120 Measurement of Drag Force on a Particle in a Particle Group Simulating Bicycles in a Cycle Road Race

Abstract

The paper deals with drag force acting on each cycle road racer in a cycle train. The drag force by the air is much larger than the friction force in a cycle road race and the evaluation of the drag force is important in working out the race strategy. In the experiment, a road racer was simulated by a sphere of 20 mm diameter, and the drag force on the sphere and the flow fields around it were measured at a test section in a passing water tank. The drag force was smallest at the fourth sphere in a line of 5 spheres. The effect of the line number was also shown. Because the Reynolds number of the sphere in the experiment is much smaller than that of the cycle road racer, the tendency of drag force in high Reynolds number was estimated by numerical calculation.