Learning Forum

[s_singh2]

Hello Everyone, I am doing a project on Horizontal film boiling. I follow the tutorial available on the internet but whenever i try to run the calucation fluent will automatically closes and workbench shows the message as follows:

Failed in handling Cortex/Fluent command messageWorkBench Error: Could not register file; Name :SYS-1.cas.h5; Type :caseError Occured during handling message in WorkBench: An error occurred in FLUENT during execution of an internal command
An error occurred in FLUENT during execution of an internal command

Failed in handling Cortex/Fluent command messageWorkBench Error: Could not handle event: SolutionGridCheckError Occured during handling message in WorkBench: An error occurred in FLUENT during execution of an internal command
An error occurred in FLUENT during execution of an internal command

Please help me to solve this error.

I use VOF model taking water liquid and water vapor as material.
For heat and mass transfer udf i use the code whose link as given below:
https://innovationspace.ansys.com/forum/forums/topic/film-boiling/

[Rob]

If you launch Fluent in standalone mode what happens? You may need to export the Fluent case from Workbench. Can you run other models?

[s_singh2]

Thankyou for the reply. If I launch fluent throungh CMD CD and try to run the case file it will exit the application automatically, and shows above error if i launch fluent through workbench. I try to simulate nucleate boiling and it run and shows result.

[Rob]

And with a different case file? It's not clear whether you have an installation issue in that Fluent won't run or a model issue. 

[s_singh2]

Sir, Thankyou for helping me. My mesh is completely loaded in the fluent. There is no problem in my mesh. When i try to run the calulation the fluent window will shut down automatically and the workbecnch shows the error which i mentioned above. As you suggested i try to do some other simulation( nucleate boiling) and and it calculate completely and shows the result.
I put some pictures of film boiling which shows the problem.

[Rob]

Film boiling in 2d? 

[s_singh2]

Yes, sir

[Rob]

Please show an image of the multiphase panels & tabs. 

[s_singh2]

These are my settings

[Rob]

What phase interaction did you set?

[s_singh2]

These are my phase interaction:

 

Then I compiled the udf which i pasted from this forum :https://innovationspace.ansys.com/forum/forums/topic/film-boiling/

In function hook i select my init function::libudf in the Initialization and area density::libudf in the Adjust.

In memory i give 3 to the memory location.

My cell boundary condition are as :

 Same settings for liquid also.

In boundary condition > wall> thermal> temperature> and in temperature column i gave 383.

In boundary condition>outlet( phase: mixture)>thermal> backflow temp: 373K.

In boundary condition>outlet( phase: fluid)>multiphase> backflow volume fraction: 1.

Reference values:

 Solution methods:

 Solution Controls:

 Initilization:

 I make a custom function(linear function) for temperature variation along y direction in mesh and patch it:

0

 When i try to solve it it automatically closes.

Help me what I have done wrong.

[Rob]

Turn off the UDF and see what happens. You've not got any mechanism for the phase mass exchange. The UDF also uses UDMs, have you assigned those?

[s_singh2]

Yes, I assigned UDM = 3.

If i turned off the udf my cell boundary condition which is based on udf will not work. Whatever function I assigned to function hook is also invalid. Then how can I solve this.

You also mentioned that i dont have any mechanism for the phase mass exchange what i have to do for this.

[Rob]

If you want boiling you need to set a phase mass exchange - it's in phase heat & mass transfer tab. Similarly, if you're not sure about boiling you may want to review the UDF very carefully: UDFs are not something I'd start with. 

[s_singh2]

I actually found inernet if I Launch fluent using "Cross Tool Command Prompt for VS", it might solve the problem. So i did the same. Now my fluent window will not automatically closed and it give me some error. Please help how I solve this error.

[Rob]

Click No, and then scroll up to see if the error is useful. 

[s_singh2]

IIt shows this error:

Error in the fluent (fl) process : ended abnormally

 

Operation stopped.

 

Operation stopped.

 

===================================================================================

= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES

= RANK 0 PID 1520 RUNNING AT DESKTOP-2GE7CNR

= EXIT STATUS: -1 (ffffffff)

===================================================================================

 

===================================================================================

= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES

= RANK 1 PID 15640 RUNNING AT DESKTOP-2GE7CNR

= EXIT STATUS: -1073740791 (c0000409)

===================================================================================

 

===================================================================================

= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES

= RANK 2 PID 2220 RUNNING AT DESKTOP-2GE7CNR

= EXIT STATUS: -1073740791 (c0000409)

===================================================================================

 

===================================================================================

= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES

= RANK 3 PID 4092 RUNNING AT DESKTOP-2GE7CNR

= EXIT STATUS: -1 (ffffffff)

===================================================================================

[Rob]

Which is probably linked to the UDF. 

[s_singh2]

 

Yes, you are right sir. I have checked my udf and found out where error occur but i didn’t know how to solve it.
This is my finction (a part of udf)

DEFINE_ADJUST(area_density, domain)

{

    Thread *t;

    Thread **pt;

    cell_t c;

    Domain *pDomain = DOMAIN_SUB_DOMAIN(domain, 0);

    real voidx, voidy, voidz = 0;

    Message(“Entering DEFINE_ADJUST(area_density)…\n”);

    if (pDomain == NULL) {

        Message(“Error: Sub-domain P_PHASE not found.\n”);

        return;

    }

    Alloc_Storage_Vars(pDomain, SV_VOF_RG, SV_VOF_G, SV_NULL);

   

    Scalar_Reconstruction(pDomain, “vof”, SV_VOF, -1, SV_VOF_RG, NULL);

    Scalar_Derivatives(pDomain, “vof”, SV_VOF, -1, SV_VOF_G, SV_VOF_RG, Vof_Deriv_Accumulate);

    Alloc_Storage_Vars(domain, SV_T_RG, SV_T_G, SV_NULL);

    T_derivatives(domain);

    Free_Storage_Vars(domain, SV_T_RG, SV_NULL);

    mp_thread_loop_c(t, domain, pt) {

        if (FLUID_THREAD_P(t)) {

            Thread *tp = pt[P_PHASE];

            begin_c_loop(c, t) {

                #if RP_3D

                C_UDMI(c, t, 0) = (C_VOF_G(c, tp)[0] * C_T_G(c, t)[0] + C_VOF_G(c, tp)[1] * C_T_G(c, t)[1] + C_VOF_G(c, tp)[2] * C_T_G(c, t)[2]);

                #endif

                #if RP_2D

                C_UDMI(c, t, 0) = (C_VOF_G(c, tp)[0] * C_T_G(c, t)[0] + C_VOF_G(c, tp)[1] * C_T_G(c, t)[1]);

                #endif

            }

            end_c_loop(c, t)

        }

    }

    Message(“Freeing storage variables…\n”);

    Free_Storage_Vars(pDomain, SV_VOF_RG, SV_VOF_G, SV_NULL);

    Free_Storage_Vars(domain, SV_T_G, SV_NULL);

    Message(“Exiting DEFINE_ADJUST(area_density)…\n”);

}

in this function error occurs in

 Scalar_Reconstruction(pDomain, “vof”, SV_VOF, -1, SV_VOF_RG, NULL);

 Scalar_Derivatives(pDomain, “vof”, SV_VOF, -1, SV_VOF_G, SV_VOF_RG, Vof_Deriv_Accumulate);
I also tried by putting "pressure-based" but result is same. I tried to search it but i didn't find an answer.
When I remove these two scalars then there is no error in calculation but my results are coming not accurate. Can you help me to solve this

 

[Rob]

I'm not going to debug UDFs, as I'm neither permitted to (the rules) or know enough to (I have colleagues who code). However from a quick look you have tp, pt and t in various commands for the threads. Be VERY careful with some of these as tp is also used in the DPM model so may be a reserved term. Similarly you're using SV_..... macros, these need to be used carefully and may not be fully documented: as such they may not work in all scenarios.