# How to access normal vectors of each discretised tetrahedron element

**URL:** https://community.freefem.org/t/how-to-access-normal-vectors-of-each-discretised-tetrahedron-element/948
**Category:** General Discussion
**Created:** [April 26, 2021, 4:11pm UTC](https://community.freefem.org/t/how-to-access-normal-vectors-of-each-discretised-tetrahedron-element/948 "2021-04-26T16:11:18Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![Daokun](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/daokun/32/522_2.png) [@Daokun](https://community.freefem.org/u/Daokun)
#### Post date: [April 26, 2021, 4:11pm UTC](https://community.freefem.org/t/how-to-access-normal-vectors-of-each-discretised-tetrahedron-element/948/1 "2021-04-26T16:11:18Z")

</div>

Dear all,

I am trying to apply a variable compressive body force to a 3D cantilever model. The compressive force has no certain direction in a global scale.So I am trying to apply this compressive force on faces of each discretised tetrahedron element .Is there any way to access the normal vectors of each tetrahedron element?