STOVL Test Facility

The Short Take-Off/Vertical Landing (STOVL) test facility simulates the impinging jet flow field that occurs in STOVL aircraft when in hover mode. The setup comprises a nozzle flush mounted in a circular plate (called lift plate), and a platform (called ground plane) mounted on a hydraulic lift. The lift plate simulates the undersurface of the STOVL aircraft, while the ground plane simulates the impingement surface. The nozzle to ground plane distance is varied using the hydraulic lift to move the ground plane up or down in order to simulate landing or takeoff. Both the lift plate and ground plane are instrumented with static pressure taps and slots used in making mean and unsteady pressure measurements.

High-pressure air is supplied to a settling chamber, and then issues from the nozzle. The nozzle is either converging or converging-diverging, resulting in sonic or supersonic flow respectively, when sufficient pressure is applied. Also, around the nozzle, there are smaller nozzles from which supersonic microjets 400mm in diameter issue. These microjets are used to control the flow characteristics. The characteristics of the flow fields generated with this setup are studied using data from various types of measurements/diagnostics. These include mean and unsteady pressure measurements, particle image velocimetry (PIV) and shadowgraph flow visualization.

This research is sponsored by the Air Force Office of Scientific Research (AFOSR).

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