Numerical and Experimental Study of Shielding Gas Orientation Effects on Particle Stream Concentration Mode in Coaxial Laser Aided Material Deposition Process

2004 ◽  
Author(s):  
Heng Pan ◽  
Yogesh D. Thakar ◽  
Frank Liou
Keyword(s):  
Experimental Study ◽  
Gas Flow ◽  
Velocity Ratio ◽  
Deposition Process ◽  
Numerical Approach ◽  
Shielding Gas ◽  
Two Phase ◽  
Powder Concentration ◽  
Turbulence Flow ◽  
Material Deposition

Laser aided deposition quality largely depends on the powder stream structure below the nozzle. Modeling of the powder concentration distribution rarely relies on the numerical approach partially due to the complex phenomenon involved in the two-phase turbulence flow. In this paper, a numerical model is introduced to predict the particle-gas flow precisely and economically in order to meet the practical requirement for coaxial nozzle design optimizations. This model is able to quantitatively predict the powder stream concentration mode under different outer shielding gas directions and inner/outer gas velocity ratio. The numerical simulation results are compared with the experimental study using prototyped coaxial nozzles. The results are found to match. This study shows that the particle concentration mode is influenced significantly by the outer gas direction and gas flow settings.

The Investigation of Gravity-Driven Metal Powder Flow in Coaxial Nozzle for Laser-Aided Direct Metal Deposition Process

2005 ◽  
Vol 128 (2) ◽  
pp. 541-553 ◽  
Author(s):  
Heng Pan ◽  
Todd Sparks ◽  
Yogesh D. Thakar ◽  
Frank Liou
Keyword(s):  
Gas Flow ◽  
Particle Concentration ◽  
Metal Deposition ◽  
Direct Metal Deposition ◽  
Powder Flow ◽  
Shielding Gas ◽  
Two Phase ◽  
Coaxial Nozzle ◽  
Gravity Driven ◽  
Nozzle Geometries

The quality and efficiency of laser-aided direct metal deposition largely depends on the powder stream structure below the nozzle. Numerical modeling of the powder concentration distribution is complex due to the complex phenomena involved in the two-phase turbulence flow. In this paper, the gravity-driven powder flow is studied along with powder properties, nozzle geometries, and shielding gas settings. A 3-D numerical model is introduced to quantitatively predict the powder stream concentration variation in order to facilitate coaxial nozzle design optimizations. Effects of outer shielding gas directions, inner/outer shielding gas flow rate, powder passage directions, and opening width on the structure of the powder stream are systematically studied. An experimental setup is designed to quantitatively measure the particle concentration directly for this process. The numerical simulation results are compared with the experimental data using prototyped coaxial nozzles. The results are found to match and then validate the simulation. This study shows that the particle concentration mode is influenced significantly by nozzle geometries and gas settings.

Parallel Numerical Prediction of Pulverized Coal Particle Flow in Bifurcator-Type Flow Splitters

2003 ◽  
Vol 125 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Th. Frank ◽  
H. Schneider ◽  
K. Bernert ◽  
K. Pachler
Keyword(s):  
Numerical Simulation ◽  
Gas Flow ◽  
Stokes Equations ◽  
Decomposition Methods ◽  
Numerical Approach ◽  
Navier Stokes ◽  
Two Phase ◽  
Navier Stokes Equations ◽  
Numerical Effort ◽  
Tracking Model

This paper deals with the numerical simulation of two-phase flows based on the solution of the Navier-Stokes equations with a k−ε turbulence model for the gas phase and a particle tracking model of the disperse phase fulfilling the framework of the Eulerian-Lagrangian (PSI-cell) approach. The numerical procedures for the two phases are based on multigrid and domain decomposition methods applied to a block-structured grid. Due to the enormous numerical effort of such flow simulations the entire solving procedure has been parallelized for computers of MIMD architecture. The paper gives a short description of the applied and developed numerical methods. Furthermore the numerical simulation of a particle laden gas flow through a flow splitter from the area of power engineering is presented as an example for a real world application of the numerical approach.

scholarly journals Numerical approach for the estimation of the deposited material on the laser material deposition process

Procedia CIRP ◽  
2018 ◽  
Vol 74 ◽  
pp. 785-789
Author(s):  
A. Lamikiz ◽  
J.I. Arrizubieta ◽  
E. Ukar ◽  
S. Martínez ◽  
J.E. Ruiz ◽  
...  
Keyword(s):  
Deposition Process ◽  
Numerical Approach ◽  
Laser Material ◽  
Material Deposition

Experimental Study of Particle Size, Sound Velocity, and Resonance Phenomena in a Two-Phase Foam Flow

2001 ◽  
Vol 32 (4-6) ◽  
pp. 5
Author(s):  
A. P. Sevast'yanov ◽  
I. V. An ◽  
S. I. Vainshtein ◽  
Yu. A. Sevast'yanov ◽  
A. V. Sidnev ◽  
...  
Keyword(s):  
Experimental Study ◽  
Particle Size ◽  
Sound Velocity ◽  
Two Phase ◽  
Foam Flow ◽  
Resonance Phenomena
Sign in / Sign up

Export Citation Format

Share Document