[EminDikici]

Hello Everyone

I am a mechanical engineer and i need to complete my MSc homework about store seperation anaylsis in Ansys Fluent.

But i need to apply external force on missile but how can i do it i really dont know. I read some papes about it, they were writing UDF but i havent seen any examples in the internet.

Can you help me ?

[Chehade]

https://www.peopleperhour.com/freela...-body-6-664087

[Chehade]

Try this link maybe it can help.

[Zunair]

/************************************************** *****
SDOF property compiled UDF with external forces/moments
************************************************** *****/
#include "udf.h"
DEFINE_SDOF_PROPERTIES(delta_missile, prop, dt, time, dtime)
{
prop[SDOF_MASS] = 907.185;
prop[SDOF_IXX] = 27.116;
prop[SDOF_IYY] = 488.094;
prop[SDOF_IZZ] = 488.094;
/* add injector forces, moments */
{
register real dfront = fabs (DT_CG (dt)[2] -
(0.179832*DT_THETA (dt)[1]));
register real dback = fabs (DT_CG (dt)[2] +
(0.329184*DT_THETA (dt)[1]));
if (dfront <= 0.100584)
{
prop[SDOF_LOAD_F_Z] = 10676.0;
prop[SDOF_LOAD_M_Y] = -1920.0;
}
if (dback <= 0.100584)
{
prop[SDOF_LOAD_F_Z] += 42703.0;
prop[SDOF_LOAD_M_Y] += 14057.0;
}
}
printf ("\ndelta_missile: updated 6DOF properties")






Can any body help me out with these two statements of register real dfront and register rear dback....what is their purpose as the forces and moments are constant....(This is a code taken from ANSYS UDF manual).....any opinion about this is much appreciated