Modelling of turbulent molten pool convection in laser welding of a copper–nickel dissimilar couple

The effects of turbulence on momentum, heat, and mass transfer during laser welding of a copper–nickel dissimilar couple are studied by carrying out three-dimensional unsteady Reynolds Averaged Navier Stokes (RANS) simulations. The turbulent transport is modelled by a suitably modified high Reynolds number k–e model. The solid–liquid phase change is accounted for by a modified enthalpy porosity technique. In order to demonstrate the effects of turbulence, two sets of simulations are carried out for the same set of processing parameters: one with the turbulence model, and the other without activating the turbulence model. The enhanced diffusive transport associated with turbulence is shown to decrease the maximum values of temperature, velocity magnitude, and copper mass fraction in the molten pool. The effects of turbulence are found to be most prominent on the species transport in the molten pool. The composition distribution in turbulent simulation is found to be more uniform than that obtained in the simulation without turbulent transport. The nickel composition distribution predictions, as obtained from the present turbulence model based simulations, are also found to be in good agreement with the corresponding experimental results.

[1]  R. Guthrie,et al.  Numerical study of coupled turbulent flow and solidification for steel slab casters , 1995 .

[2]  B. A. Kader.  Temperature and concentration profiles in fully turbulent boundary layers , 1981 .

[3]  Pradip Dutta,et al.  Modelling of turbulent transport in arc welding pools , 2003 .

[4]  S. Patankar.  Numerical Heat Transfer and Fluid Flow , 2018, Lecture Notes in Mechanical Engineering.

[5]  Pradip Dutta,et al.  Modelling of transport phenomena in laser welding of dissimilar metals , 2001 .

[6]  A. Bejan.  Convection Heat Transfer , 1984 .

[7]  C. J. Smithells,et al.  Smithells metals reference book , 1949 .

[8]  PengSheng Wei,et al.  Mass, Momentum, and Energy Transport in a Molten Pool When Welding Dissimilar Metals , 1999 .

[9]  S. Chakraborty,et al.  Influences of Sign of Surface Tension Coefficient on Turbulent Weld Pool Convection in a Gas Tungsten Arc Welding (GTAW) Process: A Comparative Study , 2005 .

[10]  A. B. Strong,et al.  The predicted influence of turbulence in stationary gas tungsten arc welds , 1996 .

[11]  T. DebRoy,et al.  Role of thermophysical properties in weld pool modeling , 1992 .

[12]  S. Chakraborty,et al.  MODELING OF TURBULENT TRANSPORT IN LASER SURFACE ALLOYING , 2004 .

[13]  S. Chakraborty,et al.  THREE-DIMENSIONAL MODELING OF TURBULENT WELD POOL CONVECTION IN GTAW PROCESSES , 2004 .

[14]  J. S. Ku,et al.  Fusion Zone Shapes in Electron-Beam Welding Dissimilar Metals , 2000 .

[15]  S. Chakraborty,et al.  Scaling analysis of momentum and heat transport in gas tungsten arc weld pools , 2002 .

[16]  J. Szekely,et al.  The Possible Role of Turbulence in GTA Weld Pool Behavior , 1994 .

[17]  S. Chakraborty,et al.  A scaling analysis of turbulent transport in laser surface alloying process , 2004 .

[18]  Yogendra Joshi,et al.  Determination of gas tungsten arc welding efficiencies , 1994 .

[19]  Mamoru Ishii,et al.  Two-fluid model and hydrodynamic constitutive relations , 1984 .

[20]  Vaughan R Voller,et al.  ENTHALPY-POROSITY TECHNIQUE FOR MODELING CONVECTION-DIFFUSION PHASE CHANGE: APPLICATION TO THE MELTING OF A PURE METAL , 1988 .

[21]  Y. Joshi,et al.  Nonaxisymmetric convection in stationary gas tungsten arc weld pools , 1997 .

[22]  M. B. Carver.  Numerical computation of phase separation in two fluid flow , 1984 .

[23]  Wei Shyy,et al.  Modeling of turbulent transport and solidification during continuous ingot casting , 1992 .

[24]  D. R. Atthey.  A mathematical model for fluid flow in a weld pool at high currents , 1980, Journal of Fluid Mechanics.

[25]  P. Wei,et al.  Unsteady marangoni flow in a molten pool when welding dissimilar metals , 2000 .

[26]  P. Dutta,et al.  Computational modeling of laser welding of Cu-Ni dissimilar couple , 2004 .