skip to main content

DOE PAGESDOE PAGES

Title: Observation of single-mode, Kelvin-Helmholtz instability in a supersonic flow

This manuscript reports the first observations of the Kelvin-Helmholtz instability evolving from well-characterized seed perturbations in a steady, supersonic flow. The Kelvin-Helmholtz instability occurs when two fluids move parallel to one another at different velocities, and contributes to an intermixing of fluids and transition to turbulence. It is ubiquitous in nature and engineering, including terrestrial systems such as cloud formations, astrophysical systems such as supernovae, and laboratory systems such as fusion experiments. In a supersonic flow, the growth rate of the instability is inhibited due to effects of compressibility. These effects are still not fully understood, and hold the motivation for the current work. The data presented here were obtained by developing a novel experimental platform capable of sustaining a steady shockwave over a precision-machined interface for unprecedented durations. The chosen interface was a well-characterized, single-mode sine wave, allowing us to document the evolution of individual vortices at high resolution. Understanding the behavior of individual vortices is the first of two fundamental steps towards developing a comprehensive model for the Kelvin-Helmholtz instability in a compressible flow. The results of this experiment were well reproduced with 2D hydrodynamic simulations. The platform has been extended to additional experiments, which study the evolutionmore » of different hydrodynamic instabilities in steady, supersonic flows.« less
Authors:
 [1] ;  [2] ;  [3] ;  [1] ;  [1] ;  [1] ;  [4] ;  [1] ;  [1]
  1. Univ. of Michigan, Ann Arbor, MI (United States)
  2. Univ. of Michigan, Ann Arbor, MI (United States); Nuclear Research Center - Negev, Beer Sheva (Israel)
  3. Nuclear Research Center - Negev, Beer Sheva (Israel); Ben Gurion Univ. of the Negev, Beer Sheva (Israel)
  4. Univ. of Michigan, Ann Arbor, MI (United States); Nuclear Research Center - Negev, Beer Sheva (Israel); Ben Gurion Univ. of the Negev, Beer Sheva (Israel)
Publication Date:
OSTI Identifier:
1336026
Grant/Contract Number:
NA0002032
Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 115; Journal Issue: 14; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Research Org:
Univ. of Michigan, Ann Arbor, MI (United States)
Sponsoring Org:
USDOE; National Laser User Facility Program (NLUF)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY supersonic; compressible; Kelvin-Helmholtz instability; hydrodynamic instabilities