Predictive Capacity Analysis for Outdoor Thermal Comfort Assessments: A Case Study of Jijel City, Algeria

Abstract

Ensuring acceptable thermal comfort conditions in public spaces is nowadays a major concern of urban design. A number of indices have been proposed in the literature, namely PMV, PET, SET*, UTCI, PT, mPET and MOCI. The present study aims to find the most suitable index the outdoor thermal comfort assessment in the city of Jijel by comparing the predictive capacities of these indices in terms of frequency occurrence and by relating them with the contextual responses of users. These indices are defined, their feature is analysed and finally explored. Thermal comfort based on these indices was evaluated using RayMan and Townscope softwares. The choice among these indices needs their comparison with data gathered from a survey by questionnaire. The findings indicate a slight agreement between these indices and the perceived sensation (PESV) values in the range of -1 and +1, especially with the indices SET* and mPET. However, for the classes +2 and +4, a significant disagreement is observed. For the class +3, however, only PET, PMV and SET* are more joined to the perceived sensation values. The disagreements may be related to the physical environment characteristics, the subjective perception, and the adaptation attitude of the users. Thus, further indices calibration investigation is needed for better prediction of comfort taking into account local specificities. Based on the indices which are relatively in agreement with PESV, a neutral air temperature of 19.8 °C in winter and 20.4 °C in summer for the city of Jijel is deduced. Also, a comfort zone of 17.3 to 22.4 °C in winter and 18 to 22.8 °C in summer is extrapolated.