journal article·2025-12-17Open access

Numerical Study on the Effect of Drafting Spacing on the Aerodynamic Drag Between Cyclists in Cycling Races

Fei Li, Lin Lu, Shuai Yang

Applied Sciences· Volume 15· Issue 24

Abstract

This study investigates the aerodynamic characteristics of drafting cyclists during 45° cornering through numerical simulations, and under the conditions of a vehicle speed of 15 m/s and a 45° body inclination, the SST k-ω turbulence model and grid independence verification (final grid count:12 million) are used to systematically analyze the distribution of velocity, vortex, pressure, and wall shear stress fields. The effects of riding velocity (5–25 m/s) and inter-rider spacing (100–500 mm) on aerodynamic drag were analyzed to reveal the underlying flow mechanisms. The results indicate that as velocity increases, airflow acceleration and boundary-layer shear intensify, leading to enhanced vortex shedding and elevated wall shear stress. In contrast, reduced spacing significantly strengthens wake coupling between riders, effectively lowering the frontal pressure and skin-friction drag of trailing cyclists. The drag reduction rate decreases monotonically with increasing spacing, with the second rider consistently achieving higher aerodynamic benefits than the third rider. Distinct from previous studies that predominantly focus on straight-line motion, this work fills a critical knowledge gap in sports aerodynamics and competitive cycling strategy. By elucidating the unique wake coupling mechanisms induced by body inclination, this study provides scientific evidence for optimizing drafting tactics specifically during high-speed technical cornering.
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Research context

OpenAlex topics: Aerodynamics and Fluid Dynamics Research · Sports Performance and Training · Sports Dynamics and Biomechanics

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

School of Sport and Physical Education, North University of China, Taiyuan 030051, China

School of Mechatronics Engineering, North University of China, Taiyuan 030051, China

Funding

National Natural Science Foundation of China · Natural Science Foundation of Shanxi Province · Shanxi Scholarship Council of China · Central Guidance Fund for Local Science and Technology Development

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