Investigation on ultrasonic crossjet for laser welding

In laser beam welding,an appropriate crossjet nozzle should be mounted under the welding head in order to protect the optics from the welding spatter and smoke.An ultrasonic crossjet with a non-symmetric Laval cavity is designed based on the aerodynamic theory.Schlieren trial show that a rigid flow with a small divergence is obtained,and no disturbing near the flow can be observed.Welding experiments prove that focusing mirror is well protected when such a crossjet is used.