Document k69Gqpdyb9RBXQ2pwrbgvpv5O

936 CHAPTER 48 .. 1949 Guide quired, control response must be phenomenally fast; For'example,: on some the air going to the cabin from jet engine compressor can change temperature at rate of 150 deg per second. This,- coupled with the fact that on smaller size pursuit ships air is changed in cabin as much as four times per minute, makes instantaneous sensing of change , and-extremely rapid, control movement essential. Also, in airplanes' operating at Mach numbers in excess of 0.7, the control must .react to. large adiabatic tem perature rises encountered. Some of these problems are so new that con trols still have not been developed which will meet all of desired conditions. However, present studies being made by control manufacturers should result in developments of. such controls in the near future. BIBLIOGRAPHY ... Railway Passenger Cars Report on Performance and Cost of Operation of 1937 Internal Combustion Engine Mechanical Compression-Equipment for Air Conditioning Railroad Passenger Cars, by Division of Equipment Research, Association of American Railroads, May 1, 1937. Report on Relative Performance of Air Filters, by Mechanical Division, Associa tion o/Awierican Railroads, January 15,1938. Air Conditioning of Railroad Passenger Cars, by L. W; Wallace and G. G. Early, Jr. (A .S'.M.E. Transactions, November, 1937). Passenger Car Cooling Methods, by Kenneth Cartwright (Refrigerating Engineer ing, February, 1936, p. 83 and March, 1936, p. 158). Diesel Drive for Passenger Air Conditioning, by J. R. Hornaday (Refrigerating Engineering, March, 1912, p. 139). Railroad Air Conditioning, by Gordon T. Wilson (Refrigerating Engineering, May. 1943, p. 323). Railway Air Conditioning, by M. R. Eastin, August-December 1942, Railway Elec. Engr. Head-End Power for Railway Cars, by F. L. Sahlmann and E. M. Bill, May 1939, Railway Elec. Engr. Head-End Power for Streamlined Passenger Trains, by J. D. Loftis, October 26, 1946, A.S.M.E. Raleigh Section. Bases aha Automobiles ' Bus Heating, by E. T. Todd and F. O. Gadd (Heating and Ventilating, Dec. 1946. p. 83). Air Conditioning of Automobiles and Buses;.by L. W. Child (Society of Automotive Engineers Journal, June, 1938). Bus Air Conditioning, by Jerry Hicke (Heating, Piping and Air Conditioning, October, 1938, p. 639). ' Bus Air Conditioning, by A. J. Mallinckrodt and Lars Hanson (Refrigerating Engi neering, June,1939, p.388). Problems in Air Conditioning Automobiles,. fly F. J. Linsenmeyer (Society of Automotive Engineers Journal, July, 1939). P.C.C. Car Ventilation, B-3697 Westinghouse Electric Corp., September 1946. Airplanes Comfort in High Altitude Flying, by D. W. Tomlinson (A.S.H.V.E. Transactions, Vol.47, 1941, p. 57). Heat Exchangers for Aircraft, by Arthur J. Hess (Refrigerating Engineering, Sep tember, 1944, p. 192). ' Heating and Ventilating for Transport Airplanes, by B. M. Brod (A.S.H.V.E. .-Transactions, Vol. 52; 1946). Comfortization of Aircraft, by Albert A. Amhym, (Pitman Publishing Corp., New York, 1945). , /. . , Refrigeration for Air Conditioning Pressurized Transport Aircraft, by B. L. Mes- singer, (Healing and Ventilating, January, 1946, p. 83). ........... CHAPTER 49 MARINE HEATING, VENTILATION, AIR CONDITIONING General Considerations, Ship Construction Features, Factors Affecting Design, Ventilation Requirement for Various Types of Space, Air Conditioning Space Treatment, Typical Air Conditioning Systems, Types of Refrigerating Systems, Dehumidification, Ship Insulation THE importance of adequate shipboard heating, ventilation, and air conditioning arrangements cannot be overemphasized. Installations must be designed to keep the passengers comfortable and the operating personnel physically and mentally fit. The provision of satisfactory living and working conditions is one of the most economical means of keeping a high morale. GENERAL CONSIDERATIONS A ship must be self-sufficient and provide for all human needs. Facilities must be limited to the minimum space and weight practicable to conserve . dead weight and to increase the pay load. The pay load may be expressed in terms of cargo-carrying'ability, passenger-carrying capacity, fighting strength, or towing ability. Conditions in living spaces must permit adequate rest and comfort. Passenger accommodations must be treated to provide service and living conditions similar to those afforded by the various classes of hotels. Many of the, expedients used ashore for this purpose are not applicable afloat. For instance, all living quarters aboard ship cannot be located at a dis tance from the power plant, but must often have boundaries in common with heat producing spaces. The thermal conductivity of shipbuilding materials such as steel, copper, brass, etc., is many times the value for building materials used ashore, and this, together with concentrated . arrangement of equipment, produces a difficult heat transfer and insulation problem. Furthermore, the use of portholes, windows, skylights, and sim ilar openings is greatly restricted in marine applications because, of the necessity for strength, water-tightness and protection from the sea in foul weather. During' wartime, the utility of portholes, windows, and sky lights is greatly restricted because they must be fitted with light-excluding devices. Mechanical ventilation is absolutely necessary for most shipboard spaces to enable the crew to operate the vessel, to prevent the accumulation of objectionable combustible and toxic gases, and to preserve stores and cargo. Shipboard equipment must also be reliable inasmuch as specialized servicing facilities are not available at sea and failure during an emergency may jeopardize the vessel's safety. Adequate spare parts form an integral part of all equipment furnished. Experience has demonstrated that simple and foolproof heating, ventilating, and air conditioning arrangements are essen tial for satisfactory service. The only variation between ship and- shore applications is that emphasis is placed on different aspects of the design. 937 ' .