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Abstract The Predicted Mean Vote (PMV) and the Predicted Percentage of Dissatisfied (PPD) indices are used to assess the indoor environment in terms of human thermal comfort-discomfort. In this study, an experimental combined objective and subjective investigation of thermal comfort perception has been performed in students between 16-18 years old, in a non-air-conditioned school building in Gerakas municipality within the urban greater Athens area. The objective approach included instrumentation measurements and data processing according to ISO 7730, whereas, the subjective one was based on answers collection following ISO 10551. The study is mainly devoted to the verification of Fanger's approach in a building, in free running conditions, under a mild (moderate) climate. The comparison between instrumentation data and questionnaire results presented an underestimation of the mean vote, predicting a cooler sensation than the actual one. Finally, the knowledge of human thermal perception indoors is a first approach in order to control the energy demands/savings as well as the emissions of a building complex having impact in urban microclimate and urban air quality. [ABSTRACT FROM AUTHOR]

The main aim of this study is a comprehensive analysis of long-term monitoring data of thermal comfort and discomfort parameters in small identical test buildings equipped with different heating/cooling systems. Calculations of PPD index expressed the human perception of thermal comfort and such discomfort factors like draught rate and vertical air temperature difference are provided for the room in winter season running three different heating systems - electric heater, air-air heat pump and air-water heat pump, as well as for the summer cooling with split type air conditioning systems. It is shown that the type of heating/cooling system and its working regime has a significant impact on thermal comfort conditions in the room. Recommendations for the optimal operating regimes and choice of the heating system from the thermal comfort point of view are provided. [ABSTRACT FROM AUTHOR]

Numerical simulation method was used to study the effects of the thermal comfort by air supply temperature and air supply outlet angle under of the mode of stratum ventilation in an office and the indoor thermal environment was evaluated by using the energy utilization coefficient index. The study indicated that, the PPD value indoor increased initially and then decreased with the increasing of the air supply outlet angle, and the maximum value was obtained when the air supply outlet angle was 90 degrees. The effect of air supply outlet angle and air supply temperature on energy utilization was smaller in the working condition of stratum ventilation, and the energy utilization coefficient were greater than 1 in different working conditions, which showed a certain energy saving effect existed. [ABSTRACT FROM AUTHOR]

In this work, all existing smartphone and web applications for the calculation of the PMV index running on different platforms for mobile devices have been compared with a reference software compliant with ISO 7730 Standard. Unfortunately, only four apps take into account all the six variables responsible for the thermal sensation (air temperature, mean radiant temperature, air velocity, relative humidity, metabolic rate and clothing thermal insulation) and in some cases data input appeared very hard (e.g. impossibility to consider decimal values). In addition, only one app seemed to take into account the correction of basic clothing insulation values due to pumping effect. Based on results from this preliminary test, we can conclude that web apps and smartphone tools for the evaluation of thermal comfort conditions by means of PMV presently on the market have to be used with special care (or, better, should not be used) especially by not skilled users could use them even for professional reasons. [ABSTRACT FROM AUTHOR]

The aim of this study is detailed analysis of long-term monitoring data of thermal comfort conditions and energy efficiency in small test buildings equipped with different heating systems. Calculations of PPD index and local thermal discomfort factors are provided for the test buildings during three weeks of heating season. It is shown that the type of heating system has influence not only on heating energy need, but also on thermal comfort conditions in the room. [ABSTRACT FROM AUTHOR]