Dynamic characteristics of gas jets from subsonic and supersonic nozzles for high pressure gas laser cutting

Hau Chung Man, J. Duan, Tai Man Yue

Research output: Journal article publicationJournal articleAcademic researchpeer-review

47 Citations (Scopus)


During laser cutting of stainless steels, titanium and aluminum alloys, a coaxial and high pressure inert gas jet is used to improve the cut edge quality. The process normally consumes a large amount of inert gas and has a poor tolerance to variation in process parameters. This is solely because the gas nozzles are mostly of the conical and convergent type in which the gas jets are subsonic. Based on two dimensional steady state gas dynamic theory, computer simulation and shadowgraphic techniques, the gas jet patterns from conical nozzles and the newly designed supersonic nozzles are analyzed. The distribution of pressure, momentum, gas density and existence of shock waves are predicted and mapped. Based on these characteristics, the effect of the gas jets upon the cut quality is explained. It is concluded that a supersonic gas jet offers the best flow characteristics for high pressure laser cutting.
Original languageEnglish
Pages (from-to)497-509
Number of pages13
JournalOptics and Laser Technology
Issue number8
Publication statusPublished - 1 Jan 1998

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Electrical and Electronic Engineering

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