High Mach number jets emanating from young stars show remarkable collimation, low opening angle and resilience against the growth of instabilities, especially the asymmetric ones. In recent laboratory experiments instances of asymmetric three-dimensional low amplitude long waves aligned with the jet axis were observed by Belan et al (2013 Astron. Astrophys. 554 A99). To explore the collimation, spreading, and asymmetric stability properties of hypersonic jets we carried out laboratory experiments and numerical simulations in two and three spatial dimensions. We find that laboratory hydrodynamic jets with high Mach numbers remain collimated, for hundreds of jet radii in length and maintain low opening angles. These findings are confirmed by 3D numerical simulations carried out after time-dependent, asymmetric perturbations are applied at the jet inlet. Both experimental and perturbed simulated jets show non-axial modes with long wavelengths, whose growth does not disrupt the jet in the domain considered.

Hypersonic jets in astrophysical conditions: focus on spreading and asymmetric stability properties

MIGNONE, ANDREA;MASSAGLIA, Silvano
2014-01-01

Abstract

High Mach number jets emanating from young stars show remarkable collimation, low opening angle and resilience against the growth of instabilities, especially the asymmetric ones. In recent laboratory experiments instances of asymmetric three-dimensional low amplitude long waves aligned with the jet axis were observed by Belan et al (2013 Astron. Astrophys. 554 A99). To explore the collimation, spreading, and asymmetric stability properties of hypersonic jets we carried out laboratory experiments and numerical simulations in two and three spatial dimensions. We find that laboratory hydrodynamic jets with high Mach numbers remain collimated, for hundreds of jet radii in length and maintain low opening angles. These findings are confirmed by 3D numerical simulations carried out after time-dependent, asymmetric perturbations are applied at the jet inlet. Both experimental and perturbed simulated jets show non-axial modes with long wavelengths, whose growth does not disrupt the jet in the domain considered.
16
085002
085014
http://iopscience.iop.org/1367-2630/16/8/085002/pdf/1367-2630_16_8_085002.pdf
M Belan;D Tordella;S De Ponte;A Mignone;S Massaglia
File in questo prodotto:
File Dimensione Formato  
belan14_NJP_16_8_085002.pdf

Accesso aperto

Tipo di file: PDF EDITORIALE
Dimensione 1.03 MB
Formato Adobe PDF
1.03 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/154327
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 5
  • ???jsp.display-item.citation.isi??? 3
social impact