Investigation of Combustion Instability in Augmentors Using High-Speed PIV and PLIF

The objective of the proposed Phase-I research effort is to assess the feasibility of performing high-speed (1-5 kHz) particle-image velocimetry (PIV) and planar laser-induced fluorescence (PLIF) for understanding combustion stability and related phenomena in gas-turbine augmentors. Initial demonstration measurements will be performed in cold and heated air flows using PIV and acetone/biacetyl PLIF at 1 kHz, with the goal of capturing coherent structure dynamics and understanding their role in affecting combustion stability in augmentor flows. Extension of such measurements to higher repetition rates and for species such as the hydroxyl radical (OH) will also be evaluated. This research effort will be used to design a second generation system for application of high-speed PIV and PLIF of fuel and OH in a realistic augmentor test rig during the Phase-II period. Successful Phase-I and Phase-II efforts will lead to the development of a prototype high-speed diagnostic system for PIV and PLIF of fuel and combustion products, to be installed within an augmentor test facility of AFRL’s choice.