Analysis of Aerodynamic Drag on Cycling Based on Complementary Numerical and Experimental Studies

Abstract

Aerodynamic drag is the main opposing force that a cyclist has to overcome when cycling on level ground at moderate-to-high speeds. Therefore, the aerodynamic study of the bike-cyclist set has been identified as a key factor for the analysis and improvement of performance. Although there are many reference aerodynamic studies, for the specific analysis of a bike-cyclist set it is necessary to take into account the particular influence of the cyclist’s body shape, cyclist position and cycling equipment on aerodynamic drag. In addition, there are quantitative studies focused on analyzing aerodynamic drag using numerical and experimental methodologies; nonetheless, these studies are generally not complementary or comparative. The aim of this paper is to present the first stage of a current work that seeks to develop a complementary methodology for the aerodynamic drag analysis using numerical and experimental studies. In this stage, a numerical study based on Computational Fluid Dynamics (CFD) is presented. A digitalized cyclist body model is analyzed while the mesh characteristics and the results of the CFD simulations are addressed. On the other hand, field experimental tests were carried out by the same cyclist to determine the power demand at two cyclist’s body positions. A method for monitoring the cyclist’s body position in order to achieve repeatable positions during experimental trials is presented. Complementary information for the aerodynamic evaluation is obtained through the numerical and experimental studies, and the aerodynamic drag area results from both approaches is compared.