RESEARCH PROJECTS
Transient plasma ignition (TPI)

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Exploring fundamental aspects of advanced ignition systems to enable clean and efficient engine combustion strategies, with a particular focus on transient plasma ignition (TPI) using low-temperature plasma (LTP)
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Investigated low-temperature transient plasma characteristics using laser measurement techniques such as 2-photon absorption laser-induced fluorescence of atomic oxygen (O-TALIF), Thomson and Raman scattering, Schlieren, ozone absorption and filtered imaging of various radicals

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Identified dominant chemical pathways for plasma ignition of gaseous and liquid fuels
Ozone added spark assisted compression ignition (SACI)
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Ozone—a powerful oxidizing chemical agent generated through onboard coronal discharges in intake air—can be used to significantly alter gasoline reactivity, and thereby enable stable auto-ignition with less initial charge heating
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Ozone addition stabilized combustion relative to similar conditions without ozone by increasing end gas reactivity
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However, the impact of ozone addition decreased with increased engine speed due to shorter residence times available for auto-ignition
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Ozone addition can facilitate mixed-mode (SI, ACI, SACI, etc.) combustion


Supersonic reacting jet ignition for ultra-lean clean combustion
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Designed and performed experiments to study supersonic hot jet ignition of premixed CH4/air and H2/air
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Hypothesized jet ignition mechanisms (an alternative for spark-ignition engines) for environment-friendly future combustion techniques for automotive and gas turbine applications
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Characterized turbulent flame propagation using high-speed Schlieren, OH* chemiluminescence, Particle Image Velocimetry (PIV), and Infrared (IR) imaging
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Proposed a Schlieren based novel velocity measurement technique, Schlieren Image Velocimetry (SIV)
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Investigated thermo-acoustic combustion instability for ultra-lean limit in constant volume combustor
Advanced combustion modeling with detailed turbulence-chemistry interaction
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Evaluated emission characteristics (NOx, SO2) of lean CH4/air and H2/air in dual chamber combustor
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Numerically investigated coupling between chemistry and turbulence of supersonic reacting jet in inert medium using detailed chemistry for hydrogen and natural gas
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Modeled reacting supersonic jet using Unsteady Reynolds Averaged Navier Stokes (URANS) in ANSYS Fluent, ICEM CFD
High-temperature ignition delay measurements of biodiesel blend

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Investigated ignition delay of Methyl Ester-based biofuel blends in High Pressure (20-60 atm) and High Temperature (1000-1500 K) Shock Tube (HPHT-ST)
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Identified chemical mechanisms for biofuel blends based on shock tube data
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Constructed chemical mechanisms for biofuel blends using reaction path analysis
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Developed experiments to study CH4/air flame propagation through narrow channel
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Examined flame propagation, stabilization, and flame extinction limits to develop combustion based micro-power generation systems such as micro aerial vehicles, microsatellite thrusters, and microchemical reactors
Flame propagation in narrow convergent-divergent channel
Ignition by chemically reacting impinging jet and multiple jets
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Investigated ignition physics by chemically reacting impinging jets to achieve superior control of ignition location and ignition delay
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Identified the effect of jet interactions during reacting jet ignition process
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Proposed guidelines for future pre-chamber designs for cleaner and efficient combustion
Bluff-body stabilized turbulent flames in a prototype jet-engine afterburner
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Researched blowoff dynamics of bluff-body stabilized V-shaped propane/air flames under fuel stratification and self-excited oscillations
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Quantified flame behavior near blowoff using simultaneous PIV-PLIF and high-speed CH* imaging
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Performed phase-locked PIV, CH* chemiluminescence, OH-PLIF, and Rayleigh scattering to investigate forced blowoff mechanisms in lab scale burner
Scalar mixing in the field of closely interacting vortex pairs and couples
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Designed and built experiment to study mixing statistics of interacting laminar vortices
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Assessed scalar distribution in vortical flow using Planar Laser Induced Fluorescence (PLIF) of acetone
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Studied flame-vortex interactions