{"662124":{"#nid":"662124","#data":{"type":"event","title":"PhD Defense by Askar Kazbekov","body":[{"value":"\u003Cp\u003EAskar Kazbekov\u003Cbr \/\u003E\r\n(Advisor: Prof. Adam M. Steinberg) will defend a doctoral thesis entitled,\u003Cbr \/\u003E\r\nInter-Scale Energy Transfer in Turbulent Premixed Combustion\u003Cbr \/\u003E\r\nOn\u003Cbr \/\u003E\r\nFriday, October 28 at 4 p.m.\u003Cbr \/\u003E\r\nFood Processing Technology Building, Auditorium 102 https:\/\/teams.microsoft.com\/l\/meetup-\u003Cbr \/\u003E\r\njoin\/19%3ameeting_YzBlNjJjMTgtY2IyMC00Y2FlLWIzNWEtYWZmZjQzZTNiNDA1%40thread.v2\/0?cont\u0026nbsp;\u003Cbr \/\u003E\r\next=%7b%22Tid%22%3a%22482198bb-ae7b-4b25-8b7a-\u0026nbsp;\u003Cbr \/\u003E\r\n6d7f32faa083%22%2c%22Oid%22%3a%226672f38c-a0a6-4478-b20b-ebb645568f34%22%7d\u003Cbr \/\u003E\r\nAbstract\u003Cbr \/\u003E\r\nTurbulent premixed combustion is widely used for energy conversion in power generation and\u0026nbsp;\u003Cbr \/\u003E\r\npropulsion devices. However, our understanding of the underlying fluid dynamics, combustion, and\u0026nbsp;\u003Cbr \/\u003E\r\ntheir interaction is still incomplete. The complexity of turbulent combustion arises from the\u0026nbsp;\u003Cbr \/\u003E\r\nnon-linear, multi- scale, and multi-physics nature of the problem, which involves interactions\u0026nbsp;\u003Cbr \/\u003E\r\nbetween fluid dynamic and chemical processes across a myriad of length and time scales. The\u0026nbsp;\u003Cbr \/\u003E\r\nexisting literature demonstrates that the dynamics of reacting turbulence does not necessarily\u0026nbsp;\u003Cbr \/\u003E\r\nfollow the same phenomenology as in non- reacting incompressible turbulence. One of the key\u0026nbsp;\u003Cbr \/\u003E\r\ndifferences in reacting and compressible flows is the reversal of the classical turbulent energy\u0026nbsp;\u003Cbr \/\u003E\r\ncascade in a process termed as \u0026lsquo;backscatter\u0026rsquo;. Moreover, backscatter was shown to potentially depend\u0026nbsp;\u003Cbr \/\u003E\r\non the magnitude of the pressure gradients across the flame; this is reflected in the\u0026nbsp;\u003Cbr \/\u003E\r\nsub-filter-scale pressure-work. Previous studies have predominantly focused on flames in\u0026nbsp;\u003Cbr \/\u003E\r\nhomogeneous isotropic turbulence (HIT), in which the pressure gradients are associated with the\u0026nbsp;\u003Cbr \/\u003E\r\nflame and turbulence themselves. In contrast, practical combustors have mean pressure fields\u0026nbsp;\u003Cbr \/\u003E\r\ngenerated by the flow, which can induce significantly different turbulence dynamics as compared to\u0026nbsp;\u003Cbr \/\u003E\r\nnon-reacting turbulence. The presented research explores the conditions at which energy backscatter\u0026nbsp;\u003Cbr \/\u003E\r\noccurs in an aerospace relevant configuration and attempts to identify the underlying physical\u0026nbsp;\u003Cbr \/\u003E\r\nmechanisms that have a leading order impact on these processes. This is done through systematic\u0026nbsp;\u003Cbr \/\u003E\r\nvariation of the global equivalence ratio, the jet flow velocity, and the magnitude of the mean\u0026nbsp;\u003Cbr \/\u003E\r\npressure field. The impact of these controlling parameters on turbulence production and energy\u0026nbsp;\u003Cbr \/\u003E\r\nbackscatter is assessed through the analysis of filtered kinetic energy transport equations.\u0026nbsp;\u003Cbr \/\u003E\r\nTomographic particle image velocimetry (TPIV) and planar laser induced fluorescence (PLIF) are used\u0026nbsp;\u003Cbr \/\u003E\r\nto measure the 3D velocity fields and planar distribution of formaldehyde, respectively; the\u0026nbsp;\u003Cbr \/\u003E\r\nrelevant thermodynamic properties (e.g., density and progress variable) are estimated from PLIF\u0026nbsp;\u003Cbr \/\u003E\r\ndata. Ultimately, this work provides both an assessment of the validity of current turbulence\u0026nbsp;\u003Cbr \/\u003E\r\nmodeling paradigms employed in aerospace relevant combustion, as well as the data necessary to\u0026nbsp;\u003Cbr \/\u003E\r\ndevelop and validate new models if required.\u003Cbr \/\u003E\r\nCommittee\u003Cbr \/\u003E\r\n\u0026bull; \u0026nbsp;Prof. Adam M. Steinberg \u0026ndash; School of Aerospace Engineering (advisor)\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026bull; \u0026nbsp;Prof. Tim C. Lieuwen \u0026ndash; School of Aerospace Engineering\u003Cbr \/\u003E\r\n\u0026bull; \u0026nbsp;Prof. Joseph Oefelein \u0026ndash; School of Aerospace Engineering\u003Cbr \/\u003E\r\n\u0026bull; \u0026nbsp;Prof. Jerry M. Seitzman \u0026ndash; School of Aerospace Engineering\u003Cbr \/\u003E\r\n\u0026bull; \u0026nbsp;Prof. Ellen Yi Chen Mazumdar \u0026ndash; School of Mechanical Engineering\u003Cbr \/\u003E\r\n\u0026nbsp;\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Inter-Scale Energy Transfer in Turbulent Premixed Combustion"}],"uid":"27707","created_gmt":"2022-10-13 19:57:57","changed_gmt":"2022-10-13 19:57:57","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2022-10-28T17:00:00-04:00","event_time_end":"2022-10-28T19:00:00-04:00","event_time_end_last":"2022-10-28T19:00:00-04:00","gmt_time_start":"2022-10-28 21:00:00","gmt_time_end":"2022-10-28 23:00:00","gmt_time_end_last":"2022-10-28 23:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"78771","name":"Public"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}