This project looks at the complex physics of combustor liner flows to help aviation engineers develop cleaner, more efficient engines. Utilizing earlier results on the characteristics of multi-hole cooling flow on the transition piece, the part of the combustor liner that connects the main combustion zone and turbine, current simulations will use wall-modeled large-eddy simulations (LES) to analyze flow in single and multi-cup combustors.

An in-depth study of the detailed geometries of combustor systems requires computational fluid dynamics (CFD) resolutions achievable only on massively parallel computing platforms, such as Mira. This collaborative effort has investigated four geometries, thus far, using Cascade Technologies’ CFD code, CharLES low-Mach “Helmholtz” solver, which performs reacting LES and reproduces the important interactions between chemistry, turbulence, and acoustics that occur in real-world gas turbine engines.

Understanding and predicting the aero-thermal flow field in combustors is a key step in designing and optimizing the architecture for better fuel efficiency, lower emissions and better performance. The first group of calculations used LES to model the behavior of an idealized configuration representative of combustor liners. This has enabled modelers to generate high-fidelity datasets that will be used to improve low-fidelity models available to designers. Next, simulations will use wall-modeled LES to analyze the flow in single- and multi-cup combustors.

Researchers will apply the same approach to a more complex configuration, involving a larger domain and more realistic flow characteristics. They will employ the results on an actual multi-cup General Electric rig, providing a vehicle with which to test the improved models developed in the first two steps of the program. This affords designers a better understanding of the complex unsteady processes governing the aerothermal field around combustor liners.