[el123]

I am trying to write a UDF to make 4 aerofoils pitch about their quarter-chord point in a sinusoidal fashion as they rotate about a common point (think cross flow fan with variable pitch).
I am a bit confused on what macros to use as I don't want a dynamic mesh and am using a sliding mesh with transient profile macro currently.
See below for what I have so far (and picture for my set-up). Depending on what axis of rotation I put in the boundary conditions in fluent I can only get them to either rotate about the common point (0,0) or pitch about their quarter chord points, not both?

I know my question is a bit vague but if anyone could help me with how I should go about them rotating AND pitching that would be amazing!

UDF:

#include "udf.h"
#define PI 3.141592654
real theta_max = 35 * (PI/180);
real omega = 420 * (2 * PI/60);

DEFINE_TRANSIENT_PROFILE(ypos, time)
{
real phi_start = 90 * (PI/180);
real theta_dot = theta_max * omega * cos((omega * time) + phi_start);
return theta_dot;
}

DEFINE_TRANSIENT_PROFILE(yneg, time)
{
real phi_start = 270 * (PI/180);
real theta_dot = theta_max * omega * cos((omega * time) + phi_start);
return theta_dot;
}

DEFINE_TRANSIENT_PROFILE(xpos, time)
{
real phi_start = 0 * (PI/180);
real theta_dot = theta_max * omega * cos((omega * time) + phi_start);
return theta_dot;
}

DEFINE_TRANSIENT_PROFILE(xneg, time)
{
real phi_start = 180 * (PI/180);
real theta_dot = theta_max * omega * cos((omega * time) + phi_start);
return theta_dot;
}