The impact of arm-crank position on the drag of a paralympic hand-cyclist

• Published in: Computer methods in biomechanics and biomedical engineering 2019-03, Vol.22 (4), p.386-395
• Main Authors: Mannion, Paul, Toparlar, Yasin, Clifford, Eoghan, Hajdukiewicz, Magdalena, Andrianne, Thomas, Blocken, Bert
• Format: Article
• Language: English
• Subjects: Aerodynamic drag; Aerodynamics; Aerospace & aeronautics engineering; Arm; Arm - physiopathology; Athletes; Bicycling; Clocks; Computational fluid dynamics; Computer Simulation; Crank-rotation; Descent; Drag; Drag reduction; Eccentrics; Engineering, computing & technology; Hand; Hand - physiopathology; Hand-cycling; Hand-cycling; para-cycling; aerodynamics; computational fluid dynamics; arm-crank position; crosswinds; Humans; In-phase; Ingénierie aérospatiale; Ingénierie, informatique & technologie; Leg; Pressure; Research topics; Rotation; Scientists and engineers; Sports; Torso; Yaw; Yaw angles
• ISSN: 1025-5842; 1476-8259; 1476-8259
• DOI: 10.1080/10255842.2018.1558217

The aerodynamic features associated with the rotation of a cyclist's legs have long been a research topic for sport scientists and engineers, with studies in recent years shedding new light on the flow structures and drag trends. While the arm-crank rotation cycle of a hand-cyclist bears some resemblance to the leg rotation of a traditional cyclist, the aerodynamics around the athlete are fundamentally different due to the proximity and position of the athlete's torso with respect to their arms, especially since both arm-cranks move in phase with each other. This research investigates the impact of arm-crank position on the drag acting on a hand-cyclist and is applied to a hill descent position where the athlete is not pedalling. Four primary arm-crank positions, namely 3, 6, 9, and 12 o'clock of a Paralympic hand-cyclist were investigated with CFD for five yaw angles, namely 0°, 5°, 10°, 15°, and 20°. The results demonstrated that the 3 and 12 o'clock positions (when observed from the left side of the hand-cyclist) yielded the highest drag area at 0° yaw, while the 9 o'clock position yielded the lowest drag area for all yaw angles. This is in contrast to the 6 o'clock position traditionally held by hand-cyclists during a descent to reduce aerodynamic drag.