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Freund, Jonathan B Pantano, Carlos Freund, Jonathan B Fischer, Paul Panesi, Marco Shields, Benjamin Thomas 2020-10-07T20:59:56Z 2020-10-07T20:59:56Z 2020-07-16 2020-08 Edge flames are a canonical two-dimensional flame structure appearing in more complicated combustion problems, such as lifted jet flames and in the dynamics of the growth and repair of flame holes in nonpremixed turbulent combustion. Typical theoretical configurations to study edge flames are unable to evaluate retreating edge flames with strong hydrodynamic-coupling. A new computational configuration is introduced which places the edge flame in a wedge-shaped counterflow with a mass sink, providing control over the position of the edge flame, and allowing access to stationary, hydrodynamically-coupled retreating flames (at high strain). This framework is first used to evaluate edge flames using a simple global one-step chemistry model and Fickian transport. This simple model is used to characterize the behavior of the resulting edge flames, including the relationship between flame speed and transverse strain rate and response to Lewis number variations. The details of the computational method will be discussed, including the underlying finite element method, the generation of boundary data, and the continuation of the flame through regions of varying transverse strain. This configuration is then applied to detailed ethylene-air combustion using a skeletal reduction of the USC Mech II combustion reaction model and a detailed transport model. The details of the ethylene-air edge flame are discussed, and comparisons are made between stoichiometric, fuel-lean, and fuel-rich compositions. Novel results characterizing the dilatation and vorticity near the flame front are provided, data which are necessary for the construction of potential flow approximations of hydrodynamically-coupled edge flames. Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2020-10-02 without embargo terms The student, Benjamin Shields, accepted the attached license on 2020-07-15 at 12:34. The student, Benjamin Shields, submitted this Dissertation for approval on 2020-07-15 at 12:46. This Dissertation was approved for publication on 2020-07-16 at 14:54. DSpace SAF Submission Ingestion Package generated from Vireo submission #15639 on 2020-10-02 at 15:13:56 Made available in DSpace on 2020-10-07T20:59:56Z (GMT). No. of bitstreams: 2 SHIELDS-DISSERTATION-2020.pdf: 72483665 bytes, checksum: 13668050bd1602085b35dfa15ef9a442 (MD5) LICENSE.txt: 4213 bytes, checksum: 6cd9f2ba59b7d2f929a54c2b1f2fb16d (MD5) Previous issue date: 2020-07-16 application/pdf http://hdl.handle.net/2142/108502 en Copyright 2020 Benjamin Thomas Shields Combustion Edge Flame Ethylene Nonpremixed Stationary edge flames in a wedge with hydrodynamic variable-density interaction text Thesis Mechanical Sci & Engineering Theoretical & Applied Mechans University of Illinois at Urbana-Champaign Dissertation Ph.D.