended for human occupancy may be odor adsorbing capacity of air-conditioning processes, and temperature and relative humidity. The intensity of odor sensation has been found to vary as the logarithm of the con centration of the odoriferous substance in the air, or inversely with the logarithmic function of the amount of outdoor air Hollow cylinder of infinite exterior ra dius. The temperature of the surface suddenly changes from the initial (uniform) tem perature. Temperature distribution as a function of time. 'S! Combine solutions as'indicated in Refs. 16 and 17. maintained within required limits. If an installation cannot perform all of these functions, it shall be designated by a name that describes only the function or functions per formed." See definition of air conditioning in Chapter 1. supplied and the air space per person. The relation between air supply and occupancy has been reported by the Harvard School of Public Health*-(Table 1) and the ASHAE Research Laboratory * Outdoor air require- Heat flow at the surface as a function of time. CHEMICAL VITIATION OF AIR People living indoors bring about certain physical and Table 1 .... Minimum Outdoor Air Requirements to Remove Objectionable Body Odors Under Laboratory Conditions2 most direct use in problems in which the boundaries of the Reference: (10) p. 267. u G. M. Dusinberre: Numerical Analysis of Heat Flow (Mc chemical changes in the air about them. The oxygen content of the air Himinlghes and the carbon dioxide increases, but these changes are too slight to be significant except in air tight spaces as in submarines. Organic matter which is Type of Occupenfs Air Space per Perron Co Ft Outdoor Air Supply CFM per Perron two-dimensional shape are made up of isothermal and ad iabatic surfaces. REFERB4CES I T. K. Sherwood: Absorption and Extraction (McGraw-Hill Book Co., New York, 1937). .f Griffith and Davis: The Transmission of Heat by Radiation Graw-Hill Book Co., New York, 1949). * " Max Jakob: Elements of Heat Transfer and Insulation (John Wiley A Sons, New York, 1942). 11 H. A. Johnson: Periodic heat transfer at the inner surface of a homogeneous wall (ASHVE Transactions, Vol. 54,1948 p. 143). . 11M. P. Heisler: Temperature charts for induction and con stant temperature heating (ASMS Transactions, Vol. 69, 1947, p. 227). _; usually perceived as odors, comes from the body or clothes. Moisture and heat are given of! by the body. There is no evidence of any toxic volatile material given off by man to the ambient air. Stale air may be offensive because of odors and may induce loss of appetite and loss of energy. Ob jectionable body odors have the same effects. These reasons, whether esthetic or physiological, usually make it desirable in Heating reason with or without recirculation. Air not conditioned. Sedentary adults of average socio economic status................................. 100 200 300 500 25 16 12 7 and Convection (Department of Scientific and Industrial Re search Special Report No. 9, His Majesty's Stationery Office, London, 1933). * A. P. Colburn: A method of correlating forced convection heat transfer data and a comparison with fluid friction (Ameri can Institute of Chemical Engineers Transactions, VoJ. 29, 1933, p. 174). * W. H. McAdams: Heal Transmission (McGraw-Hill Book Co., New York). * L. M. K. Boelter, V. H. Cherry, H. A. Johnson, and R. C. 11 F. C. W. Olsen: Temperatures in solids during heating and cooling (Industrial and Engineering Chemistry, Vol. 34. 1942 P- 874). - 17 T. K. Sherwood and C. >. Reed: Applied'Mathematics in Chemical Engineering (McGraw-Hill Book Co., New York 1939). ** H. S. Carslaw: Introduction to the Mathematical Theory of the Conduction of Heat in Solids (Dover Publications, New York, 1945). 17 L. R. Ingersol), A. C.. Ingersoll, and O. J. Zobel: Heat the design of air-conditioning systems to provide for the elimination or control of odors arising from occupancy, cook ing,- or other sources. This may be accomplished by intro^ ducing odor-free air in sufficient quantities to reduce odor concentrations by dilution to a level which is not objection able. Odor-free air may be outdoor air or air which has been cleared of odors by sorption, washing, or other appropriate means. 200 Grade school children of average socio economic status....................................... 100 200 300 500 Grade school children of lower socio 23 29 21 17 11 \ l t? <| Martinelli: Heat Transfer Notes (University of California Press, Berkeley, 1946). ' V. S, Touloukian, G. A. Hawkins, and Max Jakob: Heat transfer by free convection from heated vertical surfaces Conduction (McGraw-Hill Book Co., New York, 1948, p. 209). * H. P. Gurney and J. Lurie: Charts for estimating tempera ture distribution in heating or cooling solid shapes (Industrial andEngineering Chemistry, Vol. 15, 1923, p. 1170). In the case of vitiation by a few hazardous gases such as carbon monoxide from heating, cooking, and certain in dustrial processes, no satisfactory chemical treatment for the economic status......................................... Children attending private grade 200 38 (ASMS Transactions, 1948, p. 13). 7 R. H. Heilman: Heat insulation in air conditioning (In " T. K. Sherwood: Applied Mathematics t'n Chemical En gineering (McGraw-Hill Book Co., New York, p. 241). elimination of the impurity has been found. The only satis factory solution is elimination at the source by local exhaust schools........................................................ 100 22 dustrial and Engineering Chemistry, Vol. 28, 1936, p. 782). * L. M. K. Boelter, J. T. Gier, and F. A. Ryder: Photoelec tric photometer for rapid comparison of two light sources (Illuminating Engineering Society Transactions, 1939). " A. Nessi and L. Nissolle: Mtthodes Graphigues pour L'htude des Installations de Chauffage et de Rbfrigtration en Rigime Disconltnu (Dunod, Paris, 1949). ** R. L. Perry and W. P. Berggren: Transient Heat Conduc ventilation; or, if this is impossible, reduction to a safe ' concentration by dilution. (See Chapter 7.) In the case of contamination by other matter, including volatile vapors and Heating season. Air humidified by mean of centrifugal humidifier. Wafer atomisation rate 6 to 10 gph. Total air circulation 30 cfm per penon. Sedentary adults...........................................[ 200 J 12 * Perry Moon: Scientific Basis of Illuminating Engineering tion tn Hollow Cylinders after Sudden Chance of Inner Surface gases, chemical treatment for the removal or reduction of the (McGraw-Hill Book Co., New York, 1936). * Max Jakob: Heat Transfer (John Wiley A Sons, New York, Vo!. 1, 1949). II L. E. Grinter: Numerical Methods in Engineering (The Temperature (University of California, Publications *n Engi neering 5, Vol. 59, 1944). u v. Paschkis: Method for determining unsteady-state heat transfer by means of electrical analogy (ASME Transactions. impurities has been made available through air cleaning methods, which are discussed in Chapter 24. When the only source of contamination is the human oc Summer season. At cooled and dehumidified by mean of a spray dehunddffler. Sproy water changed daily. Total air circulation 30 cfm per person. Macmillan Co., New York, 1949). Vol. 64, 1942, p. 105). cupant, and overheating is not a problem, the minimum Sedentary adults 200 <4 quantity of outdoor air needed appears to be that required to 61 T M