[Sataha]

I built several domains to calculate the an steam impingement from a orifice to a porous media.

But as soon as I finished the calculation. I fond a problem is that the mass flow from inlet is not equal to the out. As it is shown in the picture and it is marked as red. The outlet is 0 and I have checked the settings of CFX and I can not find any error.

The other results is just as I expected, such as temperature and viscosity. But I cannot find where is wrong about the mass flow.

Thank you for your help!

[-Maxim-]

please share more information about your project. Attach screenshots and your out-file.
Do you have defined the interfaces between the domains properly?

[Sataha]

Originally Posted by -Maxim-

please share more information about your project. Attach screenshots and your out-file.
Do you have defined the interfaces between the domains properly?

Thank you for your reply.

I have defined the interfaces between the domains, but I am not sure about if it is properly.

I have some supplementary information in the attachment.

The first pic shows the interface I set up. The yellow circle is the interface domain, which is the end of the orifice (orifice outlet). The second pic is the set up of inlet conditions.

[-Maxim-]

your ccl and/or out file would help us more The out-file is generated by the solver manager and has the same name as your res file.

[Sataha]

Originally Posted by -Maxim-

your ccl and/or out file would help us more The out-file is generated by the solver manager and has the same name as your res file.

the attachment is my out file and I deleted some loop interactions as it exceeded the size requirement of forum.

Thank you!

[Opaque]

Your solution has not converged yet.. Far from it.

You can check the mass imbalance for the domain "fabric backside" and "fabric front", and the continuity equation has not been fully satisfied.

In addition, the message for stopping the run says:

================================================== ====================
Termination and Interrupt Condition Summary
================================================== ====================

CFD Solver: Run duration reached
(Maximum number of outer iterations)

You ran out of iterations w/o achieving convergence.

[Sataha]

Originally Posted by Opaque

Your solution has not converged yet.. Far from it.

You can check the mass imbalance for the domain "fabric backside" and "fabric front", and the continuity equation has not been fully satisfied.

In addition, the message for stopping the run says:



You ran out of iterations w/o achieving convergence.

Thank you for your reply.

The file I uploaded is a pilot test with a low number of mesh to obtain the results quickly. So the the residuals did not converge. But I think it is enough to have a preliminary result. Further more, I have another calculation with a quite ideal convergence with 10^-5 residual.

The problem I met, is that I set the orifice inlet a mass flow rate(1.333e-3), and at the end of orifice, where is the interface with another domain, whose mass flow rate is 0! Other results is just as I expected, for example, the temperatture.

I have checked all the settings of my CFX Pre. But I cannot find the reason. Very gloomy.

[Opaque]

It is very difficult to help w/o looking at some diagnostics, and with limited information.

Have you looked at the flow near the interface of concern ? If you have 50% flow in one direction, and 50% in the opposite, the net mass flow is still 0.

Have you look at the mass imbalances throughout the system? i.e. look at every interface downstream.

What do the streamlines from the inlet look like ?

[-Maxim-]

DOMAIN INTERFACE: Default Fluid Porous Interface
Boundary List1 = Default Fluid Porous Interface in fabric Side 1
Boundary List2 = Default Fluid Porous Interface in fabric backside Side \
2,Default Fluid Porous Interface in fabric front side Side 2

Are you sure that this is right? Fabric backside 2 and fabric front side 2 are on the same side? Maybe you can share some screenshots of the whole piece so that we know what flows where.

Otherwise Opaque is right: your residuals are still too high and your imbalances are not under 1% yet. Especially

| P-Mass-fabric front | 2.6162E-05 | -1.4207% |

Those numbers should be way lower for an 'easy' case.

Maybe the number of iterations are not enough for the flow to "reach" the outlet. Streamlines can show you more

[Sataha]

Thank you all!

I have solved the problem. Actually, it is not solved, but searched in the site and I find a similar problem in:

http://www.cfd-online.com/Forums/cfx...-rate-cfx.html

The mass flow can not be observed at a certain point and it is have to be in a face at least.