[nha1g08]

Hello,

I am trying to simulate a 3d flow going through a nozzle, and into a chamber

Here is the geometry:

geometry.jpg

and here is the mesh

mesh.jpg

But when i run it in fluent i get the following result

result.jpg

The flow does not go through the nozzle, when i clearly defined the boundary condition for the outlet face to be a 'pressure outlet'.

Why is it not going out?

I also dont know why but the the same outlet face is defined by three faces, i set all three faces to be a pressure outlet. For example face 3, face 7, face 18 are in fact the same face as the nozzle exit. Could this be the problem?

[nha1g08]

can anyone help?

[Nickul]

bit late but hey, You should set the outlet face to an interior, as it is now with the nozzle exit face set as a pressure outlet it is able to freely exit the domain, not what you want at that point. Make sure their is one face at the nozzle exit, or more accuratley one interior face common to the nozzle interior and your ambient domain, not two faces belonging to each volume on top of one another, then when coming from Gamble , fluent will turn them into walls.

[nha1g08]

thanks for the reply Nickul, yes I did set it to interior and it solved the problem.

[Simon0114]

Hi,I'm making a project the same as yours,I set the boundary conditions refering to some papers,but the solution is always diverged,so can you give me some help on the boundary conditions setting,thanks

[nha1g08]

hello, are you trying to simulate vortex rings?

[Simon0114]

Originally Posted by nha1g08

hello, are you trying to simulate vortex rings?

no,I just simulate a 3D flow through a nozzle,mainly simulate the flow in the ambient,the ambient was simplified to a cube,just as a chamber like yours