Early phase evaluation of building wind interaction for structural design

Abstract

Wind is a major horizontal force on structures. Due to its complex and highly variable behaviour, reliance on design codes such as Eurocode 1991-1-4 is necessary for predicting wind effects. However, such codes cannot fully account for all, infinitely variable types of structures and their resulting aerodynamic responses. The dominant alternative, wind-tunnel testing, provides detailed results but remains costly and time-consuming. In parallel, Computational Fluid Dynamics (CFD) has gained increasing credibility as a complementary approach for wind analysis. This thesis explores the application of IBOFlow, an in-house CFD flow-solver developed by Fraunhofer-Chalmers Centre, in an structural design context. Through a validation study, IBOFlow was shown to achieve favorable prediction performance and overall agreement with benchmark wind-tunnel data. Subsequently, a series of Case Studies further explored its integration into early-stage design workflows, illustrating its ability to complement code-based approaches and support early-stage design exploration. The results indicate that the integrated IBOFlow method can provide valuable predictions, while reducing the time needed for setup and calculation. The study concludes that an immersed-boundary CFD approach, when validated and integrated with design tools, can potentially offer a practical and accessible means to enhance early-phase wind assessment of complex structures for structural engineers. Keywords: