Research focuses on the study of propulsion systems, with a special strength in the development and application of advanced optical diagnostics. Specific research directions include the study of fundamental turbulence-chemistry interactions, aerospace propulsion devices, internal combustion engines, fuel spray physics and chemistry, and nano-scale energetic materials.

 

Gallery of Flow and Flame Measurements:

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Hyperspectral Tomography

This videos shows the measured temperature distribution at the exhaust plane of an augmentor-equipped J85-GE gas turbine engine at 50 kHz. The measurements were obtained by a technique called Hyperspectral Tomography (HT). This sample video shows the temperature distribution under full afterburner condition and a total of 100 frames were shown in this video, corresponding to a duration of 2 ms.

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Chemiluminescence Tomography

This video shows the three-dimensional (3D) rotational view of a turbulent jet flame (a methane-air premixed flame) stabilized by a V-gutter. The measurements were obtained in 0.2 millisecond with five high-speed cameras via technique called chemiluminescence tomography. The physical measurement volume was 16×16×16 cm3 and the discretization shown here was 64×64×64, resulting in a nominal spatial resolution of 0.25 cm.

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Cone Flame Mie Scattering

This video shows the visualization of a premixed flame using planar Mie scattering from seeded oil droplets. The video was captured with a CCD camera synced with a Nd:YAG, single-pulse, 532 nm laser at 10 Hz. The fuel and oxidizer used here were methane and air, respectively, at an equivalence ratio of 0.9. The bright dots are olive oil droplets (~1μm diameter) entrained in the flow. The boundary between the white dots and the background represents the reaction zone, because the oil droplets evaporate upon entering the reaction zone.

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High Speed Mie Scattering Video

This video visualizes a turbulent jet flow by Mie scattering from water droplet seeded in the flow. The droplets were illuminated by a high speed laser, operating at 5 kHz repetition with 2 microsecond pulse duration. The flow pattern seen in this video was created by a V-shaped bluff body above a jet flow.

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Water Mie Scattering

This video shows the eddies (Kármán vortex street) created by a jet flow behind a V-shaped bluff body. These eddies were visualized by planar Mie scattering from water aerosols seeded in the flow. A 532 nm Nd:YAG laser firing at 10 Hz is collimated to produce a laser sheet, which illuminated the water droplets as seen in this video.

Research Projects

Thermal management of batteries
Thermal Management of Batteries
Hyperspectral Tomography Sensors
Hyperspectral Tomography Sensors
Nd-Yag Laser Setup
Photodissociation Spectroscopy
Simultaneous Vapor
Simultaneous Vapor and Droplet Measurements
Active Combustion Control
Active Combustion Control
Laser Diagnostics Pic
Laser Diagnostics
Flame Disturbed
Nd-YAG Laser Reacting to Candle Flame