Numerical simulations of the aerodynamics of a speedway motorcycle

This study presents a computational and experimental aerodynamic analysis of a speedway motor-cycle, focusing on drag reduction strategies to enhance performance. Using Computational Fluid Dynamics (CFD) simulations in STAR-CCM+ and wind tunnel experiments, the aerodynamic characteristics of the motorcycle and rider are investigated. Wind tunnel experiments were conducted to validate the CFD methodology, showing a deviation of 2% and 0.2% in drag area at 30 m∕s and 40 m∕s, respectively, confirming the reliability of the numerical model. The rider is identified as the primary drag contributor, accounting for over 50% of the total aerodynamic resistance, with significant contributions from the front fairing and exposed limbs. A comparative study of stationary and rotating wheels reveals that wheel rotation increases drag by 1.17%, primarily due to intensified low-pressure regions around the front wheel. Based on the findings, a new front fairing and hand cover design is proposed, achieving an 8.98% reduction in total drag by minimising high-pressure zones and wake turbulence. These results demonstrate the potential for aerodynamic improvements in speedway racing motorcycles, providing a foundation for future research on rider posture optimisation and advanced fairing designs.