Possible to simulate fountain jet to determinate it's shape and height?


#1

Hello!

I want to determinate the shape and the height of a fountain jet with a certain nozzle at a certain flow (like the simulation below made with ANSYS Fluent).

Is this possible with SimScale? If so, can I have some tips of what settings should I make?

Thank you!


#2

Hi @bogdanvladonica, this should definitely be possible with the multiphase simulation, you could start by looking at the water wall simulation by Milad. I know this is a lot different but I think it’s your closest example, but the community will be happy to help if you get stuck at any point.

Kind regards,
Darren


#3

Hey @bogdanvladonica!

Have you made any progress so far?

All the best!

Jousef


#5

Sorry for the late response but I was very busy with school and work. I’m now ready to continue.

When I create the mesh for my nozzle inside a bounding box, instead of my nozzle I get this (cross in the middle):

Can someone look to my project and see what is happening (Fan Nozzle 1.0)? I really don’t understand what settings are wrong…

Here is my nozzle:

What I try to obtain with this project is to see the shape and height of the water jet at certain water flow and pressure.


#6

Hey @bogdanvladonica,

I am not a CFD expert but can tell you that you are getting a cross because of the low mesh refinement settings over the nozzle surface. Try to give a reasonable amount of refinement to capture the features of the nozzle. Furthermore, I think you should also consider some refinements in the region where you will expect a drastic change in the flow. That can be done with a square sphere or cylinder refinement zones. Hope this helps.

Best,
Ahmed


#7

The ting is that I can’t find that setting. I inserted the same nozzle 100X bigger and it works so clearly the problem is my mesh size setting. I’m using Hex-dominant parametric.


#8

Hi @bogdanvladonica,

You can do so by selecting mesh refinements, setting a refinement level and then selecting the entire geometry.

Do link the project as well so others can take a look at it.

Cheers.

Regards,
Barry


#9

Here is the project:

https://www.simscale.com/projects/bogdanvladonica/fan_nozzle_1-0_6/

Note that I used the exact settings for a 100X bigger model (https://www.simscale.com/projects/bogdanvladonica/fan_nozzle_1-0_m/) and that worked out fine. Clearly the problem is the size. How do I reduce the mesh size but without increasing model size?


#10

Hi @bogdanvladonica,

The issue with the project is your material point is intersecting or inside the geometry. Re-position the material point outside of your normal sized geometry but within the domain and it should be fine.

Cheers.

Regards,
Barry


#11

The material point has not intersected the nozzle geometry. I movet just in case to a sure distance but still in the Background Mesh Box. Same results.


#12

Hi @bogdanvladonica,

I copied your project and you can see the two meshes here. There was no issue on my end so you should probably check carefully what you did wrong.

I meshed using both the parametric and automatic internal mesher with no issues on both.

Cheers.

Regards,
Barry


#13

Thank you for your help so far. Indeed on your copied project the mesh of the nozzle is correct but the background mesh box is very small. I need at least 10x10 meters because of the size of the jet. I copied your project, changed the size of the background mesh box back to 10x10 meters and the result is the same as before, no mesh for nozzle. I’m understanding something wrong maybe?


#14

Hi @bogdanvladonica,

I’m currently re-running with an increased bounding box length. Will let you know if it is successful.

Cheers.

Regards,
Barry


#15

Hi @bogdanvladonica,

I’ve increased the bounding box to 10m and maintained an overall cell size of 0.05m per cell and had no problems again. You do probably need to check through what the issue might be as I have been unable to replicate it on my end.

You will find the project here. Oh do note additional refinement and a mesh convergence study is needed as well so do keep that in mind before straight up using the mesh and obtaining results.

Cheers.

Regards,
Barry


#16

Thank you! So my mistake was inappropriate cell size setting.

I will try now to simulate the water jet. I’m really curious about the results.