Abstract
This paper proposes a method to determine the accelerator grid shape at the start of ion engine operation using reverse-time simulation, using the grid shape at the desired lifetime as the initial condition for the reverse simulation. The calculations were performed by modifying the grid shape update program of the JIEDI tool. The reversibility of the simulation was verified by performing a forward-time simulation using the results obtained from the reverse-time simulation. This method allowed the determination of the initial accelerator grid shape that evolves to the target shape in a single calculation, eliminating the need for repeated trial and error adjustment of the initial grid shape. However, the results of numerical experiments show that the choice of the starting value has a significant influence on the lifetime of the accelerator grid. Furthermore, the grid aperture area tends to be large in the early stages of operation, leading to a degradation of the neutral confinement performance, highlighting the need for further improvements, such as setting appropriate starting values for the calculation.
https://ror.org/05qemrn04 
