The Mercedes-Benz Museum is home to more than just automobiles. In 2007, the Guinness Book of Records gave it recognition for housing the "strongest artificially generated tornado in the world." The 34.4 meter high (that is 37.2 yards to those metrically challenged) vortex was not designed as an attraction, but to channel smoke out of the building in the event of a fire. In the event of fire, 144 outlets located along the core walls inject air into the interior courtyard of the Mercedes-Benz Museum. The 100-feet twister takes around seven minutes to materialize, drawing smoke out of the building"s corridors and funnelling it upwards and out an exhaust vent on the roof.
Due to the open-plan structure of the Mercedes-Benz Museum, the various exhibition areas are connected to each other without any fire zones via an interior courtyard and ramps. From the perspective of smoke elimination this presented a challenging task that could not be implemented through conventional fluid mechanics. It was necessary to take a new approach, and so a globally unique smoke elimination system was developed especially for the Mercedes-Benz Museum.
This procedure uses the principle of the tornado force, which has a devastating effect under natural conditions, to create a controlled life-saving form of fluid mechanics that opens up new architectural possibilities.
http://blog.mercedes-benz-passion.com/2010/08/1-woche-der-helfer-tornado-im-mercedes-benz-museum/