Hello, I know in tally input CellFilter is used for calculating tally data in a certain cell volume. Now, for a certain cell, the score “flux” gives the total flux of the cell volume.

Now, if I want to use a mesh (dividing the cell into small portions) and want to calculate the flux for each mesh. This is not a problem if the cell is rectangular with (two or three dimensions). I can use a normal mesh with my dimension, lower-left, and upper-right.

Now, if the cell is a cylinder, currently I also can use a rectangular mesh with (x,y,z) dimensions that cover the cylinder, I can use the CellFIlter, MeshFilter together and can get the tally data for each mesh for a cell. Below is an example where 0.39218 is the radius of the cylinder. **Is this the correct way I am using it?**

mesh2 = openmc.Mesh(mesh_id=2)

mesh2.type = ‘regular’

mesh2.dimension = [10, 1, 1]

mesh2.lower_left = [-0.39218, -0.39218, -3]

mesh2.upper_right = [0.39218, 0.39218, 3]

mesh_filter2 = openmc.MeshFilter(mesh2)

cell_filter1 = openmc.CellFilter(fuel)

energy_filter = openmc.EnergyFilter([0., 4., 20.e6])

tally2 = openmc.Tally(tally_id=2, name=‘tally 2’)

tally2.filters = [energy_filter, cell_filter1, mesh_filter2]

tally2.scores = [‘flux’, ‘fission’, ‘nu-fission’]

**My problem is. What is the cylinder is an angular cylinder (say 45-degree angular from x-axis)? How to define the mesh (angular mesh) in that case that will cover the cylinder cell and divide into small portion according to the mesh dimensions.**

**Now, I can only use the cell filter for this kind and get the total flux tally for that cell. I want to use a mesh and device the cell into small portion and get the flux value in each portion.** Any help regarding this is highly appreciated. Thank you.

Regards,

Sharif Abu Darda