Determination of plasma velocity from light fluctuations in a cutting torch

Journal Article · Tue Sep 01 00:00:00 EDT 2009 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3213377· OSTI ID:21361800

Prevosto, L; Mancinelli, B ^[1]; Kelly, H ^[2]

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1. Departamento Ing. Electromecanica, Grupo de Descargas Electricas, Universidad Tecnologica Nacional, Regional Venado Tuerto, Las Heras 644, Venado Tuerto 2600, Pcia. Santa Fe (Argentina)
2. Departamento de Fisica, Instituto de Fisica del Plasma (CONICET), Facultad de Ciencias Exactas y Naturales (UBA), Ciudad Universitaria Pab. I, 1428 Buenos Aires (Argentina)

Measurements of plasma velocities in a 30 A high energy density cutting torch are reported. The velocity diagnostic is based on the analysis of the light fluctuations emitted by the arc which are assumed to propagate with the flow velocity. These light fluctuations originate from plasma temperature and plasma density fluctuations mainly due to hydrodynamic instabilities. Fast photodiodes are employed as the light sensors. The arc core velocity was obtained from spectrally filtered light fluctuations measurements using a band-pass filter to detect light emission fluctuations emitted only from the arc axis. Maximum plasma jet velocities of 5000 m s{sup -1} close to the nozzle exit and about 2000 m s{sup -1} close to the anode were found. The obtained velocity values are in good agreement with those values predicted by a numerical code for a similar torch to that employed in this work.

• OSTI ID: 21361800
• Journal Information: Journal of Applied Physics, Vol. 106, Issue 5; Other Information: DOI: 10.1063/1.3213377; (c) 2009 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANODES
ELECTRON TEMPERATURE
ENERGY DENSITY
HYDRODYNAMICS
ION TEMPERATURE
PHOTODIODES
PLASMA
PLASMA DENSITY
PLASMA INSTABILITY
PLASMA JETS
SENSORS
ELECTRODES
FLUID MECHANICS
INSTABILITY
MECHANICS
SEMICONDUCTOR DEVICES
SEMICONDUCTOR DIODES