I'm working on a simulation of a fluid surface in a model "river bed". My aim is to study the development of the surface pattern over time during flow.

I'm new to Blender - so here is my basic (maybe stupid question): Is it possible in Blender to get the data of the interface between water and air in a table (x/y/z) during all the (or at least many) timesteps of the simulation?

Thanks in advance.

Update: Sorry for the unclear post. I have not started to work in Blender yet (so I cannot provide any results), I just wanted to investigate if there is a chance to get the data as needed (in table form as mentioned above).

The aim is to develop a water "flow sensor" that can detect patterns on the surface. I want to investigate how certain patterns develop in time, dependent on (water speed / amount of water / shape of river bed ...). I'd be happy to get any help on setting up the model in a second stage.

Thank you again.

  • $\begingroup$ Can you please add a screenshot so that I know exactly what is going on? $\endgroup$ Jan 3, 2018 at 23:05

1 Answer 1


You can export or access the simulation data in many ways:

  • obj or other mesh formats that gives you surface vertices locations per frame. Depending on your application you can use a Shrinkwrap modifier and a subdivided plane to keep the vertex count constant between frames

  • render Z-depth images of the surface from camera from above, giving you every visible surface point location in space (this has same limitations as that shrinkwrap trick)

  • you can use python and scripting to generate any custom data you want and to export it. With python api you can for example cast rays where you need to sample the surface and measure distances

One thing to note is that Blender's fluid simulation is meant for visuals, it is not meant to be scientifically accurate. You may find that in real world the fluid behaves a bit differently.

  • $\begingroup$ Jerryno, using the Z-depth image is a very clever way to extract the surface data. Thanks for sharing that answer. $\endgroup$
    – Ed Tate
    Jan 5, 2018 at 3:32
  • $\begingroup$ Jerryno, thank you very much for your answer - and sorry about not writing earlier. Too much to do :-( $\endgroup$
    – user50476
    Jan 17, 2018 at 9:48
  • $\begingroup$ @Jerryno In the meantime, I was successful in setting up the fluid simulation in the channel. Could you point me to a tutorial / help page to one of your options ? I could not find anything about the z-depth images, this seems to be the best way to proceed for me ... $\endgroup$
    – user50476
    Jan 17, 2018 at 9:55
  • $\begingroup$ @user50476 similar to this: blender.stackexchange.com/a/46756/7777. You can use the normalize node or not, it depends what you do with the data. Use orthographic camera, not perspective. $\endgroup$ Jan 17, 2018 at 10:30

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .