CARRIAGE AND RAILCAR HEATING INFLUENCE OF THE RELATIVE AIR HUMIDITY ON THE DESIGNING OF THE COOLING PART OF AIR CONDITIONING PLANTS IN PASSENGER COACHES

The present report deals with the influence exerted by the cooling and dehumidifying of the outside air which is introduced by the air conditioning plant on the design of the cooling portion of the latter. This report is based on a very large mass of meteorological data which represent the climatic conditions in two cities (Bonn and Barcelona). These two cities represent, on one hand, the climate of Central Europe (and much of Western Europe also) and, on the other hand, that of the European coast of the Mediterranean. The worst combination of temperature and relative humidity of the air for each of these climates has been used as a basis of calculation excepting only those occasional extremes that occur, on average, for only about one hour per year. It appeared that as regards both climates, the maximum output for cooling and dehumidifying of the outside air would be required at an ambient temperature of about 29 degrees Centigrade. The relative humidity decreased so rapidly at higher temperature that the cooling output diminished again. The total cooling output of an air-conditioning plant intended to achieve those conditions of comfort in a railway carriage which have been set out in Interim Report ORE B 30/RP 4, part I, is a function of the influence of heat tranfer, solar radiation, emission of heat by passengers and cooling and dehumidifying of outside air introduced by an air conditioning plant. The first three causes of influence have been dealt with by Interim Report ORE B 30/RP 4, part II, and the fourth cause is the subject of the present report, which therefore represents a supplement to Interim Report RP 4. A summary of the total cooling output as a function of the ambient temperature and the rate of occupation of the vehicles, was given in Interim Report ORE B 30/RP 11, section 2.6. For this results of Interim Reports RP 4 and RP 12 were used.

• Supplemental Notes:
  • Restrictions on the use of this document are contained in the explanatory material.
• Corporate Authors:

  International Union of Railways

  Office of Research and Experiments
  Utrecht,   Netherlands 
• Publication Date: 1962-7

Media Info

• Features: Appendices;
• Pagination: 12 p.

Subject/Index Terms

• TRT Terms: Air conditioning systems; Heating, cooling and ventilation equipment; Humidity; Passenger cars
• Old TRIS Terms: Question b30
• Subject Areas: Bridges and other structures; Railroads;

Filing Info

• Accession Number: 00053056
• Record Type: Publication
• Source Agency: International Union of Railways
• Report/Paper Numbers: B30/RP 12/E Intrm Rpt.
• Files: TRIS
• Created Date: Jul 8 1994 12:00AM