Enhancing Flow Migration and Reducing Emissions in Full Annular Ultra Compact Combustor
Document Type
Conference Proceeding
Publication Date
1-2-2016
Abstract
Since combustion efficiency in modern jet engines has stabilized in recent years, attention has turned to improving the combustor by improving the thrust-to-weight ratio by reducing the weight of the combustor while ensuring exhaust meets increasingly stringent government emission standards. The Ultra Compact Combustor is a means to fulfill these considerations. The combustion occurs under a g-load in the circumferential direction which maintains combustion efficiency while reducing byproduct production and axial combustor length. Previous experimental and analytic analysis optimized the combustion chamber flame characteristics with respect to altering the air flow split from a common upstream air source. The current issues for a UCC revolve around integrating this centrifugal flow combustor concept into a traditional axial turbojet. Current analysis has begun to quantify the effects of altering the geometry of the interface between the circumferential flow and the core flow, specifically on emissions and the exit temperature profile. The focus of this investigation was to enhance the migration of the hot combustion product radially across the hybrid vane. Variations of the geometry were quantified with temperature measurements and five species emission data recorded at the exit plane of the UCC. The max unburned hydrocarbon emission point values were shown to correspond with higher efficiency values. The addition of a radial vane cavity to the centerbody resulted in a temperature increase within the cavity and exit flow, which also caused increased NOx formation. By considering a series of lean-burn conditions, an emissions minima was found to occur between a Φ of 0.70-0.80.
Source Publication
54th AIAA Aerospace Sciences Meeting
Recommended Citation
Gilbert, N. A., Cottle, A. E., Polanka, M. D., & Goss, L. P. (2016). Enhancing Flow Migration and Reducing Emissions in Full Annular Ultra Compact Combustor. 54th AIAA Aerospace Sciences Meeting, Session: Combustion III, AIAA 2016-2122. https://doi.org/10.2514/6.2016-2122
Comments
This conference paper is available through subscription or purchase from the publisher, AIAA, using the DOI link below.
Conference session: Combustion III
Author notes: Andrew Cottle was an AFIT PhD candidate at the time of this conference. (AFIT-ENY-DS-16-D-037, December 2016)
Nicholas Gilbert was an AFIT graduate student (Masters) at the time of this conference. (AFIT-ENY-MS-16-M-211, March 2016)