Date of Award
Master of Science
Department of Aeronautics and Astronautics
Marc D. Polanka, PhD.
A major thrust of turbine engine research is to improve both efficiency and thrust-to-weight ratio of the engine. A promising solution to this challenge is the Ultra-Compact Combustor (UCC). The UCC shortens the axial length of the combustor by performing combustion circumferentially on the outer diameter of the engine. The reduction in axial length yields significant weight savings and increases the thrust-to-weight ratio. The design also increases combustion efficiency by performing the combustion in a centrifugally loaded environment which allows unreacted particles to remain in the combustor sufficiently long enough to become combustion products. The Air Force Institute of Technology (AFIT) and the Air Force Research Laboratory (AFRL) have been jointly researching the fundamental dynamics of the UCC. To aid in integrating the UCC into a turbine engine, the current objective is to desensitize the exhaust characteristics of the combustor to changes in operating parameters. The following report documents modifications to the AFIT sectional test rig to improve its replication of the AFRL full annulus. High speed video was captured to document flame shape, location, intensity, and stability within the core section. Carbon monoxide, carbon dioxide, oxygen, nitrous oxides, and unburnt hydrocarbon emissions measurements were recorded to quantify the combustors exhaust constituents. A novel vane concept was implemented to desensitize the flame shape, location, intensity, and its exhaust products with changes in operating parameters. The design represents the next step toward creating a UCC vane that can migrate the flow effectively and consistently from the UCC cavity into the core flow. Furthermore, this vane concept represents the first attempt at a design that can be effectively cooled for application in a realistic turbine engine
DTIC Accession Number
Parks, Adam K., "Desensitizing Flame Structure and Exhaust Emissions to Flow Parameters in an Ultra-Compact Combuster" (2012). Theses and Dissertations. 1060.