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oai:www.ideals.illinois.edu:2142/16182 2023-07-10 col_2142_14787 col_2142_5131 com_2142_9630 com_2142_234 com_2142_5130

Matalon, Moshe Fogla, Navin 2010-05-19T18:40:00Z 2010-05-19T18:40:00Z 2010-05-19T18:40:00Z The effect of the Darrrieus Landau instability on a premixed flame in a turbulent environment is investigated using a model equation known as the Michelson Sivashinsky equation, in both one and two dimensions. The equation is externally forced with noise representative of weak turbulence in the flow and the response of the flame to both unstructured and structured noise is examined. It is found that for a given noise intensity there exists a threshold domain size, beyond which the instability amplifies the perturbations due to noise and causes the formation of wrinkles on the flame surface, leading to an increase in the propagation velocity. Scaling laws are proposed for the increase in propagation velocity with variations in noise intensity and a bifurcation parameter, which includes the effects of parameters such as the domain size, equivalence ratio and reaction rates. Self fractalization of the flame is observed at high noise intensities. Effects of the scale of noise, analogous to the scale of turbulence, are also examined and a resonant behavior is found to exist at certain scales. In the two dimensional case, cellular structures, similar to the ones observed experimentally on expanding spherical flames, are observed on the flame surface. Scaling laws similar to the one dimensional case are proposed. Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2010-04-27T14:40:45Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 1 Fogla_Navin.pdf: 11065924 bytes, checksum: 3b55ce9f86148ab9ddc9a51931c8e1f6 (MD5) 2010-5 Made available in DSpace on 2010-05-19T18:40:00Z (GMT). No. of bitstreams: 3 Fogla_Navin.pdf: 11065924 bytes, checksum: 3b55ce9f86148ab9ddc9a51931c8e1f6 (MD5) 1_Fogla_Navin.pdf: 11065925 bytes, checksum: 3076ca27b1d876157b160d344daf08b8 (MD5) license.txt: 4059 bytes, checksum: d5287275b18fe0bd1cb4ead79d49d3d6 (MD5) http://hdl.handle.net/2142/16182 en Copyright 2010 Navin Fogla Michelson Sivashinsky equation Darrieus–Landau instability turbulent flames self-fractalization Interplay between background turbulence and Darrieus-Landau instability in premixed flames via a model equation Mechanical Sci & Engineering 1917 Mechanical Engineering 0133 University of Illinois at Urbana-Champaign Thesis M.S. MS:Mechanical Engineerng -UIUC 10KS0133MS