Analysis of equivalent metabolic rate (EMT) used for predicted mean vote: A case study in Chongqing, China

Abstract

The predicted mean vote (PMV) model is widely used in air-conditioning operation management. In practice, the metabolic rate (MT), obtained by using the standard table, is the most important but inaccurate input of PMV. Existing MT measurements are inconvenient or technically inaccurate in practice. Therefore, revising the MT standard table is an effective way to improve the prediction accuracy of the PMV model. The equivalent metabolic rate (EMT) is defined as the gap between the MT and the metabolic rate inversely determined based on the PMV and thermal sensation vote (TSV). However, the distribution of the EMT in different seasons is not very clear. To quantify this regularity, a long-term survey was conducted in residential buildings in Chongqing from July 2019 to February 2020. The results show that the EMT is linearly related to the indoor air temperature (Ta). In winter and summer, there is a negative correlation. In autumn, when the indoor air temperature is lower than 22 °C, the slope is almost zero; When the temperature is higher (22–29 °C), the slope is also negative. This study provides fundamental knowledge to revise the standard table of metabolic rate.

Keywords

• Adaptive thermal comfort
• Revised metabolic rate standard table
• PMV model
• Hot summer and cold winter climate zone