Trying to achieve high pressure water with Mantaflow

Hi. I have been following different tutorials. Even step by step explanation of each parameter. Still have some questions since the tutorials on youtube…are all mainly focused in making a sphere emit water and fill a tank.

I need to simulate a high pressure hose under a swimming pool emitting water against the bottom. The first thing I am struggling a little bit is how much time each simulation consumes. I am aware is a slow process, but I can not see any result unless I use 256 resolution divisions in my domain.

First question: Does the resolution of my inflow object counts? I am using a torus but kind of low poly…If I increase my subdivision will I be able to see results without needing to crank my domain resolution to 256 ?

Second question: Is there anyway to avoid my inflow / stream water as rings? The fluid simulation shows the particles in a ring manner (analogous to the tours), I am thinking how to avoid this ans actually have a high pressure flow without having those spaced rings coming from the torus.

Third and most important: After the fluid particles hit the bottom of my domain the water flow/stream spreads inside the domain, watersplash kinda…but I need to preserve somehow the pressure…I am looking for the effect that the pressure washers for cars generate when hitting to the car surface.

Which parameter will help me to “preserve” the particle pressure…I understand some particles need to spread cause they get lost, but I would like to control the flow -

I am asking this cause maybe someone already tested something similar and I can save some hours testing parameter alterations…

Althought in reality the materials may change their state on abnormal situations, i.e. pressure can also turn a gas into a liquid or into a solid, not just its temperature; Simulations are still a bit conservative in their main attributes/variables.

In this ‘pressure hose’ situation, perhaps a mixture of physical particles and smoke would be faster to setup and simulate. Mantaflow alone is not the best solution for such setup.

I am not sure exactly why “gas” came to the equation. To say it in different words I am trying to guide the water and make it bounce a little bit against a surface. One of the problems I have is the water dying after touching a surface. So It is hard to make it bounce. The other issue is I am not being able to guide it…cause I will like the water after touches the bottom surface and bounce start to go up…like being underwater. I am trying with the “guide” parameter, but no luck yet. It works like a magnetetic force kind of…but I want to literally guide the water via curves or something that allows me to control the direction.

Maybe you are right and it is better to use a particle system and maybe metaballs…to simulate the water.

Yes, there’s definitely a minimum resolution for your obstacles to be part of the simulation, and more resolution tends to make more detail and make the fluid feel larger and more “real”.

I can not see any result unless I use 256 resolution divisions in my domain.

Try making your domain and inflow/effectors much larger (scale it up by 5 or 10, then select all, CTRL+A and Apply Scale - this is important). I think this is a bug where domains smaller than like 1m or 2m don’t behave properly. With the bigger domain, it should work fine with smaller resolution.

Could you post an image of your setup? I’m having a hard time picturing your setup with the hose. Is it already underwater?

Is there anyway to avoid my inflow / stream water as rings?

Yeah, use a different object for inflow. The resolution isn’t so important as it will just come from the mesh. You can use the sampling steps in the Inflow object settings to make the stream smoother (important when it’s fast like this).

I’d suggest putting your inflow object inside of a tube-shaped obstacle with one end open to use as the hose. You can then give it some initial velocity pointing the way you want, plus the object velocity to generate pressure inside the tube. That’s important to get that high velocity flow, rather than just a gentle drip.

Example: https://imgur.com/s7F3Pbs

This is just Resolution = 100, with Sampling Substeps = 3 for the Inflow sphere. Initial velocity is -2m/s in Z and object velocity of 1.00.