[en] An athlete's riding posture is a key element for aerodynamic drag in cycling. Tandem cycling has the complication of having two athletes in close proximity to each other on a single tandem bicycle. The complex flow-field between the pilot and stoker in tandem cycling presents new challenges for aerodynamic optimisation. Aerodynamic drag acting on two tandem road race setups and two track time-trial setups were analysed with computational fluid dynamics (CFD) simulations. For validation purposes, wind tunnel measurements were designed providing
drag measurements from both tandem athletes simultaneously using a quarter-scale model. A max drag force deviation of 4.9% was found between the wind tunnel experiments and CFD simulations of the quarter-scale geometry. Full-scale CFD simulations of upright, crouched, time-trial and frame-clench tandem setups were
performed. The drag force experienced by individual athletes in all investigated tandem setups was compared to that of solo riders to enhance understanding of the aerodynamic interaction between both tandem athletes. The most aerodynamic tandem setup was found to be the frame-clench setup which is unique to tandem cycling and had a CDA of 0.286m2, and could provide an advantage of 8.1 s over a standard time-trial setup for a 10 km timetrial
event.
Andrianne, Thomas ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Interactions Fluide-Structure - Aérodynamique expérimentale
Hajdukiewicz, Magdalena
Language :
English
Title :
Aerodynamic drag in competitive tandem para-cycling: Road race versus time-trial positions
Publication date :
May 2018
Journal title :
Journal of Wind Engineering and Industrial Aerodynamics
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