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

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 to 90.64%, 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.