Modeling and analysis of the visualized gas-assisted laser cutting flow from both conical and supersonic nozzles

0525097 - ÚPT 2021 RIV GB eng J - Journal Article
Darwish, M. - Mrňa, Libor - Orazi, L. - Reggiani, B.
Modeling and analysis of the visualized gas-assisted laser cutting flow from both conical and supersonic nozzles.
International Journal of Advanced Manufacturing Technology. Roč. 106, č. 9-10 (2020), s. 4635-4644. ISSN 0268-3768. E-ISSN 1433-3015
Institutional support: RVO:68081731
Keywords : gas-assisted laser cutting * openFOAM * schlieren visualization * supersonic nozzles * stand-off distance * cut kerf
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 3.226, year: 2020
Method of publishing: Limited access
https://link.springer.com/article/10.1007/s00170-019-04915-4

A coaxial high-pressure gas jet is normally used to assist and enhance laser cutting quality and capability. However, the gas nozzles are mostly of conical type causing the deterioration of the dynamic characteristics of the exit jet. In this research, the effect of both nozzle type and nozzle dimensions on the uniformity and behavior of the exit jet has been investigated. A total of three different supersonic nozzles have been designed in accordance to gas dynamics theory and manufactured using wire electrical discharge machining (WEDM). The exit jet patterns from these supersonic nozzles and a reference conical nozzle have been numerically modeled and compared with the experimental observations made through Schlieren visualization. The experimental results are found to match and hence validate the simulations. It is concluded that the exit jet from the supersonic nozzle is marked by uniformity, better dynamic characteristics, and longer effective exit jet length compared with conical nozzle.
Permanent Link: http://hdl.handle.net/11104/0309310