3D CFD simulation of room air temperature and velocity with ceiling fan and exhaust fan and the resulting thermal comfort

Abstract

The integration of energy-efficient solutions remains an essential hurdle in the pursuit of sustainable and comfortable indoor settings. As building energy consumption continues to climb, there is an urgent need to implement methods that reduce environmental effects, and at the same time, maintain adequate thermal comfort for occupant well-being and productivity. Ceiling fans, a standard fixture in many indoor settings, have gained popularity for their ability to provide better air movement and temperature adjustment while using substantially less energy than standard HVAC systems. This work presents a 3D Computational Fluid Dynamics (CFD) investigation of thermal comfort that can be achieved with a ceiling fan and an exhaust fan. A 3D fan zone model available in ANSYS Fluent was used to model the ceiling fan, considering the ceiling fan as a solid disc. Numerical methodology has been validated by verifying the transient simulation results against the experimental data available in the literature. The work analyzes thermal comfort parameters - temperature and velocity - in a room with a typical ceiling fan or an exhaust fan available in India. The room temperature and velocity distribution are presented for different times of a day in summer for a warm and humid climatic zone in India. The results show that the thermal comfort obtained with the exhaust fan is better than that with the ceiling fan for the evening, night, and early morning.