【摘要】 液体介质的循环流动为消除激光系统的热效应提供了有效途径,对改善激光系统的光束质量具有重要意义。根据液体介质的流场特性,结合Fluent6.53软件模拟计算,分析了抽运区介质流速、湍流强度与附面层厚度、温度扰动的关系及对激光热畸变的影响。增大抽运区介质流速能有效减小热畸变和附面层厚度;在给定抽运条件下,采用光阑限孔的方法进一步减小热畸变,流速为20 m/s时的光程差(OPD)最大差值由10个波长下降到5个波长。更多还原

【Abstract】 Circulation system of liquid laser medium provides an effective method of eliminating thermal effect and improving laser beam quality.Based on turbulent flow field characteristic of this laser medium and numerical simulation using software Fluent6.53,the relationship between flow velocity,turbulent intensity,boundary layer thickness and temperature gradient has been investigated,which affects on thermally induced distortion.Increasing velocity of laser medium in the cell would reduce thermally induced distortion and boundary layer thickness.Setting proper aperture under current conditions can also further reduce the distortion.The maximum optical path difference decreases from 10 wavelengths to 5 wavelengths at the flow velocity of 20 m/s by setting aperture.更多还原