Simulation and optimization of gas flow behavior in the chamber for laser processing

In order to make the weld seams immune to the hydrogen, oxygen and nitrogen uptake, laser processing of the alloys possessed active chemical property was always performed in the chamber. The optimization of the gas flow behavior in the chamber was of vital importance to eliminate the heat and smoke produced during the laser processing. In the present study, the influences of number and angle of air knives, inlet flow rate on the gas flow behavior in the chamber were investigated respectively. The results indicate that two air knives were necessary to make the gas flow over the workpiece and prevent the backflow of external gas. The optimal gas flow behavior could be obtained while the angle of the adjustable air knife and gas flow rate were 30°-45° and 60-120 L/min respectively.