Adaptive analysis of thermal comfort in university classrooms: correlation between experimental data and mathematical models

Numerous studies are in progress to support adaptive models and to establish quantitative indexes to allow the subject to optimize his comfort conditions. With the aim of finding possible correlations between experimental data and experimental surveys for moderate environments, such as university classrooms, a multiple response questionnaire was elaborated, comprehensive of information for the static and adaptive model proposed by UNI-EN-ISO 10551. The questionnaire was applied in autumn, winter and spring in classrooms of the University of Perugia, Pavia and Terni. During the campaign, all data needed to calculate both Fanger and Wray comfort indices were acquired by instrumental surveys and questionnaire compilation. By means of results analysis the following couple of parameters were correlated: Predicted Mean Vote (PMV) versus the difference between the Equivalent Uniform Temperature and the Comfort Uniform Temperature (Teu - Tu) and the Predicted Percentage of Dissatisfied (PPD) versus the absolute value of the same difference between temperatures (|Teu - Tu|). For the first couple of parameters a linear correlation was found while for the second one a second degree polynomial relation was obtained. Finally values of Operative Temperature T0 and Equivalent Uniform Temperature Teu, obtained for each single experimental survey were compared, observing a very good agreement between the two quantities, with differences that exceed 0.1 K only for a few number of values.