Flow Patterns and the Impact of Active Chilled Beam Location on Thermal Comfort in Commercial Buildings

Abstract

Chilled beams are increasingly becoming popular as a means of heating and cooling in buildings, especially in the developed nations in Europe and the US, thanks to their low operating costs and better avenues for energy savings. Considering the fact that they are installed on the ceiling and functionally vent out air at an angle to the plane of the ceiling, there is a high likelihood of a strong interaction of the jet of air with either the boundaries of the room or objects within the room. These interactions lead to interesting patterns of air movement within the building space and are also essential in normalizing the effects of the outdoor extreme climatic conditions in case of the presence of an external window. In this work, we study the effects of such interactions on the air movements in the building space and, thereby, the impact it has on comfort conditions. With the premise that such interactions are important in achieving human thermal comfort, the location of the chilled beam on the ceiling is an interesting variable to optimize and investigate. Through a series of Computational Fluid Dynamic (CFD) simulations using ANSYS Fluent and Airpak software, we investigate the dynamics of interaction between airflows and thermal comfort of humans (using Fanger’s Predictive Mean Vote, PMV, model) under the influence of an active chilled beam. These test cases from the CFD simulations are tested and validated against an experimental room set up in Andover, Massachusetts.