{"690152":{"#nid":"690152","#data":{"type":"event","title":"PhD Proposal by Ari Jain","body":[{"value":"\u003Cp\u003EStudent Name: Ari Jain\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EAdvisor: Dr. Adam Steinberg\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EMilestone: PhD Thesis Proposal\u003Cbr\u003E\u003Cbr\u003EDegree Program: Aerospace Engineering\u003Cbr\u003E\u003Cbr\u003ETitle: Flame Structure, Operability, and Diagnostic Development in Lean Premixed Prevaporized Gas Turbine Combustors\u003Cbr\u003E\u003Cbr\u003EAbstract: This proposal investigates flame structure, operability, and diagnostic development in lean premixed prevaporized (LPP) gas turbine combustors across operating regimes relevant to future low-emissions aircraft engines. LPP combustion offers a pathway to reduced NOx and non-volatile particulate matter emissions by burning globally lean. However, practical implementation is limited by competing operability challenges, including fuel-dependent mixing and vaporization effects, lean blowoff, and high-power failure modes such as flashback and upstream flame holding. This work addresses these challenges through three coordinated experimental campaigns using advanced optical diagnostics in both industrially relevant and laboratory-scale combustors. The first campaign examines how conventional Jet-A, hydroprocessed esters and fatty acids (HEFA) sustainable aviation fuel, and a 50\/50 Jet-A\u2013HEFA blend influence spray behavior, flame structure, and lean operability in a multi-element LPP combustor. Measurements using OH planar laser-induced fluorescence (PLIF), OH* chemiluminescence (CL), Mie scattering, and phase Doppler particle analysis are used to connect fuel physical properties to droplet penetration, vaporization, flame topology, and blowoff behavior. Preliminary results show that HEFA produces shorter liquid-fuel penetration depths than Jet-A and the blend, consistent with its lower density, viscosity, surface tension, and distillation characteristics. These results provide a basis for determining whether fuel-dependent spray and mixing differences significantly alter global lean blowoff behavior or primarily affect local flame structure and intermittency. The second campaign investigates pilot\u2013main flame interactions in a practical multi-element LPP combustor by independently varying pilot and global equivalence ratios while acquiring measurements across multiple radial planes. OH\/kerosene PLIF, Mie scattering, and high-speed OH* or CH* CL are used to identify how the central pilot modifies the surrounding bluff-body-stabilized main flames. This campaign is designed to determine whether the pilot primarily stabilizes the mains by supplying hot products and chemically active species to the main-flame recirculation zones, and whether global lean blowoff limits are more strongly controlled by main-flame conditions than by pilot equivalence ratio within the pilot\u2019s own stability limits. The third campaign develops laser-induced phosphor thermometry (LIPT) for spatially and temporally resolved wall-temperature measurements under high-power takeoff conditions. Candidate phosphor coatings will be selected, calibrated, and evaluated for lifetime-based thermometry in a medium-pressure burner. LIPT measurements, combined with chemiluminescence imaging, will be used to identify localized wall-temperature signatures associated with abnormal flame\u2013wall interactions and potential upstream flame holding. Although the medium-pressure burner cannot fully reproduce the thermal and optical environment of high-power testing, it provides a controlled platform for developing diagnostic capability that can later be extended to more severe gas-turbine operating conditions. Together, these campaigns aim to clarify how fuel properties, pilot\u2013main coupling, and wall thermal response influence LPP combustor operability. The expected outcome is an improved physical understanding of flame stabilization and failure mechanisms in practical lean-burn combustors, along with diagnostic tools needed to characterize these processes across operating regimes.\u003Cbr\u003E\u003Cbr\u003EDate and time: 2026-05-15, 2:00 PM\u003Cbr\u003E\u003Cbr\u003ELocation: Montgomery Knight Room 317\u003Cbr\u003E\u003Cbr\u003ECommittee:\u003Cbr\u003EDr. Adam Steinberg (advisor), School of Aerospace Engineering\u003Cbr\u003EDr. Ellen Mazumdar, School of Mechanical Engineering\u003Cbr\u003EDr. Benjamin Emerson, School of Aerospace Engineering\u003Cbr\u003E\u003Cbr\u003E\u0026nbsp;\u003C\/p\u003E","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EFlame Structure, Operability, and Diagnostic Development in Lean Premixed Prevaporized Gas Turbine Combustors\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Flame Structure, Operability, and Diagnostic Development in Lean Premixed Prevaporized Gas Turbine Combustors"}],"uid":"27707","created_gmt":"2026-05-05 19:55:39","changed_gmt":"2026-05-05 19:57:56","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2026-05-15T14:00:00-04:00","event_time_end":"2026-05-15T16:00:00-04:00","event_time_end_last":"2026-05-15T16:00:00-04:00","gmt_time_start":"2026-05-15 18:00:00","gmt_time_end":"2026-05-15 20:00:00","gmt_time_end_last":"2026-05-15 20:00:00","rrule":null,"timezone":"America\/New_York"},"location":"Montgomery Knight Room 317","extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"102851","name":"Phd proposal"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}