[shivakumar]

Hi all,
I have been working on motion of fluid in side the aircraft drop tank. For my initial case fluid is moving to and fro. For this case I used the following code but is yeilding error. what is the problem? Any help would be greatly appreciated.

#include "udf.h"

DEFINE_ZONE_MOTION(fmotion, omega, axis, origin, velocity, time, dtime)
{
if(time<10)
{
omega = 10;
}
else
omega=0;

N3V_D(velocity,=,0.05*sin(omega*time), 0.0, 0.0);
}

Error reads

..\src\motion.c(14): warning: not enough actual motion parameters for macro 'NV_D'
..\src\motion.c(14): error C2109 subscripts requires pointer or error type
..\src\motion.c(14): error C2109 subscripts requires pointer or error type
..\src\motion.c(14): error C2109 subscripts requires pointer or error type

Thank you

[pakk]

In DEFINE_ZONE_MOTION, omega is a pointer. To assign a rotation, your code should be

*omega = 10;

Note the extra star.

I think this also causes your later problem: you try to take the sine of the pointer, where you should take the sine of the value.

N3V_D(velocity,=,0.05*sin(*omega*time), 0.0, 0.0);

Again, note the extra star.

[shivakumar]

Dear pakk,

Thank you for the reply. I just tried with the same code but this time no. of errors have been increased.

#include "udf.h"
DEFIINE_ZONE_MOTION(fmotion, omega, axis, origin, velocity, time, dtime)
{
	if(time<10)
	{
		*omega=10;
	}
	else
	{
		*omega=0;
	}
	
	N3V_D(velocity,=,0.05*sin(*omega*time), 0.0, 0.0);
}

Errors are

udf_names.c and user_nt.udf files in 3ddp_node are upto date.
(system "copy "C:\PROGRA~1\ANSYSI~2\v150\fluent"\fluent15.0.0\sr c\makefile_nt.udf "libudf\win64\3ddp_node\makefile" ")
1 file(s) copied.
(chdir "libudf")(chdir "win64\3ddp_node")# Generating ud_io1.h
zone_motion.c
..\..\src\zone_motion.c(7) : error C2100: illegal indirection
..\..\src\zone_motion.c(11) : error C2100: illegal indirection
..\..\src\zone_motion.c(14) : error C2109: subscript requires array or pointer type
..\..\src\zone_motion.c(14) : error C2100: illegal indirection
..\..\src\zone_motion.c(14) : error C2109: subscript requires array or pointer type
..\..\src\zone_motion.c(14) : error C2109: subscript requires array or pointer type

Done.


Also i tried it in another way, For Example

Int x;
int *omega;
omega=&x;

and this too didnt work.


Thank you

[shivakumar]

I solved this problem with DEFINE_SOURCE. I'm moving to the next case i.e, accelerating the Drop tank using the same macro.