On the aerodynamic flow around a cyclist model at the hoods position

Abstract: Aerodynamic flow around an 1/5 scale cyclist model was studied experimentally and numerically. First, measurements of drag force were performed for the model in a low-speed wind tunnel at Reynolds numbers from 5.5 × 10 ⁴ to 1.8 × 10 ⁵. Meanwhile, numerical computation using a large eddy simulation method was performed at three Reynolds numbers of 1.1 × 10 ⁴, 6.5 × 10 ⁴ and 1.5 × 10 ⁵ to obtain the drag coefficients for comparison. Second, flow visualization was made in a water channel and the wind tunnel mentioned to examine the three-dimensional flow separation pattern on the model surface, which could also be realized from the numerical results. Finally, a wake flow survey based on the hot-wire measurements in the wind tunnel showed that in the near-wake region, the flow was featured with the formation of multiple streamwise vortices. The numerical results further indicated that these vortices were evolved from the separated flows occurred on the model surface. Graphic Abstract: [Figure not available: see fulltext.].