The Implications of Replacing Wind Tunnels with Computational Fluid Dynamics (CFD)

Duncan Phillips
RWDI, Toronto

The use of computational fluid dynamics (CFD) is becoming an increasingly popular means to model wind flows in and around buildings. The first published application of CFD to indoor building airflows was in the 1970's. Since then, CFD usage has expanded to include different components within buildings and flows outside.

Wind tunnel testing on buildings for wind loads was pioneered during the design of the World Trade Center in New York. Since then, the understanding of the planetary boundary layer, instrumentation, methodologies and analysis have been continuously refined.

There is a drive to replace wind tunnel testing with computational methods, with the rationale that CFD is quicker, less expensive and gives more control to the architects. Unfortunately, there is little information available to building owners and architects on the limitations of CFD for flows around buildings and communities. Firms that propose using CFD are unchallenged by facts on its limitations. Hence building owners, developers and architects are not aware of the risks they incur by using CFD for different studies traditionally conducted using wind tunnels.

The purpose of this presentation is to explain what needs to happen for CFD to replace wind tunnels. These three main challenges will be discussed, along with ongoing research and how they impact the results. Attendees will leave the session with a better grasp of how CFD works and questions to ask when acquiring either CFD or wind tunnel services to maximize value.

Accompanying PowerPoint Presentation