Advanced Optical Diagnostics/Modeling Platform for Plasma Assisted Combustion in Vitiated Air

ABSTRACT: Modern gas-turbine engines designs for the next-generation warfighter need to reduce exhaust gas temperatures to reduce effective thermal footprint thereby improving the mission capability. In such situations, high-altitude engine operation is often limited by the overall combustion efficiency, lean flame blow out (LBO) limit, and combustion instabilities that results in narrower operating window. One promising approach to increase the augmentor operational envelope is to utilize non-equilibrium plasma assisted combustion (PAC). Low-temperature plasma reactions can generate radical pools containing highly reactive species such as H, O, and OH in oxygen-depleted vitiated flow streams entering the augmentor. Achieving the full potential of PAC systems in vitiated air requires development of a more fundamental and detailed understanding of the basic chemistry and energy transfer processes, in particular temporal and spatial evolution of above key species and heat release rate. The current state-of-the-art, laser-spectroscopy-based plasma diagnostic tools are often plagued by laser-induced photochemistry, limited spatial dimensionality and slow data acquisition rates. We offer an integrated program in which a unique set of advanced diagnostics tools will be developed and utilized in order to produce a validated comprehensive plasma kinetics code for prediction of essential low temperature plasma properties in vitiated air streams. BENEFIT: The proposed research program will develop an advanced optical diagnostic/modeling platform for predicting of essential low temperature plasma properties in vitiated air streams, with unprecedented level of accuracy, spatial and temporal fidelity, and predictive capability. Such a unique toolkit will be a major step forward in implementing plasma-assisted combustion to new and existing augmentor design concepts, thereby, extending the operational envelop of gas turbine engines used in the modern warfighter. In particular, significant improvements are expected in both high-altitude, low-Mach number and low-altitude, high-Mach number operations with full afterburner operating conditions. The unique set of ultra-short-pulse laser-based revolutionary diagnostics techniques and cutting edge advanced plasma flow modeling capability in possession of the proposing research team is the key enabling technology for such breakthrough developments. In addition, the advancements of fundamental plasma studies proposed will have significant impacts in a wide array of applications related to national security and defense including, but not limited to, numerous weapons systems, plasma coated turbine blades, plasma-based systems for destroying chemical or biological hazards and plasma sources employed to decontaminate surfaces after a chemical spill or attack, as well as an array of applications in energy and environment, biotechnology and medicine.