German-Dutch Wind Tunnels

Dutch Olympians Edwin van Calker and Sybren Jansma are currently racing for gold in Vancouver in a new two-man bobsled that was comprehensively tested at German-Dutch Wind Tunnels (DNW).

This bobsled, which was entirely developed and constructed in the Netherlands, is a by-product of the TopBob project, an 18-month project that involved various organizations working together and in close collaboration with the Dutch National Bobsled & Skeleton Federation (Bob en Slee Bond Nederland). Over the coming years, the TopBob project aims to further professionalize the Dutch bobsled teams and close the knowledge gap that presently exists between the Dutch team and teams from leading bobsledding countries, such as Germany, the USA, Canada, Switzerland and Russia. The project had initially set its sights on the 2014 Winter Olympics in Sochi, Russia, where it would compete for the first time in a bobsled made entirely of Dutch materials. However, the project’s developmental process went faster than expected, thereby allowing a new Dutch bobsled to compete in this year’s Winter Olympics in Vancouver, Canada.

German-Dutch Wind Tunnels offers the possibility of using its Low Speed Tunnel (LST) for conducting aerodynamic research on sports-related activities. Such testing is done a few times a year, including for speed skaters, cyclists and now also bobsledders.

The new two-man bobsled underwent a series of wind tunnel tests, during which air resistance was measured and air flows visualized. Smoke or oil, which is illuminated by ultraviolet rays, is used to visualize air flows as they pass along an object. The degree of air resistance an object experiences depends on the amount of time, and the ways in which, an air flow ‘pushes’ against an object. Air flows will always eventually be released at a certain moment in time, but that moment must be delayed for as long possible. While a flow pushes against an object, the flow changes from laminar (low frictional air resistance) to turbulent (high frictional air resistance). The art lies in designing an object in such a way as to allow the air flow to remain in a laminar state for as long as possible, while also ensuring that before the laminar flow is released, the flow has indeed become turbulent and is eventually released.