Jet engine turbine (3D xray blue transparent)

Low Emissions Lean Pre-Mixed, Pre-Vaporized Combustion Technology for Subsonic Civil Transport

Project Number: 098
Category: Aircraft Technology Innovation

Lean pre-mixed pre-vaporized (LPP) combustion is a key enabling technology to further reduce NOx and non-volatile particulate matter (nvPM) emissions from aeronautical gas turbine engines, while achieving the necessary durability and robustness. However, achieving practical LPP combustion is challenging due to the need to rapidly vaporize and mix fuel, stabilize LPP flames across a wide operating envelope, and prevent unwanted combustion dynamics. Furthermore, the ability of current design methodologies to predict the operability and emissions of these combustors is unproven. Previous work during ASCENT Project 74 demonstrated positive results for an LPP combustor configuration at the conditions found in engines for supersonic transport aircraft, and also encouraged further exploration at conditions relevant for the conventional subsonic fleet. This project will characterize the emissions and operability of the LPP combustor at key operating points for such subsonic aircraft engines, including low power (idle, taxi), cruise, and approach. High-quality experimental data at relevant conditions will be coupled to development/validation of computational fluid dynamics (CFD) simulations and reduced order models. This forms a key first step in the development of both the LPP combustor technology and validated design tools for subsonic aircraft engine conditions.


This project will generate critical data and validated design methods needed to predict the behavior of LPP combustion technology at engine conditions relevant to the conventional subsonic transport aircraft fleet. This, in turn, will guide design decisions that ultimately enable low-emission, robust, and stable combustion for subsonic aircraft engines. Expected long-term benefits include lower emissions NOx and nvPM across the flight mission, with simultaneous reductions in engine development times/costs. Additionally, the program will support workforce development and training of students in state-of-the-art methods for combustor measurement and simulation, while strengthening connections between industry and academia.

Last updated 7/20/2023

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