DESIGN AND PERFORMANCE OF A HYPERSONIC WIND TUNNEL

A moveable block planar nozzle wind tunnel design from the University of Michigan in 1955 was shown with previous analysis to operate between Mach 1 and at least Mach 6.3 for mid-size test sections, with continuous variation in Mach number and accounting for limitations governed by supply temperature and pressure, liquefaction, flow rate, and flow quality for a desired dynamic pressure or Reynolds number. The moveable block planar nozzle design allows for continuous variation of Mach number, based on a Method of Characteristics solution to a convergent-divergent nozzle with a boundary layer correction. The present work summarizes the design considerations and hardware performance requirements for such a tunnel in the blowdown configuration, with a comparison between cold and hot operation for various test section sizes and supply conditions. The flow quality is compared between a two planar nozzles and an axisymmetric nozzle for a 12x12[in] test section, the effect of physical scaling on flow quality and boundary layer encroachment is investigated across scales of 1x1" to 12x12" test sections at Mach 5, and the merits of planar nozzle aspect ratios greater than unity are presented and discussed.