The CPMV index for evaluating indoor thermal comfort in buildings with solar radiation

Abstract

The Predicted Mean Vote (PMV) developed by Fanger is the most widely used thermal comfort index for assessing indoor thermal environments. As the extensive use of the glass envelope in building design, the indoor thermal comfort is increasingly affected by the solar radiation. However, the original PMV has deviation in assessing the thermal comfort of solar radiation conditions, due to its neglect of solar radiation. Based on this defect, the Corrected Predicted Mean Vote (CPMV) index is proposed in this paper to evaluate the indoor thermal comfort in solar conditions. To validate the accuracy of CPMV, experimental studies have been conducted in three different types of transparent envelope buildings in Tianjin, North China. A total of 998 thermal responses from subjects were obtained in the summer and early autumn of 2017. The Thermal Sensation Vote (TSV) obtained from the subjects was used as the true value of thermal sensation. Data analysis reveals that the agreement between the PMV and TSV is poor, while the predicted values of CPMV agree quite well with the TSV. Compared with the PMV, the maximum deviation can be decreased by 79.5% with the CPMV method in evaluating the thermal comfort of solar conditions. Therefore, CPMV is validated to be applicable in evaluating the indoor thermal comfort in buildings with solar radiation.