Transient Corona Discharges for Ignition and Flameholding in an Afterburner Environment
Abstract
The project goal is to assess the feasibility of using transient corona discharges as a substitute or booster of current flameholder elements in afterburners. Afterburners are ubiquitously used in Sea-based Aviation (SBA). The vision of this project is that transient corona discharges can improve the performance of afterburners as follows: i) reducing detectability, increasing efficiency, and allowing for more compact elements; ii) extending combustion static stability limits; and (iii) providing a broadband control actuation strategy to address dynamic stability challenges. The project goal will be achieved through two main research objectives: 1) Derive the dependencies of transient corona discharges with the afterburner environment, including the plasma regime, the spatial structure of the plasma-activated zone, the total energy deposition, and the energy pathways and chemical kinetics activated by the plasma; and 2) Determine the operational envelope and expected authority of transient corona discharges in extending the static limits of combustion in conditions relevant to afterburners. The first contribution of the project will be a characterization of transientcorona discharges in high temperature vitiated flow. These experimental studies will reveal the electrical properties of the discharge, including the energy deposition and energy deposition pathways, as well as the discharge morphology and geometry. The chemical activity triggered by the corona will be explored by numerical modeling of streamer discharges by decoupling the streamer dynamics from the chemical kinetics. The second contribution of the project will be the development of a framework to assess the authority andefficacy of transient corona discharges for ignition and flameholding in afterburner conditions. The novelty of the approach is to account for the filamentary structure of the discharges, including inflammation and multipoint inflammation strategies. The work will include the development of a numerical model of inflammation considering variable size ignition kernels and both thermal and nonthermal energy pathways. An experimental study using two burners in series, representing main burner and afterburner, will demonstrateignition and flameholding in an afterburner environment. The results from this work will be leveraged to initiate discussions with interested parties within ONR and industry for future testing in a real-scale afterburner. The responsibilities of ONR extend all the way from sea floor to space, and in particular SBA constitutes the fifth National Naval Responsibility. SBA presents unique challenges in their propulsion systems and in particular the engine main burners and afterburners. In particular, their very broad operational envelope presents unique challenges in terms of ensuring stable operation from slow approach maneuvering to robust waveoff and bolter capabilities, including very high thrust response to meet these requirements in normal and emergency situations. Moreover, stealth aircraft will become more common, introducing new challenges in the detectability of the engines. Plasma-assisted technologiesintroduce an extra knob to address challenges in combustion, and these technologies will play a key role in the future of aerospacepropulsion, and in particular SBA propulsion.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 09, 2021
- Source ID
- N000142112571
Entities
People
- Carmen Guerra Garcia
Organizations
- Massachusetts Institute of Technology
- Office of Naval Research
- United States Navy