I baked my fluid simulation, and rendered. But every 15~20 frames the sim froze.

So I closed the Blender file, reload it again and render from the keyframe which was frozen. I think it's the directory(cache) problem?


This is another post with the same issue in 2008. I cannot believe it hasn't been fixed yet.. anyone has the same issue?

  • 2
    $\begingroup$ That's a third-party addon so it might be worth looking at their FAQ page and putting in a support request assuming it's the paid-for version.. $\endgroup$
    – John Eason
    Commented Oct 2, 2023 at 23:38

1 Answer 1


This type of issue can be caused by a known issue in Blender that can result in static renders, incorrect renders, and crashes when rendering a FLIP Fluids addon simulation.

The solution is to render from the command line which ensures a correct and stable render. The FLIP Fluids addon contains a sidebar operator for automatically setting up and launching a command line render here:

enter image description here

More information can be found in the FLIP Fluids addon documentation here: Why render from the command line?

Why render from the command line? There can be render instabilities in Blender that may cause crashes, result in incorrect renders, or result in whitewater particles not rendering when rendering FLIP Fluids addon simulations. This is caused by a design issue in Blender where the viewport and render threads do not sync correctly and can cause a crash (Issue T60094 and Issue T88811). This becomes more troublesome as amount of geometry increases. This issue is the reason why the viewport needs to be locked during render to improve stability. Rendering from the command line will bypass this design issue since the viewport is no longer needed.

Unfortunately this issue is outside of our control and will need to be fixed by the Blender developers. There is a comment here in the issue thread where a Blender developer mentions the design issues will need to be handled in regular development:

From Sergey: Currently it's as stable as we can make it. It is indeed true that interface is better be locked, otherwise render thread might cause conflicts with the viewport (due to python handlers possibly modifying data while it's being drawn by the viewport). There are ways around it, but needs some design changes. Will be handled outside of the bug tracker as a regular development.

This issue can be highly dependent on the system. Some artists will experience this issue frequently while others may never experience this issue. Due to this issue, we highly recommend becoming familiar with the command line rendering tools.

Another cause of this issue can be from other addons. If this issue persists after a command line render, try disabling other addons to narrow down the source of the issue.


You must log in to answer this question.

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