Prediction Models of Skin Temperatures and Heat Loss by Evaporation for Thermal Comfort in Buildings in Hot and Humid Climates in Cameroon

  • Cyrille Brice Ze Ze University of Douala, Post-Graduation School for Pure and Applied Sciences, Mechanic and Energetic laboratory, BP 7141 Douala, Cameroon.
  • Léandre Nneme Nneme University of Douala, Post-Graduation School for Pure and Applied Sciences, Laboratory of Computer and Automatic Engineering, Higher Normal School of Technical Education (ENSET), BP: 1872 Douala, Cameroun.
  • Louis Monkam University of Douala, Post-Graduation School for Pure and Applied Sciences, Applied Sciences and Technologies Laboratory, University Institute of Technology (IUT), BP 8698 Douala, Cameroon.
Keywords: Skin temperature, heat loss by evaporation, hot and humid climates, skin wettedness, thermal comfort


The aim of this study is to propose models for predicting skin temperatures and heat loss by evaporation for the inclusion in the calculations of thermal comfort indicators in hot and humid areas, more particularly in sub-Saharan Africa. This will make it possible to complete the thermal comfort data for this climatic region, which for lack of it still uses the standard based on Fanger models, established mainly for the temperate zone (ISO 7730). The experiments were carried out on a representative sample of 24 people (men and women) in experimental buildings, located in the Douala-Cameroon region, representative of the hot and humid zone, as considered by numerous thermal balance references encountered in the litterature. The measurements of the ambient parameters and of the physiological parameters were carried out according to the recommended standards. 1008 skin temperature measurement points were performed on 3 levels of metabolic activity, in order to provide 72 individual average skin temperature values. Analyzes, statistical validation tests and comparisons were performed. We are able to present the most suitable prediction models, other than those of Fanger, for thermal comfort conditions in air-conditioned buildings in hot and humid areas of sub-Saharan Africa. It appears that the skin of people living in these regions has a higher thermal inertia, less water loss by diffusion or a higher skin barrier than that of people in temperate regions.


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