水导激光技术中水-光耦合传能规律研究

水-光耦合传输效率是实现水导激光可加工性的前提与效率保证。为了研究水导激光中水-光耦合传能规律, 得到较高的水束中激光功率传输效率和均匀的激光功率密度分布, 采用光线追迹原理及物理光学传播方法, 仿真分析了1064nm激光束聚焦后的光束特性及水-光耦合后水束中激光光斑分布形态, 并对不同水束长度下激光功率传输效率, 以及不同功率、压力和水束长度下激光功率密度分布情况进行了系统的实验检测分析。结果表明, 随着水束长度的减小, 1064nm激光在水束中功率传输效率越高, 在水束长度为20mm时, 激光功率传输效率可达63.6%;激光功率的变化对水束中激光功率密度分布影响最大; 当激光功率不变时, 在水束稳定长度范围内水压的增大有利于水束中激光功率密度均匀化分布, 而耦合水束长度的减小可以提高激光传输效率。研究结果为提高水导激光中能量利用率有一定的指导意义。

Study on energy transmission law of water-laser coupling in water-jet guided laser technology

Water-laser coupling transmission efficiency is the premise and efficiency guarantee of water-jet guided laser machinability. In order to study the law of water-laser coupling energy transmission in water-jet guided laser, and to obtain high laser power transmission efficiency and uniform laser power density distribution in water beam, by using ray tracing theory and physical optics propagation method, the simulation analysis of the focused beam characteristics at 1064nm and the speckle beam pattern after coupling were carried out. And the laser power transmission efficiency under different water beam length, the distribution of laser power density under different power, pressure and water beam length were tested and analyzed systematically. The results show that the power transmission efficiency of 1064nm laser increases with the decrease of the water beam length, and the power transmission efficiency can reach 63.6% when the water beam length is 20mm. The variation of laser power has the greatest influence on the distribution of laser power density in water beam. When the laser power is constant, the increase of water pressure is beneficial to the uniform distribution of laser power density in the stable length of water beam, and the decrease of coupled water beam length can improve laser transmission efficiency. The research results provide some guidance for improving the energy utilization rate of water guided laser.