Dissertation Defense Schedule
Academic Excellence
Sharing original dissertation research is a principle to which the University of Delaware is deeply committed. It is the single most important assignment our graduate students undertake and upon completion is met with great pride.
We invite you to celebrate this milestone by attending their dissertation defense. Please review the upcoming dissertation defense schedule below and join us!
PROGRAM | Mechanical Engineering
Multi-mode Instabilities Arising in Hypersonic Flow Conditions for Aerospace Applications
By: Tony Liang Chair: Ajay Prasad
ABSTRACT
Research in hypersonic aerodynamics is important in understanding the practicality of sustained high-speed flight and the design parameters of such vehicles. Hypersonic boundary layer transition is dominated by the presence of various disturbance (Mack) modes present within the boundary layer which undergo modal growth and eventually transitions the flow to turbulence.
The aim of this research is to perform an analytical study utilizing computational fluid dynamics (CFD) coupled with stability analysis employing linear stability theory (LST) and parabolized stability equations (PSE) to help understand the dynamics of Mack modes and their nonlinear interactions. One question to be studied is the source of energy driving the 1st and 2nd mode instabilities. A characterization of the energetics of the 1st and 2nd modes was performed at various flow conditions to further understand physical mechanisms governing the modal growth pathway to transition, and was shown that the traditional 1st mode definition is incomplete. A design study into a geometry conducive to 1st and 2nd mode interactions was performed and investigated. With such a geometry, the dynamics between a 1st mode dominated boundary layer with an existing 2nd mode. Finally, with understanding of the thermoacoustic interpretation of the 2nd mode, an impedance boundary condition is applied to a canonical conical geometry in an attempt to analyze its effect on certain unstable waves within the boundary layer. Understanding these dynamics of these modes and their interactions within the boundary layer can bridge the knowledge gaps in the fundamental causes of heat transfer, friction drag, lift and other properties which become critically important in hypersonic flight.
The Process
Step-by-Step
Visit our “Step-by-Step Graduation Guide” to take you through the graduation process.From formatting your Dissertation to Doctoral Hooding procedures.
Dissertation Manual
Wondering how to set up the format for your paper. Refer to the “UD Thesis/Dissertation Manual” for formatting requirements and more.
Defense Submission Form
This form must be completed two weeks in advance of a dissertation defense to meet the University of Delaware Graduate and Professional Education’s requirements.
