KR18: What is a journal file in FLUENT? |
A journal file is a series of TUI commands stored in a text file. The file can be written in a text editor with text commands and scheme commands or generated by FLUENT as a transcript of the... |
KR19: What are pressure-based solver vs. density-based solver in FLUENT? |
Pressure-based algorithm solves the pressure equation to conserve mass, and can be used in any flow simulation except with the following features: real gas models, non-reflecting boundary... |
KR20: Can you give me some recommendations on how I can effectively model transient free surface flows such as in ink jets with FLUENT? |
Use the Volume of Fluid (VOF) model in FLUENT to model free surface flows. Some recommendations for the mesh and solver settings are given below:<br><br>Although the VOF model will... |
KR21: How to verify if the injected spray-mass is correct or not in FLUENT? |
In many spray related applications, it is important to ensure if the sprayed mass is consistent with that of the test conditions. Many of these applications involve evaporating sprays. In SCR... |
KR22: How to Remove a Particle from Domain using UDF? |
While writing a DPM specific UDF, sometimes it is required to terminate (remove) particles that do not meet a particular condition. In some cases, you may want to remove all particles whose... |
KR23: How to partition the grid for parallel DPM Solver? |
There are two options in DPM Parallel, Shared Memory and Message Passing.<br><br>1) Shared Memory: The Shared Memory option is based on a shared memory model. When using the Shared... |
KR24: How to run a batch job using a journal file in FLUENT? |
A simple journal file (e.g. batch.jou) can be created using any text editor with the following lines:<br><br>;; Read case<br>rc internal_wall_twod.cas<br>;;... |
KR25: How to modify DPM injection mass flow using UDF? |
If you want to modify injection inputs using UDF, you will require the following DPM macro<br><br>DEFINE_DPM_INJECTION_INIT<br><br>This macro provides access to particle... |
KR26: Is it possible to run multiple jobs sequentially in FLUENT? |
Yes, you need to create a journal file similar to:<br>;; Read first case<br>read-case-data case1.cas<br>;; Iterate<br>solve it 10<br><br>write-case-data... |
KR27: How to loop over all the DPM injections (and particles) using UDF? |
To loop over all the injections, you first need to get a list of all the injections you have defined. This can be done using the following command<br><br>Injection *Ilist =... |
KR28: What is the difference between particle parcel and stream? |
In Unsteady DPM: It is very expensive to track each individual particle in a particle flow system. Instead of tracking each particle, FLUENT tracks Parcel. Parcel contains particles with same... |
KR29: How do I set up a compressible flow in the segregated solver for a stable solution process? |
There are several steps which will work under most circumstances:<br><br>In the Material Properties panel, set the density to be "ideal gas".<br><br>¿... |
KR30: How can I improve the convergence of calculations involving the use of porous media with a large pressure drop? |
In calculations involving the use of porous media, the pressure tends to change rapidly in and around the porous regions of your model. Attempting to resolve these large pressure gradients through... |
KR31: How do I interpolate existing FLUENT solution to a new mesh? |
1.Write an interpolation file of required field data on required cell zones for the solution data to be interpolated onto the new grid by:<br>File ---> Interpolate / Write... |
KR32: How to get default setup when launching a new fluent session without storing it in the case file? |
This can be done in the start-up ".fluent" configuration file which must be located in the home directory. For instance, if we need to assign at the start-up level the... |
KR33: For a MDM simulation, when creating initial mesh, do we include rigid body as volume zone or only the wall zones composing that volume? |
This is very much problem dependent. If the specific boundary conditions are known and flow properties inside the volume (e.g temperature/ stresses) are not important to the problem, then only... |
KR34: How do I control batch runs in FLUENT, i.e., interrupt them, or obtain intermediate case and data files without terminating them? |
The owner of the FLUENT process(es) can create a "kill-file" called<br><br> /tmp/exit-fluent<br><br>Upon completion of the NEXT iteration, FLUENT will... |
KR35: How do I set a command monitor through a text interface (TUI) command (useful for batch runs)? |
For example, use the Scheme command:<br><br>(rpsetvar 'monitor/commands '((com-name 20 #f "/display/hardcopy<br>... |
KR36: In the 6 DOF solver, will the dynamic mesh solution be using the density of solid, specified through material panel, to calculate the mass of the moving object and so the gravity force? |
The properties of the object for 6 D.O.F solver has to be specified explicitly with a UDF and not in the materials panel.<br><br>Use the macro DEFINE_SDOF_PROPERTIES to define mass and... |
KR37: How does the dynamic mesh handle scenario of solid object hitting the wall? |
Consider a solid box falling in water under effect of gravity for a dynamic 6 DOF simulation. If the solid density is higher than the liquid, the rigid box would sink into the liquid and... |
KR38: As a beginner, which radiation model would you recommend to use for what? |
S2S for radiative exchange between surfaces. If the medium participates in the radiation exchange, DO and DTRM can be used for all range of optical thicknesses. P1 is preferred for optical... |
KR39: What does tolerance on DTRM panel mean? |
The Tolerance parameter (0.001 by default) determines when the radiation intensity update is converged. It is defined as the maximum normalized change in the surface intensity from one DTRM sweep... |
KR40: How can I write case and data file without stopping the FLUENT run on Windows? |
I have started Fluent run with higher reporting interval and now I want to stop and write the case and data file.<br>There is an option in Fluent to write the case or data file even without... |
KR41: What does tolerance on S2S panel refer to? |
The Tolerance parameter (0.001 by default) determines when the radiosity update is converged. It is defined as the maximum normalized change in the radiosity from one S2S sweep to the next. |
KR42: What does S2S Sweeps refer to? |
You can control the maximum number of sweeps of radiation calculation per global iteration by changing the Number of S2S Sweeps. The default setting of 1 sweep implies that the radiosity will be... |