On the evolution of flow structures around a track cyclist

In this study, flow structures and their evolution over a track cyclist were investigated through wind tunnel tests. In supplement to the experiment, high-fidelity numerical simulations were also conducted to demonstrate the origins of global flow structures. In wind tunnel tests, a full-scale track cyclist mannequin was built based on the three-dimensional scanning of an elite track cyclist in a riding position of a sprint event, and a Cobra probe was used to measure the wake structures. The results show that the preeminent flow structures around the track cyclist mannequin are the streamwise vortices originating from different body parts. The evolution of these vortices involves strong vortex interactions and performs differently on each side, resulting in a dominant streamwise vortex merged behind the right thigh, which is associated with aerodynamic drag productions. In particular, leg position affects the lateral displacement between the elbow vortex and upper thigh, which is the reason for the distinct flow behaviors on each side. This study helps to better understand the flow around a track cyclist, facilitating the development of drag-saving strategies in the future.