The local media radiant temperature for the calculation of comfort in areas characterized by Radiant surfaces

Abstract

Thermo-hygrometric indoor conditions, as well known in literature, depend on the indices directly measurable in the place (Tba, Tbu, φa, Va) and analytical solutions (Tmr, Top) and also on subjective assessments, metabolic activity carried out, and thermal resistance of clothing. They are tied to the subject occupied position within the work environment, substantially. In air conditioned rooms designed by systems with average parameters, it may happen that an individual, in some places or times, may feel sensations of thermal discomfort. These phenomena can be exacerbated by heat exchanges occurring in the presence of sources of radiation, such as radiant floors or ceilings or large glass surfaces sunny; these surfaces accentuate the radiative heat exchange with the body surfaces of the exposed individual. This paper proposes a "local mean radiant temperature" valid for the regular calculation of comfort in environments characterized by the presence of radiating surfaces. The present study compares the values of the parameters representing the hygrothermal comfort punctual, PMV, in environments characterized by radiating surfaces located in specific positions (ceiling, floor or walls), calculated with the local radiant temperature suggested in this study, with the corresponding values obtained with the mean radiant temperature proposed by the literature.