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:
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.
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.
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.
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.
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.