Thermal Comfort and Energy: CFD, BES and Field Study in a British Open Plan Office with Displacement Ventilation

Abstract

Energy efficiency and thermal comfort are necessary in designing the workplace. Accurate computational modelling and analysis methods are useful to improve the design, energy consumption and user’s comfort. This study compared the results of combined Computational Fluid Dynamics (CFD) and Building Energy Simulation (BES) with the contextual data collected through a Filed Study of Thermal Comfort (FSTC) regarding user comfort and energy in a workplace. The building was a six storey open plan office in Aberdeen, built in 2011, with displacement ventilation, “very good” BREEAM and “B” energy ratings. Each floor had 175 workstations, 1680m2 office area and approximately 3.5m2 per workstation. Thermal comfort surveys and environmental measurements were applied. The results were compared with the CFD modelling of the ventilation and thermal performance, PMV and BES energy predictions. The simulation results were in good agreement to that of the field data, indicating over 70% slightly cool and 25% neutral. The combination of CFD and BES improved the accuracy of the simulation and provided important information on optimising energy and the thermal environment. This combined simulation is useful and recommended in the design phase to achieve the balance of energy and comfort in the workplace.