How can I locate cells with low temperature? |
Following is the procedure to locate the cells with low temperature:
1)Read the case and data in which temperature limitation messages were coming. 2)Open the Adapt -> Iso Value panel 3)Select... |
What is Angular Discretization? Should I change it? |
It defines the number of control angles that are used to discretize each octant of the angular space. By default, the number of Theta Divisions and the number of Phi Divisions are both set to 2.... |
How do I read in a transient time temperature data to be used as inlet boundary condition? |
Create a text file with your data in the following format:
sampletabprofile 2 3 0 time temperature 1 10 2 20 3 30 sampletabprofile is the name #2 is for number of variables, #3 is for how many... |
What is Partial Enclosure Temperature on radiation panel? Do I need to change it? |
The Partial Enclosure Temperature is the temperature for radiation purposes of the boundaries not participating in the S2S radiation exchange. You do not need to change it because the default is... |
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:
In the Material Properties panel, set the density to be "ideal gas". Initialize the flow domain to near stagnation properties. In... |
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
Injection *Ilist = Get_dpm_injections(); You... |
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... |
solidification/Melting for pure component in V12.0.16 |
For Pure component solidification ( when Tl = Ts) the temperature and liquid fraction field is not correct.
This is a bug and is fixed in R12.1. The workaround is: 1. Provide slightly higher... |
How to create mass weighted average function by UDF on a surface? (not on a zone or thread) |
The following UDF allows you to compute mass weighted average of temperature based on any surface. You just have to provide surface ID. #include "udf.h" #include "surf.h" #include... |
POLYFLOW - How to plot a membrane (thermoforming) in ANSYS? |
Let us consider that a thermoforming simulation with POLYFLOW is completed. Output files are created for ANSYS Mechanical. How can one display the thermoformed object in ANSYS, including the... |
Workaround for Airpak cases involving solar load and DO radiation |
In Airpak, if we have solar radiation turned on, a transparent surface defined and the DO radiation model turned on for radiation calculations, unrealistic results are obtained. Temperature values... |
How does FLUENT calculate the enthalpies in reacting flows reported in the Report/Fluxes panel? |
How does FLUENT calculate the enthalpies reported in the Report/Fluxes panel?
1. For non-reacting flows, enthalpy calculation at any boundary is straight forward. Assuming constant cp, enthalpy... |
FLUENT6 - freezing the values of selected flow variables in selected cell zones |
There are times when it is desirable to freeze the solution for one of the variables in one or more cell zones. FLUENT provides a method for fixing the values in a cell zone if constant values are... |
FLUENT V6 - User-defined Function (UDF) to export Discrete Phase Model (DPM) particle properties to a file |
Although FLUENT provides a method of sampling DPM particles as they pass through planes and outlets, there is no simple way to export particle data for all of the particles in the domain. This is... |
FLUENT V6 - Procedure for setting up a partially-premixed combustion simulation using materials from CHEMKIN database |
Procedure to create a partially-premixed combustion case using materials from CHEMKIN database in FLUENT 6.3.17
1. Copy the thermo.db file located in... |
POLYFLOW - What value could be assigned to a heat transfer coefficient along a boundary? |
Non-isothermal simulations require imposing boundary conditions for the energy equation. Imposed temperatures as well as vanishing fluxes are easy to set. Sometimes however, a heat transfer... |
total NOx is less than Thermal NOx alone in FLUENT |
In some cases, why total NOx is lower than Thermal NOx only.
This is due to reduction reactions in prompt and fuel NO models. Therefore, net NO formation = overall NO formation - overall NO... |
AIRPAK - How to properly account for sensible heat and latent heat for indoor ventilation simulation |
Engineers are given information on the total cooling load of a space due to occupants that identifies both the sensible heat (SH) and latent heat (LH) components. what values should be entered as... |
FLUENT 6 - On the fly monitoring of maximum/minimum values of any variable in the domain |
Many times while running cases, it is required to monitor the maximum/minimum values of some variables like temperature, pressure, turbulence quantities etc. in the domain. These values cannot be... |
UDF for profile transfer (velocity, temperature, species.......etc) across a non-conformal interface which seprates volumes of different mesh size |
This is a problem which we often come across. Many times it happens that in some volumes we need finer mesh resolution while on others we need very coarse mesh. This leads to non-conformal mesh... |
How to interpret radiation flux report at external semi-transparent boundary of solid cell zone in Fluent 6.1 |
In applications which involve modeling solar radiation through windows using the non-gray DO model it is often desirable to model the window as a solid cell zone that participates in radiation.... |
Helping energy convergence with conjugate heat transfer and tet mesh |
For conjugate heat transfer problems with tetrahedral mesh, and especially with widely varying thermal conductivities, sometimes the energy equation
is difficult to converge at the start of the... |
Some times I see negative Heat flux at inlet and positive heat flux at outlet. Is it possible to have such results ? |
Yes, it is possible. This is because in the calculation of heat flux at flow boundaries, heat of formation is also included. Following is the explanation of the same :
The energy flux out of a... |
UDF to modify under-relaxation factor |
Client wants to set URF for temperature at iteration 0 to 0.9 and gradually increase it to 1.0 over a set number of iterations.
The following UDF does this. You must set function hooks for the... |
How to compute view factors between two surfaces? |
Given a geometry, how do I compute the view factors without using DO model?
For a given geometry, suppose, we have Surfaces 1, 2, ... We want the view factor between 1 and 2: F12. * Turn on... |