Sign on

SAO/NASA ADS Astronomy Abstract Service


· Find Similar Abstracts (with default settings below)
· Full Refereed Journal Article (PDF/Postscript)
· Full Refereed Scanned Article (GIF)
· References in the article
· Citations to the Article (56) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (3)
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
The stability and collimation of three-dimensional jets
Authors:
Hardee, Philip E.; Clarke, David A.; Howell, D. Andrew
Affiliation:
AA(University of Alabama, Tuscaloosa, AL), AB(University of Alabama, Tuscaloosa, AL), AC(University of Alabama, Tuscaloosa, AL)
Publication:
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 441, no. 2, p. 644-664 (ApJ Homepage)
Publication Date:
03/1995
Category:
Astrophysics
Origin:
STI
NASA/STI Keywords:
Collimation, Hydrodynamics, Interstellar Matter, Jet Flow, Shock Waves, Stability, Three Dimensional Models, Computerized Simulation, Temporal Resolution, Velocity Distribution
DOI:
10.1086/175389
Bibliographic Code:
1995ApJ...441..644H

Abstract

A three-dimensional hydrodynamical simulation of a Mach 5 cylindrical jet established in equilibrium with a surrounding uniform atmosphere of 10 times the jet density has been performed and is compared with a previous Mach 3 simulation. The grid resolution used is significantly higher than was used in the previous simulation of a Mach 3 equilibrium jet. The higher resolution has not significantly changed the development of large-scale structures such as the helical twisting of the jet, the elliptical distortion and bifurcation of the jet, or the triangular distortion and trifurcation of the jet seen in the lower resolution simulation. These structures arise from the Kelvin-Hemholtz unstable surface modes predicted by the linear theory, and the elliptical mode appears coupled to the precessionally driven helical mode. Newly discovered is a short-wavelength, relatively large-amplitude transverse velocity oscillation on the jet axis. The effect of the unstable body modes on jet structure is analyzed for the first time, and a helical internal body mode is revealed to be responsible for the observed short-wavelength velocity oscillation on the jet axis. This body mode helically twists the inner 20%-25% of the jet, and the transverse velocity oscillation occurs at the fastest spatially growing wavelength predicted by the theory. While the higher resolution of the new simulation has allowed the development of structures on smaller scales and reveals more detail, large-scale surface distortion and accompanying surface filamentation still appear to dominate jet dynamics, and decollimation occurs as the helically distorted jet bifurcates or trifurcates. This newer simulation suggests that mass entrainment, and significant heating and dissipation, occur as the jet breaks up into multiple streams, and qualitative comparison between the two simulations suggests that more shock heating and decollimation occur in the Mach 5 simulation.

Printing Options

Print whole paper
Print Page(s) through

Return 600 dpi PDF to Acrobat/Browser. Different resolutions (200 or 600 dpi), formats (Postscript, PDF, etc), page sizes (US Letter, European A4, etc), and compression (gzip,compress,none) can be set through the Printing Preferences



More Article Retrieval Options

HELP for Article Retrieval


Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)


Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints