Some numerical wear tests are conducted for the carbon/carbon ion optics of a microwave ion thruster μ10 engineering model to evaluate tbe accuracy and precision of JAXA's ion optics code (JIEDI). Through comparisons with experiment, the JIEDI code showed good agreement with a real-time 18,000-hrs life test when incorporating the motion of eroded grid materials and a low-energy sputtering yield model for the energy below 300 V. Numerical error caused by the uncertainty of physical model is also studied and it is found that uncertainty in beam current and plasma parameters cause 10% or less error to estimate grid hole erosion profiles. The grid erosion profile is most sensitive to the uncertainty in sticking factor, which indicates what percentage of eroded grid material arriving at a grid surface will re-deposit onto the grid surface.
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