Simulating fluid movement on a small scale

[Jake]

Hello. For a research project, I am using Mantaflow inside Blender to model the movement of fluid inside an Erlenmeyer flask as the flask sits on a rotary flask shaker (commonly found in research labs).

After a preliminary trial, I was able to model the fluid as the flask moved in a continuous circular path in the Blender environment. However, when I modified my Blender domain, effector, and inflow so that they were all to scale (the bottom of the flask is about 10 cm, for reference), the simulation could not operate. I assume the Mantaflow solver can not function at such a small scale, however I need to figure out what my next steps are so that I can still manipulate the fluid’s behavior to mimic the real-world fluid behavior on the smaller and accurate scale.

I am looking into how I can vary non-dimensional parameters like the Reyolds number and others to improve my simulation’s accuracy. In the meantime, I thought I would also post on this forum to ask if anyone else has experience with running Mantaflow on small scales and if there are various parameters inside Blender that can be utilized to better model the fluid motion to better replicate the real-world, small-scale behavior.

Please let me know if there is anything needing clarification. Thanks for your time.

[thu...@gmail.com]

Hello, yes - generally it's a good idea to rescale your problem such that you can use a setup similar to the default unit cube in Blender. You can compute the right units from the parameters of your problem, most importantly probably the Reynolds number.

And regarding viscosity settings , I can recommend the blender documentation:

https://docs.blender.org/manual/en/latest/physics/fluid/type/domain/liquid/diffusion.html?highlight=viscosity

I hope that helps a bit!