Numerical investigation of flow past bluff bodies at transitional Reynolds numbers: from cylinders to cyclists

In elite cycling, small aerodynamic gains achieved through modifications to the skinsuit on a cyclist's limbs can provide a significant competitive advantage, as winning margins may be only milli-seconds in a multi-minute race. Often, a cylinder model has been used to represent the flow past an athlete's limbs. This thesis pays attention to capturing the fundamental flow characteristics of an isolated cylinder through computer modelling, especially the details of airflow near the surface as the speed changes, with validation through experiments. That study fed into improving numerical simulations on the cyclist/bicycle combination to predict the aerodynamic drag attributed to separate body parts as the legs move through a pedalling cycle. Finally, modelling of the effect of surface treatments to the limbs provides key insights on changes to the drag contributions of sub-body parts.