【摘要】 本试验运用双反射式平等光纹影仪对激光焊接用双层喷嘴冷态时的气流流态进行了系统的观测、研究,并结合气体动力学原理对气流的流态进行了分析。试验结果表明:对于实际激光焊接中所使用的喷嘴,单层冷态自由射流时,为获得较好的层流长度及挺度,气流的雷诺数必须控制在400～700的范围内;双层冷态自由射流时,为使内外层气流间的影响最小及双层气流的综合性能达到最佳,必须使内、外层气流的雷诺数相接近。更多还原

【Abstract】 The jet’s form of double-layer nozzle used in laser welding was systemically researched in the experiment by a twi-reflector schlieren instrument, and analyzed by aerodynamics. The results showed that, for the nozzles actually used in laser welding, to obtain the satisfying length of laminar flow and velocity of flow, the Reynolds-number of single-layer nozzle’s free-jet, which is not for welding state, should range from 400 to 700; when it concerned the double-layer nozzle, the Reynolds-number of inner and outer layers should be close to each other in order to get a laminar flow with better practicability.更多还原