Factors Affecting the Design of an Air Conditioning and Pressurizing System: The Desirable conditions from the Point of View of Comfort of Passengers Approached from the Physiological Aspect

Abstract

IN designing for passenger comfort in modern commercial aircraft, many laboratory tests and research investigations have shown that the fundamental requirement for human comfort is physiological, and can be summed up by saying that the optimum conditions for comfort are those existing when the body can maintain complete thermal equilibrium, with only minor adjustments in the heat regulating mechanism of the body. Heat is produced in the human body by the process known as metabolism, in which food is oxidized, or absorbed, by the cells in the body. The body temperature is the result of the automatic balancing of this heat production—which is more than the amount needed to keep the body warm—and the heat loss from the body. Heat is lost by radiation, convection, and evaporation. The radiation loss is dependent upon the skin, or clothing, temperature, and also the temperature of any surrounding surfaces. The convective heat loss is a function of air velocity over the body and a positive temperature differential between the skin, or clothing temperature, and that of the surrounding atmosphere. The evaporative loss is a function of temperature, velocity, and humidity, and takes place when the partial pressure of the water vapour in the surrounding air is less than the pressure of the moisture on the skin, or in the lungs.

Citation

Brice, P.E.R. (1949), "Factors Affecting the Design of an Air Conditioning and Pressurizing System: The Desirable conditions from the Point of View of Comfort of Passengers Approached from the Physiological Aspect", Aircraft Engineering and Aerospace Technology, Vol. 21 No. 3, pp. 86-91. https://doi.org/10.1108/eb031739