Improving fundamental understanding of turbulent combustion in relevant regimes is important for many power and propulsion applications with significant impact and broad relevance to a range of national and international grand challenges.  The challenges include achieving a sustainable energy future through increasing efficiencies of power, propulsion, and transportation systems; attaining a clean environment through managing pollutant emissions; and enhancing national security through pursuing innovative defense technologies.  Power and propulsion systems which rely upon turbulent combustion are pervasive across the Department of Defense and United States Air Force for current and next-generation applications such as gas turbine combustors, inter-turbine combustors, augmentors, rotating detonation engines, scramjets, and rockets.

     The primary objective associated with this topic involves performing fundamental research or advanced technology development related to the broad areas of energy and combustion science.  The experimental or computational work should focus on relevant configurations operating under relevant conditions.  Specific turbulent reacting flows of interest include swirl stabilized flames, cavity stabilized flames, bluff-body stabilized flames, and detonations.  Relevant conditions typically involve high pressures, high temperatures, high speed compressible flows (i.e. high Mach numbers), high turbulence intensities (i.e. high Reynolds numbers), and multi-component liquid fuels.  Research opportunities include but are not limited to the following general topics: (1) fundamental interactions between turbulence, chemical kinetics, flame structure, and flame dynamics; (2) near-limit combustion phenomena such as ignition, extinction, and thermo-acoustic instabilities; (3) advanced combustion technologies for enhancing ignition under low-pressure low-temperature conditions, improving flame stabilization in high-speed compressible flows, or minimizing thermo-acoustic instabilities; (4) spray combustion of multi-component liquid fuels; (5) combustion modeling, direct numerical simulations (DNS), or large eddy simulations (LES); or (6) thermodynamic cycle analyses.

     The research and development is expected to align with ongoing work being conducted at the Air Force Research Laboratory Aerospace Systems Directorate Turbine Engine Division Combustion Branch.  The Combustion Branch provides access to state-of-the-art experimental and computational resources including the Combustion Research Complex, High Pressure Combustion Research Facility, and Supercomputing Resource Center.  The experimental facilities are capable of supplying large amounts of air and fuel at the pressures, temperatures, and flow rates necessary to achieve relevant conditions in representative single-element benchmark configurations.  Experimental capabilities include but are not limited to emissions sampling; hot-wire anemometry; high-speed broadband, filtered chemiluminescence, and mid-infrared imaging; hydroxyl and formaldehyde planar laser induced fluorescence (PLIF) imaging; particle image velocimetry (PIV); and phase Doppler particle anemometry (PDPA).  Computational capabilities include in-house and commercial large eddy simulation (LES) codes and high-performance computing (HPC) systems.

Keywords:

Combustion; Detonation; Propulsion; Power generation; Combustion experiments; Combustion modeling; Computational fluid dynamics (CFD); Large eddy simulations (LES); Gas turbine engines; Augmentors

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral and Senior applicants