Aerodynamic analysis of different cyclist hill descent positions

[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.

Disciplines :

Physics
Mechanical engineering
Aerospace & aeronautics engineering

Author, co-author :

Blocken, Bert

van Druenen, Thijs

Toparlar, Yasin

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

ISSN :

0167-6105

eISSN :

1872-8197

Publisher :

Elsevier, Netherlands

Volume :

181

Pages :

27-45

Peer reviewed :

Peer Reviewed verified by ORBi

Available on ORBi :

since 28 August 2018

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