The former Belgian top cyclist Johan Museeuw once stated: “Crashing is part of cycling as crying is part of love.” Indeed, probably every elite cyclist has experienced in-race crashes that put him or her in the hospital. But recently, things seem to have become much worse. In the past two years, many prestigious elite races have been stained by serious crashes between riders and in-race motorcycles. The tragic culmination so far of these crashes was reached on 27 March 2016, when Belgian rider Antoine Demoitié got hit by a motorcycle in the race Gent-Wevelgem and died later in hospital due to his injuries. Later, on 28 May 2016, 19 cyclists were involved in a major crash with two motorcycles, which put Belgian rider Stig Broeckx in hospital in a coma. Continue reading
This Sunday one of the most popular sporting events for tens of million people around the world begins. The Tour de France starts in Utrecht, the Netherlands. We will again see the world’s best top athletes fighting for the stage victory every day. We’ll admire them as they climb the steepest slope at an amazing speed and be impressed to see them completing a time trial at an average speed above 50 km/h. Throughout the past years, the regulations have continuously improved to guarantee a clean and fair race. As an example, during time trials, neither cars nor motorbikes are allowed in front of the cyclists as this would obviously reduce air resistance. Similarly, if a cyclist is catching up to the one ahead, they must stay on different sides of the road. However, there is no regulation to prevent a vehicle from following the athlete as it is commonly believed that a car riding behind a cyclist cannot influence him.
But is this really true?
Anybody who has bicycled with a group on a windy day has enjoyed the benefit of sheltering behind the person in front of them. Similarly, it is well-known in cycling that drafting riders (cyclists who ride behind another cyclist) benefit from the slipstream of the front rider. That is why in races, like the Tour de France, cyclists try to ride in a line to save strength for the final part of the race.
A collaborative research effort was conducted to study cycling aerodynamics with our colleagues at KU Leuven (Thijs Defraeye and Peter Hespel), the Flemish Cycling Union (Erwin Koninckx), ETH Zurich (Jan Carmeliet) and the Dutch-German Wind Tunnels (Eddy Willemsen). We are all now continuing these studies with the ANSYS CFD code to look into the aerodynamic effects in time trial races and in full peloton sprints. Continue reading