Aerodynamic drag in cycling team time trials

[en] In a team time trial (TTT), the main strategy is based on drafting, where team members alternately take the lead while others ride behind the leading cyclist. TTTs can contain up to 9 riders of the same team. To the best of our knowledge, systematic aerodynamic studies of drafting groups from 2 up to 9 riders have not yet been published. Therefore, this paper presents such an analysis for up to 9 drafting cyclists in a single paceline, with wheel-to wheel spacings d ¼ 0.05, 0.15, 0.5, 1 and 5m. A total of 47 Computational Fluid Dynamics (CFD) simulations are performed with the 3D RANS equations, standard k-ε model and scalable wall functions and validated with wind-tunnel measurements. In groups of up to 5 identical riders with d up to 1 m, the last rider has the lowest drag but this is not the case for larger groups. A closely drafting group of 7, 8 or 9 riders has an average drag that is about half that of an isolated rider. However, for much longer theoretical single pacelines, a staggered peloton configuration can yet be about two times more drag efficient.

Disciplines :

Mechanical engineering
Aerospace & aeronautics engineering

Author, co-author :

Blocken, Bert

Toparlar, Yasin

van Druenen, Thijs

Andrianne, Thomas ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Interactions Fluide-Structure - Aérodynamique expérimentale

Language :

English

Title :

Aerodynamic drag in cycling team time trials

Publication date :

September 2018

Journal title :

Journal of Wind Engineering and Industrial Aerodynamics

ISSN :

0167-6105

eISSN :

1872-8197

Publisher :

Elsevier, Amsterdam, Netherlands

Volume :

182

Pages :

128-145

Peer reviewed :

Peer Reviewed verified by ORBi

Available on ORBi :

since 03 December 2018

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