Aerodynamic analysis of uphill drafting in cycling

Some teams aiming for victory in a mountain stage in cycling take control in the uphill sections of the stage. While drafting, the team imposes a high speed at the front of the peloton defending their team leader from opponent’s attacks. Drafting is a well-known strategy on flat or descending sections and has been studied before in this context. However, there are no systematic and extensive studies in the scientific literature on the aerodynamic effect of uphill drafting. Some studies even suggested that for gradients above 7.2% the speeds drop to 17 km/h and the air resistance can be neglected. In this paper, uphill drafting is analyzed and quantified by means of drag reductions and power reductions obtained by computational fluid dynamics simulations validated with wind tunnel measurements. It is shown that even for gradients above 7.2%, drafting can yield substantial benefits. Drafting allows cyclists to save over 7% of power on a slope of 7.5% at a speed of 6 m/s. At a speed of 8 m/s, this reduction can exceed 16%. Sensitivity analyses indicate that significant power savings can be achieved, also with varying bicycle, cyclist, road and environmental characteristics.

Aerodynamic Effect of Wheel Fairings on the Wake of a Formula One Car

The open-wheeled configuration of Formula One cars has been known to create unfavourable aerodynamic conditions for overtaking during races. New aerodynamics regulations are set to come into effect by the 2022 season. Early concepts suggested that covering the wheels of a car are amongst the aerodynamic design changes to be implemented. This is in contrast to the traditional open-wheeled configuration. This study aims to evaluate the effect that these fairings have on the behaviour of the wake behind the car. This has been achieved through computational fluid dynamics (CFD) studies which surveyed the flow in the wake, that determined any changes that are added by these fairings. The fairings were found to have altered the structure of the wake, by changing the size of the regions of low-speed airflow at different positions behind the car.

Aerodynamic Effect of Wing Mirror Usage on the Solaris 7 Solar Car and Demobil 09 Electric Vehicle

This study focuses on the aerodynamic performances of two vehicles by Dokuz Eylul University Solaris Solar Car Project Team. The first vehicle (S7) is a solar-powered vehicle that is designed for World Solar Challenge and the second (D9) is an electric vehicle which is designed for Tubitak EV Challenge. Both vehicles are manufactured using polymer composites and challenged in mentioned races. In this research, a formal optimisation technique based on computational fluid dynamics (CFD) is used to determine the efficient aerodynamic structures under various scenarios. Results clearly show that strategists of the racing teams should take intoaccount the aerodynamic structure of the racing car. Especially before the races which based on efficiency, the apex line is determined, and mirrors should be replaced by back view camera.