[en] Different professional cyclists use very different hill descent positions, which indicates that prior to the present
study, there was no consensus on which position is really superior, and that most cyclists did not test different
positions, for example in wind tunnels, to find which position would give them the largest advantage. This paper
presents an aerodynamic analysis of 15 different hill descent positions. It is assumed that the hill slope is steep
enough so pedaling is not required to gain speed and that the descent does not include sharp bends necessitating
changes in position. The analysis is performed by Computational Fluid Dynamics (CFD) simulations with the 3D
RANS equations and the Transition SST k-ω model. The simulations are validated wind tunnel measurements. The
results are analyzed in terms of frontal area, drag area and surface pressure coefficient. It is shown that the
infamous “Froome” position during the Peyresourde descent of Stage 8 of the 2016 Tour de France is not aerodynamically
superior to several other positions. Other positions are up to 7.2% faster and also safer because they
provide more equal distribution of body weight over both wheels. Also several positions that allow larger power
generation are aerodynamically superior.
Andrianne, Thomas ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Interactions Fluide-Structure - Aérodynamique expérimentale
Language :
English
Title :
Aerodynamic analysis of different cyclist hill descent positions
Publication date :
October 2018
Journal title :
Journal of Wind Engineering and Industrial Aerodynamics
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