HVAC systems testing and check: A simplified model to predict thermal comfort conditions in moderate environments

• Published in: Applied energy 2013-04, Vol.104, p.117-127
• Main Authors: Buratti, C., Ricciardi, P., Vergoni, M.
• Format: Article
• Language: English
• Subjects: Air conditioning. Ventilation; air temperature; Applied sciences; Clothing thermal insulation influence; Correlation; Energy; Energy. Thermal use of fuels; equations; Exact sciences and technology; females; Heating, air conditioning and ventilation; insulating materials; insulation; linear models; males; Mathematical models; Moderate environments; Phases; Regression; regression analysis; Relative humidity; Simple correlations; Simplified evaluation model; Techniques, equipment. Control. Metering; temperature; Thermal comfort; Thermal insulation; Thermal-hygrometry comfort
• ISSN: 0306-2619; 1872-9118
• DOI: 10.1016/j.apenergy.2012.11.015

► New tool for testing thermal comfort in HVAC systems only measuring T and RH. ► Diagrams PMV vs. temperature for different values of relative humidity are traced. ► Diagrams are valid in moderate environments. ► Diagrams are valid in the 0.25–1.65clo range of clothing thermal insulation. ► A mean error in estimate PMV of ±0.22 was found, good for applications. An interesting tool for testing and check phases of HVAC systems was developed, in order to evaluate thermal comfort parameters only measuring temperature and relative humidity in moderate environments, for a wide range of clothing thermal insulation. A simplified approach to thermal comfort was developed in the seventies by Rohles, who found a correlation between PMV, air temperature and relative humidity, for sedentary activity and clothing thermal insulation equal to 0.6clo. An improvement of Rohles model is proposed, aiming to extend results in a wider range of clothing thermal insulation (0.25–1.65clo). Data from experimental campaigns in moderate environments were used to implement a function PMV=PMV(T, RH) and diagrams PMV vs. temperature, for different values of relative humidity, were traced (nine equations and diagrams for male, female, and both sexes, and for three ranges of Icl). Standard deviation between measured and calculated data was evaluated and a mean error on PMV of ±0.22 was found; a T-Student test was also performed and results were significant. Mean Radiant Temperature data were used to calculate Operative Temperature and to correlate to PMV and to Neutral Temperature, corresponding to thermal comfort, by means of linear regression method.