Mesh Two Excised Spheres from Sphere

Hello,

I’ve been able to mesh a single sphere with an excised sphere (which is essentially just a hollow sphere) by cutting my volume into 8 octants. I can also use the Subtract boolean to remove two spheres from a larger single sphere, however I have been unable to mesh this. I would prefer to use the Sweep meshing scheme.

Is this geometry meshable easily?

Thanks for the help,

Can you send us a journal file so we can see the placement of the spheres with respect to each other?

Here is a typical example of a domain which will need to be meshed. I tried using plane cuts through both excised spheres in all 3 dimensions (leaving 12 regions), but the regions between the excised spheres wouldn’t mesh for me.

Thanks for taking a look,

The journal file below shows one way to mesh your sphere with the 2 sphere cut-outs. You can change the aprepro variables at the top of the journal file to specify a smaller/larger size as fits your analysis needs.

reset
#{_meshsize=0.75}
#{_core_curve_intervals=2}

create sphere radius 1
move Volume 1 x -10 y 0 z 0 include_merged
create sphere radius 2
move Volume 2 x 5 y 0 z 0 include_merged
create sphere radius 20
subtract volume 1 2 from volume 3

webcut vol all plane xplane

webcut volume all with cylinder radius 10 axis x
webcut volume 10 with cylinder radius .5 axis x
webcut volume 8 with cylinder radius 1 axis x

create volume loft surface 39 31
unite volume 13 8
unite volume 12 10
webcut volume 13 with sheet extended from surface 46
webcut volume 12 with sheet extended from surface 46
delete volume 15

webcut volume 7 9 12 13 plane yplane
webcut volume 7 9 12 13 18 19 20 21 plane zplane
imprint vol all
merge vol all

vol all size {_meshsize}

curve in surf 41 51 28 42 29 58 52 int {_core_curve_intervals}
mesh volume 11 17 16 14

Surface 172 129 140 182 135 184 174 133 154 196 186 142 scheme pave
mesh surface 172 129 140 182

volume all redistribute nodes off
volume 24 scheme Sweep source surface 140 target surface 135
volume 28 scheme Sweep source surface 182 target surface 184
volume 25 scheme Sweep source surface 140 target surface 154
volume 29 scheme Sweep source surface 182 target surface 196
volume 12 scheme Sweep source surface 129 target surface 133
volume 13 scheme Sweep source surface 129 target surface 142
volume 20 scheme Sweep source surface 172 target surface 174
volume 21 scheme Sweep source surface 172 target surface 186
mesh volume 24
mesh volume 28
mesh volume 25
mesh volume 29
mesh volume 12
mesh volume 13
mesh volume 20
mesh volume 21

surf 69 59 155 163 119 111 60 70 scheme pave
vol with not is_meshed scheme sweep
mesh vol with not is_meshed