Variable Pressure High Speed Test Track

Miltec Missiles & Space Company and their subcontractor Secotec, Inc. are pleased to be invited to propose on a Phase II SBIR to develop, build and demonstrate a prototype of an innovative low cost ejector / diffuser system for the Holloman AFB High Speed Test Track (HHSTT). The innovative low cost ejector / diffuser system would be used for economically producing a high altitude simulation in a very long pressure chamber at HHSTT. The unique and challenging requirement here is that the operational pressure vessel total length will be thousands of feet and must be removable. The concept is low cost in that the prime movers (ejector motive fluid) are surplus turbojet engines that are available to the USAF at no cost. The maintenance costs would be minimal since the USAF has their own flight trained turbojet engine mechanics and support system. The concept would lay the groundwork for a variable pressure enclosure over the Holloman high-speed test track to simulate pressures corresponding from local ambient altitude up to altitudes of 100,000 feet. The requirement is that this very large vacuum vessel must be evacuated in a few hours time in order for a proposed sled test to be conducted economically. The proposed system would consist of portable "pressure vessel" segments that can be attached together to form a very long pressure vessel. The very long pressure vessel would then be connected to multiple regulated suction ports connected to a plenum, which is then connected to the ejector diffuser system. The innovative ejector / diffuser system proposed will be very energy efficient and easily maintainable. In addition, a technique to allow a sled to enter and exit the pressure vessel, while the sled is traveling at velocities up to 10,000 feet per second, without allowing changes in the pressure within the vessel has been conceptually developed in phase I. The prototype proposed herein would demonstrate the concept developed in phase I. The innovative design will allow the pressure vessel to maintain different pressures in different parts of the vessel to simulate flight from lower to higher, or higher to lower altitudes. This capability would be invaluable for air-breathing propulsion system development and testing.