碟片式激光烧蚀微推力器靶盘利用率优化

Optimization of target plate utilization of disk-type laser ablation microthrusters

碟片式激光烧蚀推力器的总冲与靶盘上烧蚀点数量线性相关,提高靶盘利用率有利于在有限的靶面上得到更多的烧蚀点。为了优化靶盘利用率,文中首先对激光烧蚀微推力器进行了结构设计和分析,对靶盘上的烧蚀点分布问题进行了理论建模,提出了串珠法和套圈法两种分析方法,分别设计了圆圈路径、螺旋路径和六角密排三种实际烧蚀点分布方式。通过计算,分析比较了三种分布方式下,靶盘尺寸和烧蚀点尺寸对靶盘利用率的影响规律。结果表明,六角密排的靶盘利用率理论最高可达90.64%,圆圈路径和螺旋路径的靶盘利用率理论最高可达78.54%;靶盘利用率受到靶盘尺寸和烧蚀点尺寸的影响,靶盘尺寸较小时,圆圈路径的靶盘利用率相对较大,靶盘尺寸较大时,六角密排的靶盘利用率较大;三种分布方式各有特点,在应用上各有侧重。该研究为充分利用碟片式激光烧蚀推力器的靶盘提供了理论指导和设计参考,对推力器的工程化设计有一定借鉴意义。

The total impulse of a disc-type laser ablation thruster is linearly related to the number of ablation points on the target disk,and improving the utilization rate of the target disk is beneficial to obtain more ablation points on the limited target disk surface.In this paper,to optimize the utilization rate of the target disk,the structure of the laser ablation microthrusters was designed and analyzed.The distribution of the ablation point on the target disk was theoretically modelled,two analytical principles,namely,the bead principle and the collar principle,were proposed,and three actual ablation point distribution methods,namely,the circle path,the spiral path and the hexagonal pack,were designed.Through calculation,the influence law on the utilization rate of the target disk by the size of the target disk and the size of the ablation point under the three distribution methods was analyzed and compared.The results show that the target disk utilization rate of the hexagonal pack can reach up to90.64%,and the target disk utilization rate theory of the circle path and spiral path can reach up to 78.54%.The target disk utilization rate is affected by the size of the target disk and the size of the ablation point.When the size of the target disk is small,the target disk utilization rate of the circle path is relatively large.When the size of the target is large,the target disk utilization rate of the hexagonal pack is relatively large.Each of the three distribution methods has its own characteristics and has its own emphasis on application.The research provides theoretical guidance and a design reference for the full utilization of the target disk of the disc-type laser ablation thruster,and has some reference significance to the engineering design of the thruster.