The Mercedes-Benz Museum in Stuttgart, Germany, is a remarkable structure. Designed by Ben van Berkel and Caroline Bos of the Dutch firm UN Studio, the building received rave reviews when it opened in May of 2006. Influenced by Frank Lloyd Wright's Guggenheim Museum in New York, the building was described as "jet-age baroque" by The Guardian architecture critic Jonathan Glancey. "It twists and turns with breathtaking complexity," Glancey wrote in 2006, "clever as a conjuring trick."
The architects needed a bit of magic to bring the museum's open plan into compliance with fire codes. Like in the Guggenheim, the interior is one continuously unfolding space that spirals around a central atrium. As a consequence there could be no fire doors to contain smoke if a blaze broke out in one section of the building. To solve the problem, UN Studio hired the engineering firm Imtech to design a system that would draw smoke away from all areas of the museum, allowing people to escape.
The result is the world's largest man-made air vortex, a 112-foot-high tornado that automatically activates in the event of a fire, drawing smoke into the center of the atrium and moving it upward through an axial fan in the ceiling. An array of 144 outlets in the surrounding walls emit powerful jets of air to generate a central region of low pressure, just like in a real tornado. Imtech engineers perfected the design using computational fluid dynamic (CDF) simulations and laboratory models. The firm has created similar systems for airports in several German cities, including Düsseldorf and Hamburg. You can watch the tornado at the Mercedes-Benz Museum in action above.