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Questions related to FLUENT
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For comparison study of experiment and numerical work, I have to create rough surface structure modeling. which implies my numerical model would be more accurate equal to the experimental work.
But I don't know how to create a rough surface on all the inner walls of the channels (see the attachment).
Approximate dimension details:
Channel width 0.5 mm and height: 1mm
Ra: 300 micrometer
Please help me with how to do that.
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Son ich ngo Yes definitely I will try this way also.
虞军辉 junhui yu here I've attached the screenshot, in laminar flow conditions I can't be able to add roughness value on boundary conditions.
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Hi dears
I want to simulate vibrating system with 2 phase fluids. How can I set the velocity in fluent?
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You may need expressions or UDF features in fluent to do this.
You can find the introduction to "expression" in the following g link.
You can find an introduction to UDF in the following link:
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Currently, I have completed my research study for CFD simulations, using Ansys Fluent as a student in Anglia Ruskin. Now, I cannot use any Ansys licence through university as I am not anymore a student.
So, I am looking for a good software CFD free of charge to be used for research without restrictions (Student or Educator Version). Ansys Fluent Student version has some limitations and cannot be used for research with refined mesh study. I am looking for alternatives, finding a free good CFD software.
I have looked on Autodesk website and found the Autodesk CFD Ultimate as a Student or Educator version, it is free of charge.
This software can be used for computational fluid dynamics simulations and solid body motion analysis.
However, I have not used this software for CFD and I do not know if there are any limitations.
Is anyone using this software for CFD simulation please let me know if this software has any limitations?
Any idea, suggestion or thought, I would much appreciate.
Thank you.
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The CFD simulations is importance to both students and educators. This is because it is able to open the inside and view the behaviours.
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I am working on droplet microfluidics, where multifluid has been taken as discrete phase and 1 continuous phase. I am working on Ansys Fluent, can any1 help me regarding that how to calculate the interfacial tension between two fluids.
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The VOF model is the model for multi fluid simulation. This model calculates the surface tension at the interface of the two phases. If you open Ansys Fluent, you will see that when setting the surface tension, it says "Phase-Pairs".
You wrote yourself what you need to model : "...where multifluid has been taken as discrete phase and 1 continuous phase..".
Such a case should be modeled using the VOF model. In Ansys Fluent you need to create a mixture where Primiry Phase will be your continuous fluid; Secondary Phase will be discrete phase. You set the surface tension coefficient by the discrete phase because it is discrete and therefore has a free form. The continuous phase has no surface tension coefficient, because it is solid and has no free form.
VOF model is your case ("...where multifluid has been taken as discrete phase and 1 continuous phase...")
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I am a beginner in Ansys and passed CornellX ANSYS course, but modeling a complicated meshing and geometry of the centrifugal pump need support or assistant from who success to accomplish this simulation correctly before.
Any kind of support will be highly appreciated to allow me start my research of master degree about centrifugal pump operation at off design operating conditions.
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I was reading a paper "Experimental modeling of a curved Ranque–Hilsch vortex tube refrigerator" and trying to validate the vortex tubes using ANSYS FLUENT. All the data points are close to the experimental results except cold mass fraction greater than 0.7. The problem I am facing is that the hot exit temperature becomes elevated instead of decreasing at 0.7 cold mass fraction at 3 bar inlet pressure. Why it is decreasing? I read other papers especially the vortex tube paper by Skye et al, their hot exit temperature is increasing at the higher cold mass fraction. Reference: https://doi.org/10.1016/j.ijrefrig.2011.02.013
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Another explanation is that you may have set the wall in Fluent as adiabatic. However, in the experiment, it is often not the case. As the mass flow rate through the hot outlet decrease, the hot outlet temperature may become more sensitive to heat loss and the hot outlet temperature drop in the experiment.
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I'm currently using fluent simulating the cold flow of a supersonic combustion chamber with using hydrogen as fuel. But I can't make it to start the first iteration. Can someone give me some advice?
These are the error respond from fluent
WARNING: Invalid cp (0.000000e+00 J/kgK) for oxygen at temperature -1.#IND00 K
reversed flow in 500 faces on pressure-outlet 8.
Stabilizing nut to enhance linear solver robustness.
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
WARNING: Invalid cp (0.000000e+00 J/kgK) for hydrogen-air at temperature -1.#IND00 K
Divergence detected in AMG solver: nut
Error at host: floating point exception
Error at Node 0: floating point exception
Error at Node 1: floating point exception
Error at Node 2: floating point exception
Error at Node 3: floating point exception
Error at Node 4: floating point exception
Error at Node 5: floating point exception
Error at Node 6: floating point exception
Error at Node 7: floating point exception
Error at Node 8: floating point exception
Error at Node 9: floating point exception
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Are you applying compressed ideal gas law? Also, set operating pressure zero and operating density also zero. Don't use outflow boundary condition.
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Dear all
Im working on cfd simulation of solar stillin my fonal year project but we face a error while simulating it using ansys. I used vof method with three phases (air, water, vapour)
THE ERROR IS
"LATENT HEAT CANNOT BE LESS THAN ZERO "
WHAT DOES THAT MEAN??
I changed sse of water to zero and sse of vapour as given in this website
Standard State enthalpy -- CFD Online Discussion Forums (cfd-online.com)
but still same error please help me asap
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Did you check the units of the represented latent heat in the software, that could be a reason for an error in your value.
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Hi all, I'm kind of stuck in my validation for Al2O3 water nanofluid. the correlations for Nusselt number from Pak and Choi; Xuan and Li and Maiga seem a bit strange for me to compare my numerical results. I have got the results under constant temperature where the average increment for heat transfer coefficient was around 25%. But from the literature it should be 5-10%. I'm not sure whether my numerical results are right?
I think Eulerian two-phase model in fluent over predicts the outlet temperature of pipe.
and another doubt: Is constant heat flux boundary condition not compatible with mixture model in fluent?
Any suggestions would be really helpful.
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In simple terms for a constant property system the heat transfer coefficient is a function of gas velocity. For flow inside tubes the relationship is h = k1 x V^.8, for flow outside of tubes it is h = k2 x v^.5: this is, of course, a simplification but a reasonable approximation. k1 and k2 are constants for a given system v is the fluid velocity. Thus, a doubling of Re (or velocity) for flow outside a tube gives an increase of h of about 40%, or, inside of about 80%.
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Dear All,
Good time,
In Ansys Fluent, I am using 2D non-premixed turbulent combustion model, I am using WSGG model to find the influence of radiation on participating species, my query is,
After thousand of iteration step, contour for temperature, is convincing and giving a good flame structure but incase of CO2 and H2O, what I see is, from flame till outlet the whole combustor is filled of CO2 or H2O, what parameter should I change/consider in my fluent simulation to make it better?
For your convenience I am attaching contour of both T and CO2.
TIA.
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The temperature profile indicates a diffusion flame, but the concentration profile seems like a pre-mixed flame where all the CO2 forms at the flame-front. To go further needs geometrical details of gas and air inlets and the enclosure as these determine the flame temperature and shape. However, my impression is that there is something wrong with the mathematical model used.
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I know this is basic question. In Eulerian model the velocities and temperatures are different for continuous and discrete phases.
In this problem:
  • For single phase (1% Al2O3 - water nanofluid)
The thermo-physical properties are calculated using nanofluid correlations. from that the velocity is calculated for specific Reynolds number (20,000); let's consider
1% Al2O3 nanofluid velocity (V=2.1425 m/s) (T_inlet= 293K)
  • For Eulerian model (1% Al2O3 - water nanofluid) (Re =20,000)
water inlet velocity: V=2.1425 m/s ; (T_inlet= 293K)
Al2O3 Inlet velocity V=2.1425 m/s; (T_inlet= 293K)
Should i have to use same velocity and temperatures for Re=20,000 for Eulerian model. Any suggestions would be really appreciated?
Thank you
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This is a turbulent two-phase dispersed flow. I think that one may consider that continuous and discrete phases would have the same instantaneous velocities in turbulent flow if the dispersed phase has a size smaller enough in comparison to Kolmogorov scales in the turbulent continuous phase. As for temperature, and the same way one should compare the time scales related to heat transfer to the Kolmogorov time scale. However, if the flow is isotherm, which seems the case, both phases will have the same constant temperature
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In am using a UDF for heat flux that is dependent on temperature. If I am using constant temperature it is giving results. But using temperature function (F_T(f,t)) in code, fluent is crashing withot any error while initiation. I am attaching my code.
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Heat flux will be applied at the walls and you may be required to use near-wall cell thread (i.e. t0) instead of cell interior thread (i.e. in this case "thread").
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Hi everyone,
I would be very grateful if someone could help me in calculating the local and average Nusselt number in a rectangular microchannel, as the default magnitude of the Nusselt number in fluent is incorrect. I know the Nusselt number equation (Nu = h*Dh/kf), but I want the procedures used to calculate it in FLUENT.
With my best wishes.
Dr. Ahmed F. Al-Neama
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You need to draw like 5-6 planes along the cross-section, and compute the following:
Local Nusselt number = [q˙/(Tw−Tf)]*Dh/k
Where:
q˙= local heat flux [W/m2].
Tw= local wall temperature (or maximum temperature at this point) [K].
Tf = local fluid temperature (or the average temperature) [K].
Dh = Hydraulic diameter [m].
k = thermal conductivity [W /( m⋅K)].
For, average Nu, just do the integration.
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hello,
I am studying the vortex-induced vibration on an oscillating cylinder to be only translated in the y-direction when it is encountered with a flow,
I have gotten this code from the forums but I get this error
Error: C:/Users/lenovo/AppData/Local/Temp/CODE 5.txt.31400.9.c: line 3: parse error
the code :
#include "udf.h"
static real v_prev = 0.0;
}
DEFINE_CG_MOTION(osc,dt,vel,omega,time,dtime)
{
Thread *t;
Domain *d = Get_Domain(1);
real x_cg[3], force[3], moment[3];
real accl, dv;
real mass = 0.2;
real wn = 12.0;
real k= mass * wn*wn;
real c = 2*mass*wn*0.00;
int i;
}
NV_S(vel, =, 0.0);
NV_S(omega, =, 0.0);
t = DT_THREAD(dt);
for(i=0;i<3;i++)
x_cg[i]=DT_CG(dt)[i];
Compute_Force_And_Moment(d, t, x_cg, force, moment, TRUE);
force[1] += -k*x_cg[1] - c*vel[1];
accl = force[1]/mass;
dv = accl*dtime;
v_prev+=dv;
vel[1] = v_prev;
printf("Computed force: %g \n", force[1]);
printf("Velocity: %g\n", vel[1]);
}
DEFINE_CG_MOTION(osc_inert,dt,vel,omega,time,dtime )
{
vel[0] = 0.0;
vel[1] = v_prev;
}
so, if anyone could help or have a better code to use this udf for my graduation project I'll be very thankful
thank you in advance.
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Hello. In my opinion, you are using a strange method to solve your problem. Why do you use programming? Why do you use such a difficult method? As I understand it, you just need to perform an FSI analysis. In the Ansys Fluent program, FSI analysis can be performed inside it. Check out the tutorials in chapters 24 and 25 inside the archive I attached to this post. In these chapters, step-by-step examples of solving one-way and two-way FSI problems are described. The attached archive also contains the source files for performing step-by-step examples, so you can repeat them.
In addition to this method, you can connect different systems inside the Ansys Workbench program. For example, you can connect a CFX module or a Fluent module with a Static Structual module or Transient Structural module to get a one-way FSI. To perform two-way FSI inside the Ansys Workbench program, in addition to linking CFX or Fluent modules with Structual modules, all of them will need to be additionally linked to the System Coupling system.
But in all these ways I have not seen anything programmed.
In your case, it seems to me that the internal capabilities of the Ansys Fluent program will be enough.Everything is done there without programming, there are already all the necessary functions inside Ansys Fluent. You can even watch the von Mises stress.
On the other hand, if the internal capabilities of Fluent in this regard are not enough for you, you can always link specialized strength modules and gas dynamic modules using the System Coupling system.
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I simulate simple model in fluent ansys the 3D-model called vortex tube , but meet me some problems and i don't know why ..?
1-I used structure mesh give me orthogonal quality min: 2.88 E-4 max: 1 with Aspect ratio min 1.0561 and max 11834 , This values of mesh Acceptable or not acceptable .. ?
2-when run this model fluent showed some note such as turbulent viscosity limited 10 E-05 and temperature limited 10 E-10
3- occurring reversed flow
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Check your Boundary Conditions, especially pressure outlet conditions.
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Hi
I am trying to simulate evaporation of gas R134a using Lee model in VOF, the problem is during the boiling process the bubble forms but the temperature of the liquid is increasing more than the saturation temperature though it should be constant during the boiling process. So why this happens is there something need to be defined.
Thanks
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Hey Mohammad, check this out , it should help you with the simulation.
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Hi all,
I am going to use either Ansys CFX or Ansys Fluent solver to simulate flow past a semi-submerged rectangular cylinder, as shown in Fig. 1. The main goal here is to achieve an accurate prediction of pressure distribution over the cylinder, which seems to be particularly reliant on the capability of the CFD model to predict the separation and the reattachment of the flow correctly. I would appreciate any tips regarding the following questions.
Q1. How important is the choice of the turbulence model? Which models are superior? Could the flow be modelled as being laminar at all?
Q2. How important is the approach to the free surface? Could the free surface be modelled as a free-slip wall to reduce computational costs? Is it necessary to precisely track the free surface using the VOF model for this study?
Q3. What are the most appropriate boundary conditions for the simulation?
Q4. Which is more suitable for this problem? CFX or Fluent?
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If the size t is less than 8-12 distances to the bottom surface, the drag force will be determined, among other things, by the added masses of the liquid reflected from the bottom surface. If this is not important, then in the model you need to specify a distance of more than 12.
The number of wall layers is enough 5.
From above on a free surface, the wind has a speed and direction?
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I have just simulated a steady state 2D methane-air combustion case with species transport model and eddy-dissipation turbulence-reaction model with the use of Fluent code. The solution is converged and the results match very well with the experimental data. For some purpose, I need to show manually that the transport equation for N2 equals zero since it is an inert gas and does not participate in the reactions. I got all the necessary flow field variables from the CFD solution such as density, axial and radial velocity, and N2 mass fraction. For some points in the flow field, I am trying to solve manually the same turbulent transport equation for N2, which Fluent code solves, with the central finite difference method using the flow field variables from CFD. My step size in the flow field is 0.0002m for the finite difference method. However, my finite difference method results are far from 0, which means as if N2 gas participates in the reactions. I find the reaction rate term (Rn2) for N2 around 5 kg/m3.s, as it must be very close to 0 for the numerical solution.
Where do you think I am wrong or missing something? Thank you very much.
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You cannot use an arbitrary discretization! You have to reply exactly the same formula used by Fluent.
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Hello, Dear All
Has anyone done numerical simulation using ANSYS FLUENT software for non-Newtonian flows such as Bingham for example "drilling fluid" that can help me in case?
My Question: What is the range of Herschel-Bulkley Parameters such as: Consistency index (k), Power law index (n), Yield stress and Critical shear rate in these fluids? If you know the reference in this case to help me, Please let me know?
Thank you for your consideration
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Hi,
Could you please identify the type of help. Are you struggling in something , please clarify
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I would like to simulate temperature developments and shear rates of a plastic which is extruded through a nozzle.
In addition, a rod rotates in the nozzle to apply more shear (and heat energy) and to generate a mixture.
Important are:
- Material models: viscoelasticity, structurally viscous material, thermoelasticity
- To be able to model rotation well
- Temperature developments
- (mixing)
Ansys Polyflow:
- Specialised on extrusions
- Viscoelasticity
- Non Newtonian viscosity
- Rotation can be modelled well (according to a literature source)
- Unfortunately, thermoelasticity cannot be modelled (and I do not know if this can be modelled by myself).
Is Ansys Fluent the better choice, especially because of the thermoelasticity and the wider range of functions?
I hope you understand my case.
Thank you!
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I would try Polyflow first.
Maybe you could consider the temperature dependance of the viscosity by implementing a temperature dependance yourself.
You should consider what is more important/relevant for your problem: viscoelasticity (then Polyflow) or thermoelasticity (then Fluent).
Good luck and success with your challenging task !
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Currently I am working on Performance analysis of savonius Turbine.For which I am using dynamic mesh method in ansys fluent.I have done simulations for free air velocity ranging from 3-9 m/sec, and found out the moment coefficient, RPM of the rotor,
The problem I am facing with the analysis are as follows -
  1. I am getting moment coefficient an moment values that are cyclic in nature which is correct as per the literature and behavior of savonius turbine ,but the problem is both moment and and moment coefficient are varying between two equal +ve and -ve values (for eg +0.5 to -0.5) which is causing the average moment to be 0 and hence I am getting very low power.
  2. The rpm value is reaching to a constant point which is also very low as compared to the experimental results available.
Can anybody give feedback why I am getting such results and what I did wrong in my analysis.
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Check your mesh especially at the boundary layer. Choose appropriate turbulence model that can resolve your boundary layer accurately. You can check more 10.1016/j.jweia.2022.104920
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I am simulating injection of water droplets in a supersaturated water vapor filled enclosure using fluent. I have used discrete phase modeling for the injection part. The real gas option is enabled and I am able to observe the liquid droplets cooling the continuous phase and evaporating/boiling. Therefore, the temperature and pressure is dropping in the closed volume as expected. However, it drops down so much so that the vapor (continuous phase) is below the saturation point.
It is expected that the vapor will convert to water liquid at this point but I couldn't find any option to include evaporation-condensation model for the continuous phase. Is it possible to use both DPM and multiphase flow model (like Eulerian model) so that the phase change in the continuous phase can be modeled?
Thanks.
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Thanks for the response Anit. It is possible in fluent as well but my case is injections (water droplets) which is why DPM is better than multiphase models like VOF. however, I am facing a challenge using both multiphase (for continuous phase) and DPM (for discrete phase) together.
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Dear all,
Does anyone know how to edit the geometry of the dambreak.msh file provided by ANSYS Fluent?
Or does anybody have a project file for the dambreak case without the statement that the mesh file is imported and therefore not editable.
We want to add a geometry in the downstream region as an obstruction.
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Dear Momen,
Thank you very much, I appreciate it!
When can I call you, what do you prefer?
Regards, Rob
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Hello! I am trying to simulate a trombe wall with semicircural fins with phase change materials in Ansys Fluent. I am using turbulance viscocity model and direct ordinates model for radiation. Im using bousinesq model for the air, with destiny 1.225 kg/m^3, ( to make possible the air movement due to different temperature), in the image you can see the else properties of the air that im using. I also upload the boundery condition for the glass wall, and the radiation and mixed conditions that im using. The perimeter of the room are adiabatic walls, the else walls are coupled. I upload the mesh file to see the geometry and the named selection. Im phasing problem with the residuals of condinious equatin (i have aploded the image too), im using time step 1s and max iterations/per time step 20(ive tried to change them but the problem didnt fix. If i try the adaptive type in calculation the time step is 1e-06. I dont how to fix it. Can anyone help me?
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Hi, I am also working in the same area have you got the solution about this. I need some help with this.
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I solved a case with Ansys Fluent, but when I load the result file and try to make a contour, many variables, like Particle Mass Concentration are missing, which is exactly what I need. When I use CFD-Post, it says "Error: Variable does not exist". What could the problem be? Thanks in advance!
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Hi! You can only export your desired quantities to CFD-Post if you save your data file in the legacy format.
Please go to File>Preferences>General. Change the 'Default Format for I/O' from 'CFF' to 'legacy'. This will let you access the 'Data File Quantities' option and help you to export your desired quantities to CFD-Post.
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Hi all. I need to model blood clots inside stenosed arteries. I found a similar paper that simulated blood clotting using lattice-boltzmann method. The authors injected a 'passive scalar' at every lattice node during each time step. Convection-diffusion eqn was solved for this massless scalar. If, at any lattice point, the concentration of this scalar exceeded a threshold, then that lattice point was changed from a "fluid node" to an "obstacle node" & solid surface Boundary cond. was applied. Thereby mimicking a solid clot. I'm curious if it is possible to achieve something like this in ANSYS FLUENT (possibly via a UDF). Thank you.
Original paper: Concurrent Numerical Simulation of Flow and Blood Clotting using the Lattice Boltzmann Technique
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Prateek Gupta , to solidify, while entering density; enter density value same for irrespective of temperature which represents that density does not change with temp. so it get solidified.
even your suggested logic is also correct.
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Dear all,
I have tried to simulate the phase change from a solid to liquid in Ansys FLUENT by providing heat flux at a wall [Using the Solidification and Melting model]. I got the results [video attached: 0-1 min temp plot, after 1 min liquid phase plot]; the heat flux creates temperature change over time, leading to a change in phase based on the solidus and liquidus temperatures.
But, the fluid flow doesn't occur, i.e., the flow equation is not solved. I want to simulate the flow of liquid PCM due to gravity. Is there any predefined option to perform that? or is any udf available? Kindly help me..
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Prince Abraham Turn on gravity option on, and use techplot soft for particle movement. that will give better result . or you can also go for rockey 2.0 software.
Find below article in which you can see flow,:
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Hi there,
I'm working 2D axisymmetrical pipe groove (CFD) model with constant wall temperature. During the hybrid initialization, I have a non-positive element error along with a floating point exception. I believe I'm missing something. Any suggestions would be really helpful?
Thank you
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i actually meant to say.. dont use hexa mesh.. i could not go back and correct it.. sorry about that..
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Hi, I have been trying to import the thermophysical properties of CO2 (for the supercritical region) to Fluent by using UDF (only for 80 bar). End of the analysis, the result is not correct. I think Fluent is pulling a Tref value which causes my enthalpy to go negative; therefore, the energy equation does not give accurate temperature results, so the result of thermophysical properties, which are functions of temperature, are wrong. I want to be grateful if you could share your recommendations, especially on the methods of correct calculation of enthalpy. My specific heat code is as follows:
#include "udf.h"
DEFINE_SPECIFIC_HEAT(supercritical_cp, T, Tref, h, yi)
{
real cp;
if (300. >= T)
{
cp = 2.256999118844760E-02 * pow(T, 4.) - 2.606618818487370E+01 * pow(T, 3.) + 1.129129898467780E+04 * pow(T, 2.) - 2.174235523392760E+06 * T + 1.570278261279480E+08;
}
if (306. >= T > 300.)
{
cp = 1.147018354719330E+01 * pow(T, 4.) - 1.385519872072390E+04 * pow(T, 3.) + 6.276090044658930E+06 * pow(T, 2.) - 1.263530241490370E+09 * T + 9.539285116131690E+10;
}
if (307.8 >= T > 306.)
{
cp = -1.611612838918710E+04 * pow(T, 4.) + 1.978085636985280E+07 * pow(T, 3.) - 9.104578256081260E+09 * pow(T, 2.) + 1.862478067464320E+12 * T - 1.428738938943020E+14;
}
if (310. >= T > 307.8)
{
cp = -1.576135476848110E+03 * pow(T, 4.) + 1.945866130859760E+06 * pow(T, 3.) - 9.008641337104630E+08 * pow(T, 2.) + 1.853611584329810E+11 * T - 1.430227164258690E+13;
}
if (320. >= T > 310.)
{
cp = 1.770529718817220E+00 * pow(T, 4.) - 2.242833202341920E+03 * pow(T, 3.) + 1.065432793165650E+06 * pow(T, 2.) - 2.249454519629040E+08 * T + 1.781003821884030E+10;
}
if (T > 320.)
{
cp = 2.086961941877520E-03 * pow(T, 4.) - 2.851496372954040E+00 * pow(T, 3.) + 1.461548345109060E+03 * pow(T, 2.) - 3.330816449664890E+05 * T + 2.848088978782360E+07;
}
*h = cp*(T-Tref);
return cp;
}
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Answer
I've looked at the polynomials that you have noted: none of them make sense, whether using actual temperatures or reduced temperatures.
I suggest going back to the original data and making your own, (lower order) curve fit using Excel.
One further comment, you would be mis-calculating enthalpy if you used your last equation as it assumes a constant specific heat over the temperature range: the correct form is to integrate Cp.dT over the range, I would integrate the secific heat equation (if it was correct).
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Hello,
I am dealing with error during lounching 2 Way FSI in ANSYS Workbench. Setup of the Fluent is ok (stand alone I am receiving expected results) and FEM uses Transient Structural.
Once I run the coupling I observe this error:
"Update failed for the Simulation compoment in System Coupling. The coupling service failed to start."
Please is here anyone who dealed with this error and was able to solve it?
Thank very much for your time.
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Thanks very much for your help!!!
Actually, I have checked my model several times, and still observed this error every times.
Finally, i used higher order version of workbench to calculate my model. I don't understand why, but it worked.
Thank you for your time.
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Hi, I am planning to work on a project to couple ANSYS and Python to automate the Design Exploration task. I am also thinking to use a GA to optimize the geometry. Outline as follows: 1.Parametric model in ANSYS Spaceclaim/DM 2.Model is automatically meshed 3.It is then fed into Fluent to obtain the results which are written to an output file. (Batch mode) 4.The python code reads the output from the file and calculates fitness. 5.Does Crossover mutation etc. 6.Writes the new parameters to an input file. 7.Which is then read by Ansys, steps 1-6 are repeated until convergence. Please note the geometry is modified in each generation of GA. Thanks in advance
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I am using PyFluent. Found it very useful.
Pasting the documentation link here : https://fluent.docs.pyansys.com/user_guide/index.html
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I am working on oscillating blade. i want to calculate phase average of flow variables. there is time statics option in the fluent and i think it calculates time average only. for phase averaging do i need to write a UDF? or there is some way i can find in the fluent itself.
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@ravi kumar
Were you able to calculate it in fluent?
Or you write a udf for that.
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Hello, I have tried correcting 2d aerofoil experimental CD and CL values for 3d effects by considering effective aspect ratio and delta alpha but, was unable to get the correct values. can someone help out how to correct them properly by giving an example?
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First return question : How do you get 2D experimental lift and drag coefficients? By force balances or pressure integration (lift) / wake integration (dag)? For the first: how do you eliminate the sides from the measurements? For the second: What is your spatial resolution by pressure probes? How big is the expected impact of the shear stresses?
Second retrun question: Did you already apply standard wind tunnel corrections like blockage, lift induction, wake blockage? If not yet, have a look to AGARDographs 336 and 109.
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I'm modelling a 3D, transient, 2-way FSI problem about deformation of a thin beam, with fixed support from one end and fully submerged in fluid. I need to apply force (or pressure) from one side of the beam to deform it however I wish to apply this force in the Fluent (not in the transient structural module) since the applied force is dependent to flow variables.
I tried to change the pressure on the surface using a simple udf as below:
#include "udf.h"
DEFINE_ADJUST(adjust_function,domain)
{
int surface_thread_id=27;
real press=5000.0;
face_t face;
Thread* thread;
thread = Lookup_Thread(domain,surface_thread_id);
begin_f_loop(face,thread)
{
F_P(face,thread)=press;
}
end_f_loop(face,thread)
}
There were no error at compiling, hooking udf or at running the simulation steps however pressure report or monitors showed no change in pressure on applied surface.
I would appreciate if anyone can help me on this issue.
Kind regards
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in two way FSI(FLUID-solid interaction) you should connect the transient structural and fluent system and in the transient structural environment, you should define this load on one side of the beam wall in relate to the time. in the following define this load as the pressure or force with constant values in time 0 in the table and for the other time define it as zero. when you coupled the transient structural and fluent in ANSYSWORK Bench environment in the wright way the problem will be solved.
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Hi, everyone! I am working on udf in Fluent recently. Ansys fluent 2021r2, vs 2019 professional. I faced this "Error at host: Error code:126" problem while loading the libudf. Does anyone know how to solve this problem? I deleted the folder "libudf" and recompile it, it doesnt works. Thanks a lot.
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Thanks for your answer.
It's a good approach for troubleshooting in the future.
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Respected all,
I am working on vertical axis water turbine and I want to rotate each blade individually about its centre of rotation. I have tried both the mesh motion and frame motion y giving the centre of rotation of each blade separately but none of them worked.
My supervisor said, I need to write a udf to rotate the domain but as per my thinking Ansys allows the simple rotation of a body relative to a domain. but in my case nothing seem to work.
Can anybody please help me in this ?
Thanking you in anticipation.
I have attached the picture of my problem as well.
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Yes, I think so ;-). Look at the conversation above.
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Streamline plots for Experimental data points and Ansys fluent data points are plotted in Tecplot 360.
While it is needed to compare the two plots it is observed that the axis labels in both plots are changed with units systems i.e ( mm and m )
Is there any options to make the unit’s systems in both the plots with the same units and labels?
Reference figures 1 and fig3 are attached for reference.
Also, the Experimental data set changed to m and plotted but the streamlined plots were found not to be fitted as expected.Reference fig 2. attached
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I can easily create the geometry and run this problem for you, but I wouldn't use Fluent. Why not use a free model with readily available source like John Burkardt's adaptation of Max Gunzburger's code published in, "Finite Element Methods for Viscous Incompressible Flows: A Guide to Theory, Practice, and Algorithms," Academic Press, 1989, ISBN: 0-12-307350-2? With the source code (do a Google search or get it off my website) you can output whatever you want in whatever form best suits your purpose. With Fluent, you're limited to the features and tools they provide. This book on CFD is free on Wednesday 8/31. https://read.amazon.com/kp/embed?asin=B082FPFN1M&preview=newtab&linkCode=kpe&ref_=cm_sw_r_kb_dp_62VKNBPAMRH9557B28JX
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I would like to do modeling and simulation of a salinity gradient solar pond in Ansys. Can anyone give me a guide on how to go about making udf for solar radiation and the other properties of this work ?
thanks.
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I have simulated a flow in Ansys FLUENT [Transient] and got around 3000 contours. Each contour for a timestep. I need to combine all those image frames to get an animated video.
I have tried to use online converters. But, since the number of frames is too much, uploading those to the cloud seems complicated. Could anyone please suggest any freeware to convert those image frames to video animation?
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Hi,
ffmpeg is your friend here. Googeling for 'ffmpeg image to video' or something like that produces a lot of material. This one, e.g., seems decent
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I want to calculate this integral in Fluent but I'm not sure that my strategy is correct or not!
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You should write a user defined function (UDF). You can get the values you need from fluent and calculate the integral.
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Hello,
I am trying to validate a paper on particle deposition in duct air flow. It said to inject 30000 spherical particle of 1 micron diameter in the domain from a surface.
How can I do this? There is no option of specific number of particle to inject.
Can I do this through mass flow rate option?
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Hello ..
Thanks for your reply. Which injection system should I use in Ansys?
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The mirror wall is used to reflect the solar radiation to another surface
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Dounia Chaatouf , apply reflectivity is it's not transparent or transmitivity.
even you can select material as glass from the material library.
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Hello,
im trying to simulate powder flowing through a nozzle carried with a gas.
The particles are small (30µm) and the volume fracion is low.
However its important for me to simulate the interaction, which is why i activated the DEM model, but no particles are injected or tracked.
Can someone tell me what might be the cause of that happening?
Thank you!
Kind regards
Marie
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Are you still working on this problem? I have done a lot of particle tracking (publications, models, examples) and even wrote a book on the subject. I may be able to help.
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Dear Altruists,
Greetings!
In my simulation case, liquid will be evaporated into vapor, and the phase change should be performed in the vacuum medium.
Anyone can explain how to define the vacuum fluid domain in ANSYS Fluent?
Thanks in advance.
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Define the continuum and the default fluid will be air, define its pressure to zero in atmospheric pressure
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I am trying to simulate condensation of saturated Water_Gas (vapor) at 240 C and 3.02MPa to Water_Liquid through a long tube at const. wall temperature of 100 C. The experimental pressure drop is 7.25KPa
In ANSYS Fluent multiphase (VoF/Mixture/Eulerian) model, what should I edit in case of standard state enthalpy and its reference temperature field for Water_Gas and Water_Liquid material properties? To some extent, I tried to refer the ANSYS Nucleate Boiling Tutorial case for my simulation setup. The tutorial document deals with water Boiling simulation. There, they have used 0 std. state enthalpy for liquid and 2.992325e+07 J/Kmol for gas both at 25 C reference temperature. This is done for mass transfer to occur from liquid to gas. My question is, for mass to transfer to occur from gas to liquid, should I set Water_gas enthalpy to be equal to 0 and use actual-default std. state enthalpy for Water_Liquid at 25 C? Thank You.
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Since you know the saturation temperature and pressure values, use the steam table and determine the standard state enthalpy of saturated liquid (h_f) and saturated vapor (h_g). Usually these values are in J/Kg unit, however FLUENT code uses unit in J/Kgmol. Here, the Kgmol is not equal to Kg*mol, rather, it is Kmol. Therefore, you should also be careful in converting it by multiplication of Molecular weight (Kg = Kmol*Mol.Weight).
Hope this is helpful.
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Hello,
I'm trying to write a UDF program. The UDF for specifying a transient temperature profile may have the DEFINE Macro as:
DEFINE_PROFILE (unsteady_temperature, thread, position).
How will the DEFINE Macro be written for two transient variables, temperature and pressure?
Thanks.
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You will have to write macros for the two variables separately and use them to specify input pressure and temperature profiles.
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Hello,
There are methods such as DPM, DEM, Eulerian, and MP-PIC to model fluidized beds with particles moving within the system. For systems with a very high number of particles moving within them, some of these models such as DEM are time-taking methods and in some other methods that have some simplifications, accuracy may not be enough. I was wondering what is an appropriate method for modeling fluidized beds with a very high number of particles moving within the system?
Thank you,
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I think that the simulation using mixture or eulerian model in Fluent will become an appropriate method for modeling fluidized beds with a very high number of particles moving within the system?
I wish you success.
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I am simulating the flow of super-critical CO2 over a circular cylinder in FLUENT. I am using NIST real gas model to calculate the thermo-physical properties of sCO2.
The residual for continuity, momentum and energy equations have been set to 10^-6, 10^-7 and 10^-8 respectively. Discretization for density, momentum and energy is set to second order accuracy.
Now I am having problem regarding the convergence of the continuity. Could anyone suggest me any solution strategies for this case ??
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In previous versions of FLUENT, such as FLUENT 15.0, iso-Value can be found under the menu of Adapt, which is a powerful tool when we want to adapt the mesh. However, in the newer versions, such as FLUENT 21.0, the iso-Value cannot be found under the same menu. Can anyone know how to adapt the mesh using iso-Values in FLUENT 21.0 as in older versions?
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You can change the mesh quality with console command
/define/ enable-mesh-morpher-optimizer?
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hi everyone, I'm trying to run a simple UDF on ansys fluent but when i compile it (build buttom) it shows me 1 error along with several warnings I will appreciate if anyone could give me a hand on this.
This is the complete output of the console along with the code
(console)
Copied D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent/D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\UDFex1.C to libudf\src
(system "copy "C:\PROGRA~1\ANSYSI~1\v212\fluent"\fluent21.2.0\src\udf\sconstruct.udf "libudf\win64\2d_host\SConstruct" ")
1 archivo(s) copiado(s).
(system "copy "C:\PROGRA~1\ANSYSI~1\v212\fluent"\fluent21.2.0\src\udf\scons_default.bat "libudf\win64\2d_host\scons_test.bat" ")
1 archivo(s) copiado(s).
Creating user_nt.udf file for 2d_host ...
(system "copy "C:\PROGRA~1\ANSYSI~1\v212\fluent"\fluent21.2.0\src\udf\makefile_nt.udf "libudf\win64\2d_host\makefile" ")
1 archivo(s) copiado(s).
(chdir "libudf")(chdir "win64\2d_host")
D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_host>rem
D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_host>rem Copyright 1987-2021 ANSYS, Inc. All Rights Reserved.
D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_host>rem
"cl.exe" no se reconoce como un comando interno o externo,
programa o archivo por lotes ejecutable.
"clang-cl" no se reconoce como un comando interno o externo,
programa o archivo por lotes ejecutable.
scons: Reading SConscript files ...
scons: warning: No version of Visual Studio compiler found - C/C++ compilers most likely not set correctly
File "D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_host\SConstruct", line 8, in <module>
scons: warning: No version of Visual Studio compiler found - C/C++ compilers most likely not set correctly
File "D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_host\SConstruct", line 18, in <module>
Compiler used is "C:\PROGRA~1\ANSYSI~1\v212\fluent"\ntbin\clang\bin\clang-cl
Linker used is "C:\PROGRA~1\ANSYSI~1\v212\fluent"\ntbin\clang\bin\lld-link
scons: warning: No version of Visual Studio compiler found - C/C++ compilers most likely not set correctly
File "D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_host\SConstruct", line 148, in <module>
Copy("D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_host\resolve.exe", "C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\win64\resolve.exe")
c_sources ['UDFex1.C', 'udf_names.c']
c_sources_ []
scons: done reading SConscript files.
scons: Building targets ...
"C:\PROGRA~1\ANSYSI~1\v212\fluent"\ntbin\clang\bin\clang-cl /c /DUDF_EXPORTING /DUDF_NT /DWIN64 /EHa /wd4224 -Wno-return-type -Wno-implicit-function-declaration -Wno-comment -Wno-incompatible-library-redeclaration -Wno-reserved-user-defined-literal /clang:-std=c99 -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\win64\2d_host -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\main -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\addon-wrapper -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\io -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\species -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\pbns -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\numerics -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\sphysics -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\storage -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\mphase -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\bc -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\models -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\material -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\amg -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\util -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\mesh -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\udf -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\ht -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\dx -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\turbulence -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\acoustics -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\parallel -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\etc -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\ue -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\dpm -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\dbns -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\cortex\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\client\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\tgrid\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\PRIME\tgrid\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\multiport\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\multiport\mpi_wrapper\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\include -I "D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_host" -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\MSVC\14.10.25017\include -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\x64\lib\clang\10.0.0\include -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\10\Include\10.0.18362.0\shared -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\10\Include\10.0.18362.0\ucrt -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\10\Include\10.0.18362.0\um udf_names.c
In file included from udf_names.c:3:
In file included from C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\udf\udf.h:22:
In file included from C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\main\global.h:258:
In file included from C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\storage\var.h:10:
C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\10\Include\10.0.18362.0\shared\basetsd.h(322,12): warning: cast to 'void * __ptr32' from smaller integer type 'unsigned long' [-Wint-to-void-pointer-cast]
return((void * POINTER_32) (unsigned long) (ULONG_PTR) p);
^
In file included from udf_names.c:3:
C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\udf\udf.h(79,12): fatal error: 'ud_io1.h' file not found
# include "ud_io1.h"
^~~~~~~~~~
1 warning and 1 error generated.
scons: *** [udf_names.obj] Error 1
scons: building terminated because of errors.
(system "copy "C:\PROGRA~1\ANSYSI~1\v212\fluent"\fluent21.2.0\src\udf\sconstruct.udf "libudf\win64\2d_node\SConstruct" ")
1 archivo(s) copiado(s).
(system "copy "C:\PROGRA~1\ANSYSI~1\v212\fluent"\fluent21.2.0\src\udf\scons_default.bat "libudf\win64\2d_node\scons_test.bat" ")
1 archivo(s) copiado(s).
Creating user_nt.udf file for 2d_node ...
(system "copy "C:\PROGRA~1\ANSYSI~1\v212\fluent"\fluent21.2.0\src\udf\makefile_nt.udf "libudf\win64\2d_node\makefile" ")
1 archivo(s) copiado(s).
(chdir "libudf")(chdir "win64\2d_node")
D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_node>rem
D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_node>rem Copyright 1987-2021 ANSYS, Inc. All Rights Reserved.
D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_node>rem
"cl.exe" no se reconoce como un comando interno o externo,
programa o archivo por lotes ejecutable.
"clang-cl" no se reconoce como un comando interno o externo,
programa o archivo por lotes ejecutable.
scons: Reading SConscript files ...
scons: warning: No version of Visual Studio compiler found - C/C++ compilers most likely not set correctly
File "D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_node\SConstruct", line 8, in <module>
scons: warning: No version of Visual Studio compiler found - C/C++ compilers most likely not set correctly
File "D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_node\SConstruct", line 18, in <module>
Compiler used is "C:\PROGRA~1\ANSYSI~1\v212\fluent"\ntbin\clang\bin\clang-cl
Linker used is "C:\PROGRA~1\ANSYSI~1\v212\fluent"\ntbin\clang\bin\lld-link
scons: warning: No version of Visual Studio compiler found - C/C++ compilers most likely not set correctly
File "D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_node\SConstruct", line 148, in <module>
Copy("D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_node\resolve.exe", "C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\win64\resolve.exe")
c_sources ['UDFex1.C', 'udf_names.c']
c_sources_ []
scons: done reading SConscript files.
scons: Building targets ...
"C:\PROGRA~1\ANSYSI~1\v212\fluent"\ntbin\clang\bin\clang-cl /c /DUDF_EXPORTING /DUDF_NT /DWIN64 /EHa /wd4224 -Wno-return-type -Wno-implicit-function-declaration -Wno-comment -Wno-incompatible-library-redeclaration -Wno-reserved-user-defined-literal /clang:-std=c99 -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\win64\2d_node -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\main -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\addon-wrapper -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\io -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\species -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\pbns -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\numerics -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\sphysics -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\storage -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\mphase -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\bc -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\models -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\material -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\amg -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\util -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\mesh -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\udf -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\ht -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\dx -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\turbulence -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\acoustics -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\parallel -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\etc -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\ue -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\dpm -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\dbns -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\cortex\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\client\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\tgrid\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\PRIME\tgrid\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\multiport\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\multiport\mpi_wrapper\src -I C:\PROGRA~1\ANSYSI~1\v212\fluent\include -I "D:\Ingenieria Mecatronica\proyecto de grado (auxiliar de investigacion)\ejemplos\UDFexample\ejemplo1_files\dp0\FFF\Fluent\libudf\win64\2d_node" -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\MSVC\14.10.25017\include -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\x64\lib\clang\10.0.0\include -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\10\Include\10.0.18362.0\shared -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\10\Include\10.0.18362.0\ucrt -I C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\10\Include\10.0.18362.0\um udf_names.c
In file included from udf_names.c:3:
In file included from C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\udf\udf.h:22:
In file included from C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\main\global.h:258:
In file included from C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\storage\var.h:10:
C:\PROGRA~1\ANSYSI~1\v212\fluent\ntbin\clang\10\Include\10.0.18362.0\shared\basetsd.h(322,12): warning: cast to 'void * __ptr32' from smaller integer type 'unsigned long' [-Wint-to-void-pointer-cast]
return((void * POINTER_32) (unsigned long) (ULONG_PTR) p);
^
In file included from udf_names.c:3:
C:\PROGRA~1\ANSYSI~1\v212\fluent\fluent21.2.0\src\udf\udf.h(79,12): fatal error: 'ud_io1.h' file not found
# include "ud_io1.h"
^~~~~~~~~~
1 warning and 1 error generated.
scons: *** [udf_names.obj] Error 1
scons: building terminated because of errors.
Done.
AND the code tha I'm using
#include "udf.h"
static real velx=0.0;
DEFINE_CG_MOTION(box,dt,vel,omega,time,dtime)
{
NV_S(vel, =, 0.0);
NV_S(omega, =, 0.0);
velx= 0.05*sin(3.1415927 * time / 10.);
vel[0]=velx;
message("Time=%f, vel[0]=%f/n",time,vel[0]);
}
Relevant answer
error solved
Hi everyone, I solved the problem by reinstalling visual studio 2022, also the code had an inner error, lastly I followed this guide for solve other issues https://www.cfd-online.com/Wiki/Flue...with_Fluent_13 the new code /* Moving grid problem -CG movement of a box*/ #include "udf.h" static real velx = 0.0; DEFINE_CG_MOTION(box, dt, vel, omega, time, dtime) { NV_S(vel, =, 0.0); NV_S(omega, =, 0.0); velx = 0.05 * sin(3.1415927 * time / 10.); vel[1] = velx; Message("Time=%f, vel[1]=%f/n", time, vel[1]); }
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