Laser gas assisted melting and thermal efficiency analysis


Boran K.

LASERS IN ENGINEERING, vol.18, pp.187-202, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 18
  • Publication Date: 2008
  • Journal Name: LASERS IN ENGINEERING
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.187-202
  • Gazi University Affiliated: Yes

Abstract

In the present study, laser gas assisted melting of a solid surface is modelled using a scale analysis. The melt surface speed in the direction of the assisting gas flow and melt depth are formulated in terms of the laser output power and the rate of the assisting gas at the edge of the boundary layer. It was found that increasing the laser power level enhances the thickness of the liquid layer whereas the high speed of the assisting gas decreases the thickness of the liquid layer due to large magnitude of the dragging force developed at the assisting gas-liquid interface (melt surface). Increasing the speed of the assisting gas at the edge of the boundary layer increases the speed of the liquid layer on the melted surface. The thermal efficiency is improved significantly as the laser power levels increase; in this case, the rate of convection and conduction heat transfer from the melt layer is less than that compared with the laser power available at the melt surface.