Water isn't flowing

Question

1. Created the liquid domain cube. Domain type is liquid.
2. Created a fountain as effector.
3. Created a sphere. Fluid type: Flow type: liquid: Flow behaviour: inflow. Then I also made sure that the "Use flow" box has a tic mark.
4. I selected all the objects and scaled them.
5. Increased water resolution.
6. At first the water flew but since the resolution was greater than before, I selected frame dropping. Then resumed the animation time-line. Result: At first water flew a bit but got stuck at a position.
7. After that, to fix the issues I reselected all my settings and rescaled the dominant cube and tried to solve the issue. Result: This time, there's no water coming out of the sphere :') Question: How can I fix this?

Answer 1

When you have set the Domain to Cache > Type > Replay (which I guess is the case here, although you do not mention it), then the simulation is generated "on the fly" while you are playing it the first time. The next time it can play faster if it is already in the memory.

However, changing values erases the memory and makes Blender recalculate the asimulation again. But if you set Playback to Frame Dropping because you want it to play faster, then the simualtion has the problem: each frame is simulated based on the result of the previous frame. If frames are skipped, there is no simulation data to carry on with.

So in order to playback a simulation with Frame Dropping enabled, you have to either let it run slowly at first so that all frames can be calculated and are available in memory or switch the Cache > Type to Modular or All and bake the simulation before playing it.

But note, even with pre-simulated or baked fluid, with high resolutions even Frame Dropping might not get you real-time playback.