Numerical investigation of hydrodynamics behaviour of melt layer during laser cutting of steel

Autor:	Toufik Tamsaout, El-Hachemi Amara
Rok vydání:	2014
Předmět:	Jet (fluid) Materials science Finite volume method Laser cutting business.industry Thermodynamics Laminar flow General Chemistry Mechanics Computational fluid dynamics Instability Fluent General Materials Science business Melt flow index
Zdroj:	Applied Physics A. 117:383-388
ISSN:	1432-0630 0947-8396
DOI:	10.1007/s00339-014-8497-x
Popis:	Understanding of the melt layer hydrodynamic behaviour during laser-cutting process under gas jet assistance is of high importance for cut quality control. In the present work, a numerical model is developed to calculate the three-dimensional behaviour of the melt flow on the kerf front, while an inert gas jet interacts with the melt film. Fluent CFD code is used to solve the governing hydrodynamic equations by finite volume method. The results show that the melt flow on the kerf front reveals a strong instability, which depends on the cutting speed and on the gas jet velocity. Global flow behaviour (gas and molten metal flows) computed using a laminar model, reveals oscillations of the gas–metal liquid interface, which is assimilated to Kelvin–Helmholtz instability. The origin of this instability is discussed in terms of instabilities in thermal dynamics and hydrodynamics. Instability in thermal dynamics is related to the localized melting, while the instability in hydrodynamics is governed by forces balance between gas and resistant surface tension.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::1cf1bb7cdba4b6112060c0e8a288250d https://doi.org/10.1007/s00339-014-8497-x Zobrazit plný text záznamu Plný text ve formátu PDF