Aerodynamic drag in cycling pelotons: New insights by CFD simulation and wind tunnel testing

Citation data:

Journal of Wind Engineering and Industrial Aerodynamics, ISSN: 0167-6105, Vol: 179, Page: 319-337

Publication Year:
2018
Captures 41
Readers 41
Mentions 8
News Mentions 6
References 1
Blog Mentions 1
Social Media 421
Tweets 289
Shares, Likes & Comments 132
Citations 3
Citation Indexes 3
DOI:
10.1016/j.jweia.2018.06.011
Author(s):
Bert Blocken; Thijs van Druenen; Yasin Toparlar; Fabio Malizia; Paul Mannion; Thomas Andrianne; Thierry Marchal; Geert-Jan Maas; Jan Diepens
Publisher(s):
Elsevier BV
Tags:
Engineering; Energy
Most Recent Tweet View All Tweets
Most Recent Blog Mention
Most Recent News Mention
article description
A cycling peloton is the main group of cyclists riding closely together to reduce aerodynamic drag and energy expenditure. Previous studies on small groups of in-line drafting cyclists showed reductions down to 70 to 50% the drag of an isolated rider at same speed and these values have also been used for pelotons. However, inside a tightly packed peloton with multiple rows of riders providing shelter, larger drag reductions can be expected. This paper systematically investigates the drag reductions in two pelotons of 121 cyclists. High-resolution CFD simulations are performed with the RANS equations and the Transition SST-k-ω model. The cyclist wall-adjacent cell size is 20 μm and the total cell count per peloton is nearly 3 billion. The simulations are validated by four wind-tunnel tests, including one with a peloton of 121 models. The results show that the drag of all cyclists in the peloton decreases compared to that of an isolated rider. In the mid rear of the peloton it reduces down to 5%–10% that of an isolated rider. This corresponds to an “equivalent cycling speed” that is 4.5 to 3.2 times less than the peloton speed. These results can be used to improve cycling strategies.