Mechanical Engineering ETDs


Joseph Conroy

Publication Date



We present an experimental study that visualizes the effects of a planar shock front passing through air (or SF6) randomly seeded with glycol droplets or smoke particles. It was observed, using a high-speed multiple-CCD (charge coupled device) camera, that an instability occurs as the shock wave bypasses the slow-moving column of gas. This produced evident perturbation at the interface. The flow morphology of the gas column consists of a pair of counter-rotating vortices that develops downstream from the initial conditions as well as some secondary instabilities (in certain cases). Some images also show a trailing tail due to larger particles lagging behind the flow. The data and images obtained in the experiments were gathered using a tilt-able shock tube made of solid stock aluminum, two green-light lasers, and other high-speed diagnostics. Our experimental data cover a range of Mach numbers from 1.22 to 2.02. Each experimental run was performed with the shock tube in the horizontal position, causing only 2-D visualization effects.


Shear flow, Vortex-motion, Shock waves, Stokes equations, Shock tubes.

Degree Name

Mechanical Engineering

Level of Degree


Department Name

Mechanical Engineering

First Advisor

Vorobieff, Peter

First Committee Member (Chair)

Truman, Randall

Second Committee Member

Nygren, Richard

Document Type