I want to know the meaning of the following expression.

1. real NV_VEC(psi), NV_VEC(A); 2. NV_D(psi, =, F_U(f,t), F_V(f,t), F_W(f,t)); 3. NV_S(psi, *=, F_R(f,t)) 4. NV_DS(psi_vec, =, F_U(f,t), F_V(f,t), F_W(f,t), *, dens);

VEC for vector, D for directions and S for scalar;

real NV_VEC(psi--- defines a vector psi[0]i+psi[1]j+psi[2]k

NV_D(psi,=,u,v,w)--- assigns values in 3directions to a vector

psi = ui+vj+wk

NV_S(psi,*=,R) => psi = psi * R (assigns/modifies magnitude)

NV_DS(psi_vec,=,u,v,w,*,dens) =>direction & scalar operations

psi_vec = (ui+vj+wk)*dens;

[vmtlv]

How about
real NV_VEC(A)
Mean of letter (A) in above code ?

[pitamber.methia]

NV_VV
NV_cross
NV_s
nv_v

pls can u elaborate the above commands

[zobekenobe]

A would be the Area vector

[S_Tanuj]

I want to shift the location of axis of rotation to some other point, then what changes needs to be made in UDF made for SHM???

[AlexanderZ]

Originally Posted by S_Tanuj

I want to shift the location of axis of rotation to some other point, then what changes needs to be made in UDF made for SHM???

which UDF do you use now?

[S_Tanuj]

For now, I am using below UDF:

#include "udf.h"
#define Freq 0.125
#define angular_freq 2.0*M_PI*Freq
#define tetmax 5.0*M_PI/180


DEFINE_ZONE_MOTION(TP8AMP05, omega, axis, origin, velocity, time, dtime)
{

N3V_D(velocity, = , 0.0, 0.0, 0.0);

*omega = tetmax*angular_freq*cos(angular_freq*time);

}


when I run the simulation using mesh motion, I can see the system moving, but rotation happens around Z-axis at (0,0,0) and it is ok because I did not give it the command to rotate about any other axis. I want the same, but I want the axis to be shifted below say at coordinate (0,0.5,0). Then what changes need to be made in UDF?

[Moulishwar]

Hi Tanuj,
You can specify the axis about which you wish to rotate the object under the Dynamic Mesh option in FLUENT.