WTTECH.CZ
Free fall Simulation
Three different types of Vertical Wind Tunnels for Free Fall Simulation are offered by WTtech.CZ in the Czech Republic, as John Rosen describes
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ontActs in 1989 with a group of parachutists triggered
The Conventional Closed Circuit Wind Tunnel
The Double Return Leg Tunnel
The Axis Symmetric Multi Fan Free Fall Simulator
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the interest in developing wind tunnels with a purpose of improving the conditions for free fall simulation. In early facilities, open or half-open test sections had a very peaky velocity distribution and in open-circuit tunnels the external weather conditions heavily influenced the bad flow quality of these tunnels.
After training in USA and Europe, a group of parachutists from Gothenburg, Sweden described a number of faults in most of these foreign facilities, faults that easily could be cured or improved by applying modern wind tunnel technology. The first design proposals addressing these shortcomings were published in 1992 in a paper presented during a Swedish Civil Aviation Group (SCAG) exposition and meeting in Budapest. In this proposal, it was demonstrated how a four-fan system enables building height to be reduced compared to conventional layouts. Another multi-fan, compact layout was subsequently improved by means of computational fluid dynamics (CFD) studies. One further advantage of this axis-symmetric design with ten fans was that an amphitheater could be installed on top of the tunnel where spectators can observe the individuals which are subject to free fall in the “diving” chamber. After further redesigns carried out in the middle of the first decade of a new century, WTtech.CZ, originally launched by Czech skydivers, offers primarily three different types of Vertical Wind Tunnels – Free Fall Simulators (VWT-FFS).
The Vertical Wind Tunnel - Free Fall Simulator VWT-FFS-4372 erection in prague (flying chamber diameter 4.3m, nominal max. airspeed 72 m/s)
WIND TUNNEL INTERNATIONAL | 2010