SUBJECT: Ph.D. Proposal Presentation
   
BY: Samuel Petter
   
TIME: Tuesday, December 8, 2020, 3:00 p.m.
   
PLACE: https://bluejeans.com/648871920?src=calendarLink, online
   
TITLE: Hydrodynamic Instabilities in Blast Driven Turbulence
   
COMMITTEE: Dr. Devesh Ranjan, Chair (ME)
Dr. Alexander Alexeev (ME)
Dr. Cyrus Aidun (ME)
Dr. Suresh Menon (AE)
Dr. Wenting Sun (AE)
 

SUMMARY


In the core collapse of a supernova, a blast wave is released, and the various layers of the star are violently imparted outward into each other. The hydrodynamic mixing of this astrophysical phenomenon is reproduced in the Blast Wave Facility. The Blast-driven instability, a hydrodynamic instability comprised of both the Richtmyer-Meshkov and the Rayleigh-Taylor instabilities, is the type of instability present in supernova. This attempts to reach dissipative-scaled hydrodynamics, capturing density and velocity fields, resolving the Taylor-microscale to understand the turbulence present in this variable acceleration mixing. Previously, we have shown repeatable Taylor-Sedov blast wave generation, highly repeatable non-diffuse, interface creation, and consistent reproduction of the blast driven instability. Development of the physics has been shown qualitatively at high speed (20 frames per second) using Mie scattering techniques. I want to introduce a new platform of low-speed experiments that will be used to show ensemble statistics of the BDI. Using diagnostics like particle image velocimetry and planar laser induced fluorescence, we make velocity-density field measurements in transient, variable density flows. The primary purpose of this work is to develop an experimental platform capable of collecting velocity-density cross statistics, and tuning the coefficients in the RANS models that are used for predicting flows involving variable density and variable acceleration.