\chapter{برنامه نوشته شده برای نرم‌افزار فلوئنت}
\begin{latin}
\#include "udf.h"\\*
\\*
/*Constant Parameter Definition*/\\*
\#define J0 11.9281      \\*
\#define B0 1.0\\*
\#define a  0.01\\*
\#define Pi 3.14159\\*
\#define Th 0.12         \\*
\#define Ch 1.0          \\*
\#define D 5.0           \\*
\#define K 0.5           \\*
\#define ep 0.0000009 \\*
\\*
/*Define Source Term; X-Momentum Equation*/\\*
DEFINE\_SOURCE(xmom, c, t, dS, eqn)\\*
\{\\*
	real Z[ND\_ND];\\*
	real Airfoil\_Tet,Y\_Airfoil;  \\*
	real Xloc,Yloc,X,Y,R,Teta,Angle;     \\*   
    real Alpha,TIME,XDC,XC;                  \\*
    real source,Yprim,Eta;\\*
    FILE *fp2;\\*
   TIME=CURRENT\_TIME;\\*
    Alpha=0.1745329-D*0.01745329*sin(2.0*K*TIME);\\*
    C\_CENTROID(Z, c, t);\\*
	X=Z[0]; \\*
	Y=Z[1];\\*
	R=sqrt(pow(X,2)+pow(Y,2));\\*
    Teta=atan(Y/X);\\*
    if (X<=0.0)\\*
	\{\\*	
		Angle=fabs(Teta)-fabs(Alpha);\\
        Xloc=R*cos(Angle);\\*		
		Xloc=-Xloc;\\	*
	    Yloc=R*sin(Angle);\\*
	\}\\*
	if (X>0.0)\\*
	\{\\*
		if (Teta<(15.77777-Alpha))\\*
		\{\\*
          Angle=fabs(Teta)+fabs(Alpha);\\*
		  Xloc=R*cos(Angle);\\*
	      Yloc=R*sin(Angle);\\*
		\}\\*
		if (Teta==(15.77777-Alpha))\\
		\{\\*
	      Xloc=0.0;\\*
	      Yloc=R;\\*
		\}\\*
		if (Teta>(15.77777-Alpha))\\*
		\{\\*
           Angle=fabs(Teta)-fabs(Alpha);\\*
		   Xloc=R*cos(Angle);\\*
		   Xloc=-Xloc;\\*
	       Yloc=R*sin(Angle);\\*
		\}\\*
		\}\\*
	XDC=(Xloc+0.25)/Ch;\\*  
	XC=(Xloc+0.25)*Ch;  \\*
    Y\_Airfoil=(Th*Ch/0.2)*(0.2969*pow(XDC,0.5)-0.1260*XDC-0.3516*pow(XDC,2)\\*+0.2843*pow(XDC,3)-0.1015*pow(XDC,4));\\*
	Airfoil\_Tet=(Th*Ch/0.2)*(((0.2969/2.0)*sqrt(1.0/XC))-(0.1260/Ch)-(2.0*0.3516*XDC)\\*+(3.0*0.2843*pow(XDC,2))-(4.0*0.1015*pow(XDC,3)));\\*
	Yprim=Yloc-Y\_Airfoil;\\*
	Eta=(-Pi)/a;\\*
	source=J0*B0*exp(Eta*Yprim)*cos(fabs(Airfoil\_Tet-Alpha));\\*
	dS[eqn]=J0*B0*Eta*exp(Eta*Yprim)*cos(fabs(Airfoil\_Tet-Alpha));\\*
	return source;\\*
\}\\*
\\*
/*Define Source Term; Y-Momentum Equation*/\\*
DEFINE\_SOURCE(xmom, c, t, dS, eqn)\\*
\{\\*
	real Z[ND\_ND];\\*
	real Airfoil\_Tet,Y\_Airfoil;  \\*
	real Xloc,Yloc,X,Y,R,Teta,Angle;     \\   
    real Alpha,TIME,XDC,XC;                  \\*
    real source,Yprim,Eta;\\*
    FILE *fp2;\\*
   TIME=CURRENT\_TIME;\\*
    Alpha=0.1745329-D*0.01745329*sin(2.0*K*TIME);\\*
    C\_CENTROID(Z, c, t);\\*
	X=Z[0]; \\*
	Y=Z[1];\\*
	R=sqrt(pow(X,2)+pow(Y,2));\\*
    Teta=atan(Y/X);\\*
    if (X<=0.0)\\*
	\{\\*	
		Angle=fabs(Teta)-fabs(Alpha);\\*
        Xloc=R*cos(Angle);\\*		
		Xloc=-Xloc;\\*	    
	    Yloc=R*sin(Angle);\\*
	\}\\*
	if (X>0.0)\\*
	\{\\*
		if (Teta<(15.77777-Alpha))\\*
		\{\\*
          Angle=fabs(Teta)+fabs(Alpha);\\*
		  Xloc=R*cos(Angle);\\*
	      Yloc=R*sin(Angle);\\*
		\}\\*
		if (Teta==(15.77777-Alpha))\\*
		\{\\*
	      Xloc=0.0;\\*
	      Yloc=R;\\*
		\}\\*
		if (Teta>(15.77777-Alpha))\\*
		\{\\*
           Angle=fabs(Teta)-fabs(Alpha);\\*
		   Xloc=R*cos(Angle);\\*
		   Xloc=-Xloc;\\*
	       Yloc=R*sin(Angle);\\*
		\}\\*
		\}\\*
	XDC=(Xloc+0.25)/Ch;\\*  
	XC=(Xloc+0.25)*Ch;  \\*
    Y\_Airfoil=(Th*Ch/0.2)*(0.2969*pow(XDC,0.5)-0.1260*XDC-0.3516*pow(XDC,2)\\*+0.2843*pow(XDC,3)-0.1015*pow(XDC,4));\\*
	Airfoil\_Tet=(Th*Ch/0.2)*(((0.2969/2.0)*sqrt(1.0/XC))-(0.1260/Ch)-(2.0*0.3516*XDC)\\*+(3.0*0.2843*pow(XDC,2))-(4.0*0.1015*pow(XDC,3)));\\*
	Yprim=Yloc-Y\_Airfoil;\\
	Eta=(-Pi)/a;\\*
	source=J0*B0*exp(Eta*Yprim)*sin(fabs(Airfoil\_Tet-Alpha));\\*
	dS[eqn]=J0*B0*Eta*exp(Eta*Yprim)*sin(fabs(Airfoil\_Tet-Alpha));\\*
	return source;\\*
\}\\*
\\*
/*Motion of Oscillatory Airfoil*/\\*
DEFINE\_CG\_MOTION(airfoil, dt, vel, omega, time, dtime)\\*
\{\\
    Thread *t;\\*
	FILE *fp1;\\*
	int zone\_id;\\*
    real alpha;\\*
    t=DT\_THREAD(dt);\\*
    zone\_id=THREAD\_ID(t);\\*  
   omega[2]=0.0174532*D*2.0*K*cos(2.0*K*time);\\*
\}
\end{latin}