Research & Technology

Short Take-Off and Vertical Landing (STOVL) Jet Facility

The Short Take-Off and Vertical Landing (STOVL) test facility simulates the impinging jet flow field that occurs in STOVL aircraft when in hover mode. A typical setup comprises a nozzle flush mounted in the circular lift plate simulating the undersurface of the aircraft, and a rectangular plate as ground plane. In order to simulate different heights above the ground, the ground plane is mounted on a hydraulic lift and can be moved relative to the lift plate. The nozzle is either converging or converging-diverging, resulting in sonic or supersonic flow respectively, when sufficient pressure is applied. An array of microjets, placed appropriately near the nozzle exit is used to control the flowfield in and around impinging jets.

Operational/Test Capabilities

Mach Number = 0.5 - 2.5
To= 70 - 800° F
dJet = 25.4 mm (Typ.)
NPR = Under-ideal-over expanded
Temperature Ratio = 1.0 - 1.6
Height/dJet = 2- 40
Run duration = 15 min – 20 min

Diagnostics and Test Hardware

Near Field noise measurements using Microphones
Steady and Unsteady pressure measurements on lift plate and ground plane
Temperature profiles on measurement surfaces
Flow visualization using shadowgraph and schlieren techniques
Planar and Stereoscopic Particle Image
Velocimetry
High Temperature Unsteady Pressure Probes
Labview based facility operation and data acquisition programs
Signal conditioning system including amplifiers and band-pass filters
High speed Simultaneously sampling data acquisition cards

R& D Activities

Supersonic Impinging jet noise characterization
Active control to reduce impinging jet noise using high momentum microjets
- Air/Gas jet injection
- Steady/pulsed microjet control
High temperature impinging jet characteristics and control
Research supported by AFOSR