Microscopic high-speed liquid-metal jets in vacuum

• Published in: Experiments in fluids 2005-11, Vol.39 (5), p.799-804
• Main Authors: OTENDAL, M, HEMBERG, O, TUOHIMAA, T. T, HERTZ, H. M
• Format: Article
• Language: English
• Subjects: brightness; electron-impact; Exact sciences and technology; Fluid dynamics; Fundamental areas of phenomenology (including applications); Fysik; High speed; Instability; Instrumentation for fluid dynamics; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Jets; liquid-metal jet; NATURAL SCIENCES; NATURVETENSKAP; Nozzle design; Physics; Stability; Tin; Turbulent flows, convection, and heat transfer; X- and γ-ray instruments and techniques; X- and γ-ray sources, mirrors, gratings and detectors; X-ray source; X-ray sources
• ISSN: 0723-4864; 1432-1114; 1432-1114
• DOI: 10.1007/s00348-005-0013-9

The operation of microscopic high-speed liquid-metal jets in vacuum has been investigated. We show that such jets may be produced with good stability and collimation at higher speeds than previously demonstrated, provided that the nozzle design is appropriate and that cavitation-induced instabilities are avoided. The experiments with a medium-speed tin jet (u = 60 m/s, Re=1.8x10 super(4), Z=2.9x10 super(-3)) showed that it operated without any signs of instabilities, whereas the stability of high-speed tin jets (d=30 mu m, u=500 m/s, Re=5.6x10 super(4), Z=4.7x10 super(-3)) has been investigated via dynamic similarity using a water jet. Such a 500-m/s tin jet is required as the anode for high-brightness operation of a novel electron-impact X-ray source.