Thesis Defence: Stephanie Fleming

There is a reciprocal relationship between wind and buildings, as they each affect the other. Building form affects wind by altering its speed and flow patterns, and can be used to create desirable wind conditions around the building. Wind, in turn, exerts load on the building, which can be reduced with aerodynamic forms and resisted with structural systems. This establishes a relationship between wind conditions, the building form that creates these wind conditions, and the structure that stabilizes the form against these wind conditions.
 

This relationship is investigated through the development of a design methodology that allows architects to consider, in the early design stages, how wind and buildings affect each other. The thesis does not serve to propose a building; rather, it will use a building as a means for developing this method. The method consists of a pairing of computational fluid dynamics (CFD) software and finite element analysis (FEA) software. While this pairing has not been widely explored within the context of architectural design, the combined use of these software programs allows architects to integrate wind engineering considerations into their current architectural practices, without having to acquire extensive engineering knowledge. Software also provides architects with a means of quickly testing multiple design iterations in relation to these engineering considerations, because the software can perform engineering calculations or simulations much faster than if the architect were to learn and perform these calculations themselves.
 

For each building design iteration, CFD software is used to simulate the speeds and patterns of wind flow around the initial building form design. This tests the appropriateness of the wind conditions for the exterior programs that must be accommodated around the building. The speed with which these results are provided allows the architect to refine and re-test many iterations of their design until the building form creates the desired wind conditions. The CFD software is then used to evaluate the aerodynamics of the building form by providing information about the wind pressure that is exerted on each building face. The architect can change the building form to reduce the wind pressure acting on it, and then re-test the form with the CFD software to ensure that improved aerodynamics have been achieved without compromising the surrounding wind conditions. Then, the wind pressure information that is provided by the CFD software is input into the FEA software to predict how the building will react to combined wind and gravity loading. This information informs the schematic design of the building’s structural system, which is developed through another iterative process using the FEA software. 
 

The production of accurate wind and structural data is not the goal of this thesis, since accurate results are not currently available due to software limitations. Instead, this thesis seeks to develop a design method that will increase in accuracy as CFD and FEA software programs continue to be improved. In the future, CFD and FEA software programmers could potentially draw from this method to create programs that can be used together, to allow architects to consider wind as a generator of architectural form within a streamlined, software-based workflow.