Unexpected Grain Morphology Changes in Neper During Spherical Defect Removal from Columnar Grain Models

[mike-J2023]

Hi everyone, when I use Neper to build a columnar grain model, I want to remove a spherical defect at the center of the model. However, I found that after the removal, the grain morphology of the model changed significantly—from the initial columnar grains to a mixed state of equiaxed and columnar grains. Below is the code I used for the cutting. Could you help me identify what might be causing the issue?
Thank you!

The following is the code I used to generate the columnar grain model:
neper -T -n 149 -domain "cube(100,100,100)" -morpho "gg,aspratio(14,14,43.6)" -ori random -oriformat plain -oridescriptor e -o n149 -id 1
The following is the code I used to add a transform cut on top of the columnar grain model generation:
neper -T -n 149 -domain "cube(100,100,100)" -morpho "gg,aspratio(14,14,43.6)" -ori random -oriformat plain -oridescriptor e -transform "cut(sphere(28,28,28,14))" -o n149 -id 1

[rquey]

There isn't any option related to a columnar structure in your command. However, it is true that columnar and -transform cut are not compatible. Cutting is done by seed mirroring, which won't work as expected for columnar grains. It will necessarily generate non-columnar grains as you've seen.

[mike-J2023]

Thank you for your answer. I obtained the columnar grain structure by elongating the grain along the Z-axis.The code is as follows:-morpho "gg,aspratio(14,14,43.6)"