Investigation of energy consumption and local thermal comfort through the transient thermophysiological model and human-body exergy model for air-carrying energy system

An air-carrying energy system (ACES) is a novel terminal for air conditioning with energy-saving potential. However, there is a challenge for optimizing the system by reducing energy consumption while improving thermal comfort. Thus, this study coupling simulated non-uniform thermal environment and human body by a transient three-dimensional model integrating with the thermophysiological model. Based on the experimental and simulated results, the local thermal comfort over time was evaluated by energy and exergy analysis to explore the convenient predicted formula of exergy consumption, and then the energy consumptions of different heating/cooling radiant diffuse terminals were compared under the same thermal comfort. The results showed that the simulated temperature of indoor air and human thermal plume were consistent with the experiments (Average error is less than 5 %). Local human-body exergy analysis was correlated with PMV by being divided into the torso and other body parts. The convenient predicted formula of exergy consumption for multiple body parts was accurate with the goodness of fit R² > 0.98. The ceiling cooling was 36 % more energy efficient than the sidewall cooling. Optimized system of the ceiling heating reduced by 14 % energy consumption. This paper provides a valuable reference for optimizing systems based on comfort and energy saving.