I'm trying to pass the Interpreted UDF to Fluent 6.1. But the progrma generates the following messgae: line 1 parse error. Even when I'm trying to interpret HelloWorld UDF. Can anybody help me?

post your UDF !

I was trying to interpret the following example code (which is in documentation). Still no result...

#include "udf.h" /* must be at the beginning of every UDF you write */

DEFINE_PROFILE(inlet_x_velocity, thread, index) { real x[ND_ND]; /* this will hold the position vector */ real y; face_t f;

begin_f_loop(f, thread) /* loops over all faces in the thread passed

in the DEFINE macro argument */

{

F_CENTROID(x,f,thread);

y = x[1];

F_PROFILE(f, thread, index) = 20. - y*y/(.0745*.0745)*20.;

} end_f_loop(f, thread) }

For me it compiled and interpret well. Check your compiler.

Dear Arky

U check whether the udf file is in same folder as the case file u are running. What I have done is, first I've kept the same udf which u posted in my desktop and interpreted. It showed parse error.

Then I transferred to the case file folder and run the same udf. It interpreted well.

If u have still problems, write to me.

Regards Karthick

The UDF is in the folder that contains .cas and .dat files. I even tried to place the UDF source file, .cas and .dat files into ..\ntbin\ntx86, and still the same error. I suppose that something wrong with paths to some files, but I dont know exactly to which ones.

Dear Arky

Don't worry, it will not be a problem with ur udf. May be there may be a problem with ur path. I'll send u file helps to u set the path correctly to ur personal id.

Check it and then tell

Regards Karthick

Thanx a lot! i've installed MS VC and everything is working properly! Thanks again.

In windows you can fix the problem by simply launching fluent from the directory where your UDF and case files are, by typing fluent xxx (e.d 2dddp etc) on the dos prompt

[Shivani]

Hi
I am trying to studying the hydrodynamics and heat transfer in gas solid fluidised beds.
I am trying to use the modified drag law as a UDF.
************************************************** ***************
UDF for customizing the default Syamlal drag law in ANSYS FLUENT
************************************************** *****************/

#include "udf.h"
#define pi 4.*atan(1.)
#define diam2 3.e-4

DEFINE_EXCHANGE_PROPERTY(custom_drag,cell,mix_thre ad,s_col,f_col)
{
Thread *thread_g, *thread_s;
real x_vel_g, x_vel_s, y_vel_g, y_vel_s, abs_v, slip_x, slip_y,
rho_g, rho_s, mu_g, reyp, afac,
bfac, void_g, vfac, fdrgs, taup, k_g_s;

/* find the threads for the gas (primary) */
/* and solids (secondary phases) */

thread_g = THREAD_SUB_THREAD(mix_thread, s_col);/* gas phase */
thread_s = THREAD_SUB_THREAD(mix_thread, f_col);/* solid phase*/

/* find phase velocities and properties*/

x_vel_g = C_U(cell, thread_g);
y_vel_g = C_V(cell, thread_g);

x_vel_s = C_U(cell, thread_s);
y_vel_s = C_V(cell, thread_s);

slip_x = x_vel_g - x_vel_s;
slip_y = y_vel_g - y_vel_s;

rho_g = C_R(cell, thread_g);
rho_s = C_R(cell, thread_s);

mu_g = C_MU_L(cell, thread_g);

/*compute slip*/
abs_v = sqrt(slip_x*slip_x + slip_y*slip_y);

/*compute Reynold's number*/

reyp = rho_g*abs_v*diam2/mu_g;

/* compute particle relaxation time */

taup = rho_s*diam2*diam2/18./mu_g;

void_g = C_VOF(cell, thread_g);/* gas vol frac*/

/*compute drag and return drag coeff, k_g_s*/

afac = pow(void_g,4.14);

if(void_g<=0.85)
bfac = 0.8*pow(void_g, 1.28);
else
bfac = pow(void_g, 2.65);

vfac = 0.5*(afac-0.06*reyp+sqrt(0.0036*reyp*reyp+0.12*reyp*(2.*bfac-
afac)+afac*afac));
fdrgs = void_g*(pow((0.63*sqrt(reyp)/
vfac+4.8*sqrt(vfac)/vfac),2))/24.0;

k_g_s = (1.-void_g)*rho_s*fdrgs/taup;

return k_g_s;
}
This is the code I am using in the simulation.
Can someone help me in fixing this?



"C:/Users/s3798474/AppData/Local/Temp/UDF5.h.27452.0.c"
Error: C:/Users/s3798474/AppData/Local/Temp/UDF5.h.27452.0.c: line 1: parse error.

[AlexanderZ]

put

/*

on the first line

[Shivani]

Hi Alexandarz
Thanks.. It is working.

[aatifmoin]

Hii, i have the same error on Ansys 2023 R1. I've already installed MS VS 2019 on the pc but it neither compiles nor interprets.
Im trying to simulate a 2d water tank under an earthquake.

Just to try it out, this is the file im using for the compiler............
#include"udf.h"
DEFINE_ADJUST(ac,domain)
{
real gravity[3];
real time=0.0;
time=RP_Get_Real("flow-time");
gravity[0]=0.0;
gravity[1]=0.0;
gravity[2]=-9.81;
RP_Set_Real("gravity/x",gravity[0]);
RP_Set_Real("gravity/y",gravity[1]);
RP_Set_Real("gravity/z",gravity[2]);
}

[aatifmoin]

im also getting this error-
LINK : fatal error LNK1104: cannot open file 'kernel32.lib'

This is what i have installed from visual studio
https://drive.google.com/file/d/1j7K...usp=drive_link

Thanks in advance

[Shivani]

Hi
Can you try opening fluent using command line for visual studios.
I am posting link of you tube video for that
https://youtu.be/xt2hnE9_LdM?si=YzEDxttxUeEOPN4U

[aatifmoin]

Hii, thank you for the reply. I'm running Ansys 2023R1 this is older version that is shown here, the interface is quite different.

[aatifmoin]

I just made a .ttb file of the the expression i wanted to work with in Fluent, it was much easier.
Used this video for reference if anyone else needs help,
https://youtu.be/OiFSZgBOSGU?si=uQr8dBVrV11rm6Yz