# Layer coverage visualisation for a multi-region analysis
**URL:** https://discourse.paraview.org/t/layer-coverage-visualisation-for-a-multi-region-analysis/4055
**Category:** ParaView Support
**Created:** [April 13, 2020, 5:47pm UTC](https://discourse.paraview.org/t/layer-coverage-visualisation-for-a-multi-region-analysis/4055 "2020-04-13T17:47:03Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@JhnM](https://discourse.paraview.org/u/JhnM)
#### Post date: [April 13, 2020, 5:47pm UTC](https://discourse.paraview.org/t/layer-coverage-visualisation-for-a-multi-region-analysis/4055/1 "2020-04-13T17:47:03Z")
Hi !
I’m currently doing a thermal analysis on a sphere surrounded by air using the solver chtMultiRegionFoam and snappyHexMesh for the mesh. (OpenFOAM v1912)
When I am adding layers, I want to display the layer coverage on the sphere using Paraview and the filter “nSurfaceLayers”.
The “problem” is that the layers extruded belong to the region of the air so when I am applying the filter only on the internalMesh of the sphere, it says that there is no layers on the sphere which is logic. (picture attached)
But I really need to display in “3D” to have a better understanding of the coverage on the whole surface instead of using a slice (second picture attached).
Is there a filter/trick in Paraview to see the layer coverage on the sphere ?
I have uploaded the case just in case.
[sphere\_investigation.zip](https://discourse.paraview.org/uploads/short-url/gLZPZrpeZpxWsHPp70EzORmgZjP.zip) (2.2 MB)
Cheers,
PS : I am using Paraview 5.8
(OpenFOAM v1912)
 
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### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [April 14, 2020, 3:03am UTC](https://discourse.paraview.org/t/layer-coverage-visualisation-for-a-multi-region-analysis/4055/2 "2020-04-14T03:03:05Z")
> [@JhnM](#):
>
> the filter “nSurfaceLayers”.
This filters is coming from ParaFOAM, not ParaView, we can’t really help you with it.
Can you explain what you are trying to achieve ?
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### Author:  [@JhnM](https://discourse.paraview.org/u/JhnM)
#### Post date: [April 14, 2020, 7:58am UTC](https://discourse.paraview.org/t/layer-coverage-visualisation-for-a-multi-region-analysis/4055/3 "2020-04-14T07:58:13Z")
Well, what I want to achieve is to visualise the layer coverage on the sphere. The problem is the layers are not on the same region as the sphere so I cannot see them if I display only the internalMesh of the sphere.
So I was questioning myself whether there is a tool in Paraview to see this properly as I want to check the layer coverage on the whole sphere. (not with a slice)
Basically instead of having 0 layer on the first picture (sphere\_layers) I want to achieve for instance this:
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### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [April 14, 2020, 8:06am UTC](https://discourse.paraview.org/t/layer-coverage-visualisation-for-a-multi-region-analysis/4055/4 "2020-04-14T08:06:06Z")
That is indeed a specific operation. Your best bet may be to ask OpenFOAM about the nSurfaceLayers filter usage.
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### Author:  [@JhnM](https://discourse.paraview.org/u/JhnM)
#### Post date: [April 14, 2020, 8:09am UTC](https://discourse.paraview.org/t/layer-coverage-visualisation-for-a-multi-region-analysis/4055/5 "2020-04-14T08:09:16Z")
Ok, thanks for your help !