# Solutions of generalized Poisson's equation on a 3D surface

**URL:** https://community.freefem.org/t/solutions-of-generalized-poissons-equation-on-a-3d-surface/100
**Category:** General Discussion
**Created:** [July 30, 2019, 12:33am UTC](https://community.freefem.org/t/solutions-of-generalized-poissons-equation-on-a-3d-surface/100 "2019-07-30T00:33:18Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Bob\_IDP](https://avatars.discourse-cdn.com/v4/letter/b/9dc877/32.png) [@Bob\_IDP](https://community.freefem.org/u/Bob_IDP)
#### Post date: [July 30, 2019, 12:33am UTC](https://community.freefem.org/t/solutions-of-generalized-poissons-equation-on-a-3d-surface/100/1 "2019-07-30T00:33:18Z")

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I have been solving the potential in a thin resistive film with electrodes on the surface of a cylinder by unwrapping it to a flat 2D problem and solving the generalized Poisson’s equation with a finite difference algorithm. I would like to consider more general curved surfaces, starting with the same topology of a cylinder, but stretched into things like a cone transition and such. I have tried to understand, whether FreeFEM can be used to solve on a general 3D surface that is tube like. Furthermore, the problem would then be made to be a multi-physics problem with the joule heating power dissipating into the substrate supporting the film, first steady state solutions, but late a full time varying heat equation solutions. Can anyone tell me if the 3D surface mesh solution is possible in FreeFEM and if so, then possible give me example or a direction to take to start?

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### Author: ![AFourmont](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/afourmont/32/56_2.png) [@AFourmont](https://community.freefem.org/u/AFourmont)
#### Post date: [July 30, 2019, 4:01pm UTC](https://community.freefem.org/t/solutions-of-generalized-poissons-equation-on-a-3d-surface/100/2 "2019-07-30T16:01:51Z")

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You can find more informations about the 3d surface mesh here [https://doc.freefem.org/documentation/mesh-generation.html#the-type-meshs-in-3-dimension](https://doc.freefem.org/documentation/mesh-generation.html#the-type-meshs-in-3-dimension)  
and find some examples in the directory examples/3dSurf of the distrib.