# Improving mesh quality of hex mesh (for IGA)

Hi Cubiteers

I’m trying to get a quality hex mesh of the problem below;

The issue is largely around the lozenge shaped holes in my geometry, I’ve tried a range of things to get high quality mesh, but those tricky holes keep making elements with a very low jacobian. What should my strategy be, what could I try?

Thanks

Andy

Given this mockup:

I would try more webcutting into something like:

Then the pave algorithm should produce a fairly nice discretization on these elliptical regions,

or you might try the polyhedron scheme on these elliptical regions

though it may require a higher mesh density to reach a good quality with the polyhedron scheme for this problem:

``````reset

create surface circle radius 1 zplane
create surface circle radius 1.25 zplane
subtract vol 1 from vol 2
compress

move Surface 2 y 1.125 include_merged
Surface 2 copy rotate 12.5 about z repeat 2
Surface 2 copy rotate -12.5 about z repeat 2
subtract vol 2 3 4 5 6 from vol 1

webcut volume 1 with plane xplane offset 0
webcut volume 1  with plane xplane offset 0 rotate {-12.5 * 1/2} about z center 0 0 0
webcut volume 1  with plane xplane offset 0 rotate {-12.5 * 2/2} about z center 0 0 0
webcut volume 1  with plane xplane offset 0 rotate {-12.5 * 3/2} about z center 0 0 0
webcut volume 1  with plane xplane offset 0 rotate {-12.5 * 4/2} about z center 0 0 0
webcut volume 1  with plane xplane offset 0 rotate {-12.5 * 5/2} about z center 0 0 0

webcut volume 7  with plane xplane offset 0 rotate {12.5 * 5/2} about z center 0 0 0
webcut volume 7  with plane xplane offset 0 rotate {12.5 * 4/2} about z center 0 0 0
webcut volume 7  with plane xplane offset 0 rotate {12.5 * 3/2} about z center 0 0 0
webcut volume 7  with plane xplane offset 0 rotate {12.5 * 2/2} about z center 0 0 0
webcut volume 7  with plane xplane offset 0 rotate {12.5 * 1/2} about z center 0 0 0
compress

webcut volume 2 3 4 5 6 7 9 10 11 12 with cylinder radius 1.125 axis z

imprint all
merge all
mesh surf all
``````