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Dynamics  of Inviscid  Fluids                                                               79




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                             Figure  2.6.   The  pressure  distribution  around  the  airfoil






                                           y)
                                                           ;
                 (X,Y]=meshgrid(x, Z2=Z-zp1;
                                               ;Z=X+i*Y
                 PSI=U*imag(Z2+a~2./Z2+i*2*yp1*log(Z2/a))
                                                                                ;
                                                                           ;
                 c=contour(X,Y,PSI, [0  0])  ;axis(‘equal’)
                 z=c(1,:)+i*c(2,:);
                 for  j=i:length(c)  if  abs(z(j)-zpi)<a  z(j)=0;end;end;
                 f=z+b°2./z;
                 for  j=i:length(c)  if  abs(f£(j))>3  £(j)=0;end;end;
                 plot (f,/r.')  ;axis (‘equal’) ;hold  on;
                 c=contour(X,Y,PSI,  [-1:0.1:-0.1  0.1:0.1:1.5],’£");
                 axis (‘equal’)  ;

                 z=c(1,:)+i*c(2,:);
                 for  j=1:length(c)  if  abs(z(j)-zp1)<a  z(j)=0;end;end;
                 f=z+b°2./z;
                 for  j=1:length(c)  if  abs(f(j))>3  £(j)=0;end;end;
                                                       ;hold
                 plot  (f£,’k.’)  ;axis(‘equal’)
                                                               off;pause;
                 fi=linspace(0,2*pi,200);  z2=a*exp(i*fi)
                                                                              ;
                 zi=z2+zp1;  z=zit+b°2./z1;
                                                                       ./(1-(b./z1)
                                                                                          .72));
                 V=U*abs  ((1-(a./z2)  .~2+i*2*yp1./z2)
                                                                           ;
                 plot  (real (z)  ,1-(V/U)  .*2)  ;axis(‘equal’)
             5.5         An  Iterative  Method  for  Numerical
                         Generation  of  Conformal  Mapping

                 In  the  sequel,  we  will  present  a  method  for  the  approximate  construc-
             tion  of  conformal  mappings  for  arbitrary  shaped  obstacles  [87].
                 It  is  known  that  afunction  z  =  H(Z),  which  maps  conformally  the
             outside  of  a  profile  (c)  from  the  plane  (z)  onto  the  outside  of  a  disk  (C),

             of  radius  R,  from  the  plane  (Z),  can  be  represented  as  a  series
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