# Voronoi in 3DEC 5.2 **URL:** \ **Category:** 3DEC\ **Tags:** faq\ **Created:** [April 7, 2022, 9:47am UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422 "2022-04-07T09:47:41Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![Akash77skyz](https://avatars.discourse-cdn.com/v4/letter/a/8dc957/32.png) [@Akash77skyz](https://forum.itascainternational.com/u/Akash77skyz)\ **Post date:** [April 7, 2022, 9:47am UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/1 "2022-04-07T09:47:41Z")
Hello everyone. Can anyone tell me whether we can use or create Voronoi elements in 3DEC 5.2 and show minor fractures? In my case I have to simulate a cylindrical specimen with very small Voronoi elements for the UCS test and record the shear failure damage pattern. Can the poly option in 3DEC 5.2 do this? Thank you. ---
**Author:** ![jmswdmn](https://avatars.discourse-cdn.com/v4/letter/j/51bf81/32.png) [@jmswdmn](https://forum.itascainternational.com/u/jmswdmn)\ **Post date:** [April 7, 2022, 2:49pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/2 "2022-04-07T14:49:58Z")
I believe Voronoi generation was brought in for 3DEC v7. You could generate them with a different software and import them to 3DEC if you wanted though? e.g. [https://neper.info/](https://neper.info/) and publications e.g. [Ghazvinian et al. 2014](https://www.sciencedirect.com/science/article/pii/S1674775514000808) ---
**Author:** ![pprasad](https://avatars.discourse-cdn.com/v4/letter/p/e19b73/32.png) [@pprasad](https://forum.itascainternational.com/u/pprasad)\ **Post date:** [April 8, 2022, 5:02pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/3 "2022-04-08T17:02:00Z")
@jmswdmn , I generated elongated voronoi tesselation in _neper_ and trying to import into 3DEC. The probem is that the actual geometry is not reatined after importing into 3DEC. ```auto model new geometry import 'uni.stl' block generate from-geometry ``` I could not figure out what I am missing here. Are tesselation facets triangulated because the file format is .stl? Apprecitaed if you can give insight on this. ![uni](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/8f0d2e24a1617a8b4e92f3fa1d8639be1aa1a1e8.png) Neper tesselation ![uni_3dec_geometry](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/6ca0621cc5f744069571918b133910f0e4c8a061.png) Geometry 3DEC ![uni_3dec_blocks](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/ee7a1f4a827ae6545a7bbb4cb5e503252184965b.png) Blocks 3DEC ---
**Author:** ![jmswdmn](https://avatars.discourse-cdn.com/v4/letter/j/51bf81/32.png) [@jmswdmn](https://forum.itascainternational.com/u/jmswdmn)\ **Post date:** [April 8, 2022, 5:43pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/4 "2022-04-08T17:43:24Z")
checked and solved with @pprasad offline… for others benefit `block generate from-geometry merge` correctly generates the blocks from the .stl ![uni_3dec_geometry_correct](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/b9ff84614fb8b6f6a476801852dda4afc1af0df6.png) ---
**Author:** ![Akash77skyz](https://avatars.discourse-cdn.com/v4/letter/a/8dc957/32.png) [@Akash77skyz](https://forum.itascainternational.com/u/Akash77skyz)\ **Post date:** [April 15, 2022, 2:45am UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/5 "2022-04-15T02:45:47Z")
@jmswdmn can you tell me if I do the same in 3DEC 5.2, what will be the command for generating the block from the .stl geometry file with proper merge? Thank you. new geometry import ‘geometry.stl’ ?? ---
**Author:** ![jhazzard](https://avatars.discourse-cdn.com/v4/letter/j/4af34b/32.png) [@jhazzard](https://forum.itascainternational.com/u/jhazzard)\ **Post date:** [April 15, 2022, 1:09pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/6 "2022-04-15T13:09:47Z")
There is no generating from geometries in 5.2. And there is no merge in 5.2. These are both new features in v7. ---
**Author:** ![Akash77skyz](https://avatars.discourse-cdn.com/v4/letter/a/8dc957/32.png) [@Akash77skyz](https://forum.itascainternational.com/u/Akash77skyz)\ **Post date:** [April 15, 2022, 1:31pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/7 "2022-04-15T13:31:04Z")
@jhazzard I have sent the pictures of my voronoi geometry. How can I turn it into smaller blocks in 5.2? Is there a way? Thank you. ![12234](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/2aaaa022e74fae7f50a293f174642ce5ca424509.png) ![44444](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/6e5113683e0891c38a187617cf63f9722ae9ba58.png) ![22222](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/f21b73f30f4d470e00f8ce10616c194d4cee9c95.png) ---
**Author:** ![jhazzard](https://avatars.discourse-cdn.com/v4/letter/j/4af34b/32.png) [@jhazzard](https://forum.itascainternational.com/u/jhazzard)\ **Post date:** [April 15, 2022, 1:52pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/8 "2022-04-15T13:52:07Z")
You can try the densify command, but note that 3DEC 5.2 is no longer officially supported. ---
**Author:** ![Akash77skyz](https://avatars.discourse-cdn.com/v4/letter/a/8dc957/32.png) [@Akash77skyz](https://forum.itascainternational.com/u/Akash77skyz)\ **Post date:** [April 16, 2022, 8:25am UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/9 "2022-04-16T08:25:33Z")
@jhazzard Yes, sorry for the trouble about 5.2. The thing is as mentioned by @jmswdmn about the research paper [3D random Voronoi grain-based models for simulation of brittle rock damage and fabric-guided micro-fracturing - ScienceDirect](https://www.sciencedirect.com/science/article/pii/S1674775514000808) , I see they used an older version of 3DEC, not 7. But I see they changed the geometry to block like the voronoi ones through an .stl file using neper and did some good simulations. I used the densify command as you said, but since no blocks, its only a geometry, so it did not cut anything. I was hoping I could turn this voronoi cylindrical .stl geometry (shown in the pictures) to a similar bonded cylindrical block in 3DEC 5.2. Because 3DEC cannot do simulation with geometry (like showing displacement,etc ), need it to be changed into block. Thank you very much for the suggestions and help. ---
**Author:** ![jmswdmn](https://avatars.discourse-cdn.com/v4/letter/j/51bf81/32.png) [@jmswdmn](https://forum.itascainternational.com/u/jmswdmn)\ **Post date:** [April 17, 2022, 6:00pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/10 "2022-04-17T18:00:41Z")
i have not tried it, but the neper tessellation module has a .3dec file output option rather than .stl. see documentation here: [Tessellation Module (-T) — Neper 4.4.1 documentation](https://neper.info/doc/neper_t.html?highlight=3dec#output-files) ---
**Author:** ![pprasad](https://avatars.discourse-cdn.com/v4/letter/p/e19b73/32.png) [@pprasad](https://forum.itascainternational.com/u/pprasad)\ **Post date:** [April 19, 2022, 7:38pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/11 "2022-04-19T19:38:46Z")
I tried it but could not find a way to import the file with extension ‘.3dec’. As per the doccumentation, `geometry import` command takes ‘.dxf’,’.geom’ and ‘.stl’ formats as inputs, not sure about ‘.3dec’. The _ **neper** _ exported `'.3dec'` file looks like this (also attached the original file) ```auto poly reg 1 & face ID 1 -0.000000000000 0.156028620036 0.385483743894 & -0.000000000000 0.166461528444 0.511596225269 & 0.000000000000 0.144136915260 0.589230695416 & -0.000000000000 -0.000000000000 0.550621759629 & -0.000000000000 -0.000000000000 0.422613510521 & face ID 2 0.645406302159 0.000000000000 0.495792091901 & -0.000000000000 -0.000000000000 0.422613510521 & -0.000000000000 -0.000000000000 0.550621759629 & 0.355209870397 -0.000000000000 0.574514228627 & face ID 3 0.355209870397 -0.000000000000 0.574514228627 & 0.347186195422 0.075285272124 0.582467867837 & 0.766668683548 0.150244902834 0.479134074405 & 0.645406302159 0.000000000000 0.495792091901 & face ID 4 0.347186195422 0.075285272124 0.582467867837 & 0.355209870397 -0.000000000000 0.574514228627 & -0.000000000000 -0.000000000000 0.550621759629 & 0.000000000000 0.144136915260 0.589230695416 & 0.116869858912 0.147063635430 0.590999217745 & ``` This doesn’t look like a `.3dgrid` file to be imported using `block import` command. [uni.zip](https://forum.itascainternational.com/uploads/short-url/69wYuupPmJDFtAknc8UAdXxGNt2.zip) (31.8 KB) ---
**Author:** ![jmswdmn](https://avatars.discourse-cdn.com/v4/letter/j/51bf81/32.png) [@jmswdmn](https://forum.itascainternational.com/u/jmswdmn)\ **Post date:** [April 19, 2022, 8:16pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/12 "2022-04-19T20:16:24Z")
yes, this works for import into v5.2 with `call` command ![uni_3dec](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/07c58f462e7c20631393b34ec80acc49edfc16c6.png) ---
**Author:** ![pprasad](https://avatars.discourse-cdn.com/v4/letter/p/e19b73/32.png) [@pprasad](https://forum.itascainternational.com/u/pprasad)\ **Post date:** [April 19, 2022, 8:47pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/13 "2022-04-19T20:47:27Z")
Have you just imported the ‘.3dec’ file? Would you mind providing the full command you have used that ? Thank you, ---
**Author:** ![jmswdmn](https://avatars.discourse-cdn.com/v4/letter/j/51bf81/32.png) [@jmswdmn](https://forum.itascainternational.com/u/jmswdmn)\ **Post date:** [April 19, 2022, 9:08pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/14 "2022-04-19T21:08:05Z")
```auto model new call 'uni.3dec' ``` note: as requested above, v5.2, not v7. ---
**Author:** ![pprasad](https://avatars.discourse-cdn.com/v4/letter/p/e19b73/32.png) [@pprasad](https://forum.itascainternational.com/u/pprasad)\ **Post date:** [April 19, 2022, 9:12pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/15 "2022-04-19T21:12:03Z")
I see. It won’t work in v7. Thank you. ---
**Author:** ![jhazzard](https://avatars.discourse-cdn.com/v4/letter/j/4af34b/32.png) [@jhazzard](https://forum.itascainternational.com/u/jhazzard)\ **Post date:** [April 20, 2022, 3:33pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/16 "2022-04-20T15:33:22Z")
You can convert the 5.2 data file to version 7 format. Just open the file in 3DEC 7 and go to Edit - 3DEC Command Conversion. It may take a while for a big file, but you only need to do it once. ---
**Author:** ![pprasad](https://avatars.discourse-cdn.com/v4/letter/p/e19b73/32.png) [@pprasad](https://forum.itascainternational.com/u/pprasad)\ **Post date:** [April 20, 2022, 5:39pm UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/17 "2022-04-20T17:39:41Z")
That works perfectly. Thank you. ---
**Author:** ![uncleyuan](https://avatars.discourse-cdn.com/v4/letter/u/f17d59/32.png) [@uncleyuan](https://forum.itascainternational.com/u/uncleyuan)\ **Post date:** [May 4, 2022, 9:48am UTC](https://forum.itascainternational.com/t/voronoi-in-3dec-5-2/422/18 "2022-05-04T09:48:11Z")
hello, not the .stl results in the tetrahedral blocks， but the command ‘block generate from-geometry’ results in the tetrahedral blocks in the same way as griddle dose.