[minhaj_iut]

Dear All,

I am trying to track the weld surface deformation with the help of VOF model. I am considering a 3D transient model where laser beam is striking on the metal surface as heat source. I have written a UDF for this heat source. It works well. For melting the surface, solidification/melting model has been incorporated. Now I would like to track the VOF model. But I am confused how the computational domain should look like for VOF model? For tracking surface deformation, do I need to write any udf for surface tension/forces? In my model, I am not considering key hole. Any advice will be highly appreciated.

Regards
Minhaj

[Lokesh_Reddy]

HI
I'm simulating the laser weld to study weld pool behavior like marangoni effects and temperature gradients from weld region to the cooler region . Can anybody with prior experience have written any UDF for moving Heat source and for the simulation for the marangoni effect in the weld pool.

[Lokesh_Reddy]

Hi der, could share your udf so that I can get an idea how to start writting for my simulation purpose

[piyupant]

Originally Posted by Lokesh_Reddy

Hi der, could share your udf so that I can get an idea how to start writting for my simulation purpose

Friend, if you are looking for DEFINE_SOURCE, here is the UDF for moving gaussian profile laser.

#include "udf.h"
#include "unsteady.h"
#define ETA 0.25
#define POWER 1000.0
#define PI 3.14156
#define RQ 0.0005 /* radius of laser beam */

DEFINE_SOURCE(energy_source, c, t, dS, eqn)

/*This checks whether the cell is within laser beam span- if inside put intensity else zero intensity */
{
real source;
real x[ND_ND];
real rmag,rmag1;

C_CENTROID(x,c,t);

x[0]=x[0]+0.015*CURRENT_TIME;
rmag=(x[0])*(x[0])+(x[2])*(x[2]);
rmag1=sqrt(rmag);

if( x[1]<0.0 && x[1]>0-0.001)
{
if( rmag< RQ )
source = (ETA*POWER)/(PI*RQ*RQ)*exp(-2*rmag1*rmag1/(RQ*RQ));
else
source = dS[eqn]= 0.0;
}
else
source =0.0;
return source;
}

[ARJUN A ASOK]

when i run this code it is shown " recieved a fatal signal (segmentation fault) " .
Is there any way out

[Aaronaiy]

Originally Posted by piyupant

Friend, if you are looking for DEFINE_SOURCE, here is the UDF for moving gaussian profile laser.

#include "udf.h"
#include "unsteady.h"
#define ETA 0.25
#define POWER 1000.0
#define PI 3.14156
#define RQ 0.0005 /* radius of laser beam */

DEFINE_SOURCE(energy_source, c, t, dS, eqn)

/*This checks whether the cell is within laser beam span- if inside put intensity else zero intensity */
{
real source;
real x[ND_ND];
real rmag,rmag1;

C_CENTROID(x,c,t);

x[0]=x[0]+0.015*CURRENT_TIME;
rmag=(x[0])*(x[0])+(x[2])*(x[2]);
rmag1=sqrt(rmag);

if( x[1]<0.0 && x[1]>0-0.001)
{
if( rmag< RQ )
source = (ETA*POWER)/(PI*RQ*RQ)*exp(-2*rmag1*rmag1/(RQ*RQ));
else
source = dS[eqn]= 0.0;
}
else
source =0.0;
return source;
}

Hello, did you do some simulation about the evaporation involved in the welding?