how to change flow visualization to not intercept the airfoil

how do i change the flow to not intercept the airfoil even when i change the shape of airfoil flow,Here is my code.

U = 4;
alpha = 20;                % angle of attack, deg
alpha = alpha*pi/180;       % angle of attack in radians
beta = (alpha);
Ek = 0.3;                 % displacement of circle center in  real axis. // velocity potential
Em = 0.1   ;                 % displacement of circle center in  imaginary axis.  // stream function
Z0 = -Ek/4 + 1i*(Em/4);              % resultant displacement in the z plane 
r = 0.45;  
k = 2*r*U*sin(beta+alpha);
a = r-Z0;
tol = +5e-20;
[x y]= meshgrid(-5:.01:5);
z = x + 1i*y;
w = U * exp(-1i*alpha);
% grid tolerance check for flow visualization 
for p = 1:length(x)
    for q = 1:length(y)
        if abs(z(p,q)-(Z0)) <=  r - tol
            z(p,q) = NaN;
        end
    end
end

for p = 1:length(x)
    for q = 1:length(y)
        f(p,q) = w*(z(p,q)-Z0) + (U*exp(1i*alpha)*r^2)./(z(p,q)-Z0) + 1i*k*log(z(p,q)-Z0); 
        J(p,q) = z(p,q)+a^2./z(p,q);  % grid in the airfoil plane
    end 
end 
phi = 0:.05:2*pi;   
for p = 1:length(phi)
    
    zcylin(p) = r*(exp(1i*phi(p))) + Z0;
    zair(p) = zcylin(p)+(a^2./(zcylin(p)));
end 
figure(2)
hold on
v2 = -100:1:100;
contourf(real(J),imag(J),imag(f),v2);
fill(-real(zair),imag(zair),'k')
axis equal
axis(2*[-1 1 -1 1])
title('Streamline around airfoil. ');

[Karan Singh]

Hey Matthew, to address your question about changing the flow to not intercept the airfoil even when you change the shape of the airfoil, I would need a deeper understanding of the specific problem you are trying to solve and the context of the code you provided. Could you please provide more details about the issue you are facing or any specific requirements you have for the flow behavior around the airfoil?

[Matthew]

Hey Karan, My problem is when i change number of Ek and Em the shape of airfoil is change too .but some of the streamline that stay around the airfoil is intercept airfoil and flow seem not smooth so i wonder what code do i need to change or adapt.

[Matthew]

for example when i change value of both Ek,Em to 0.1 and change the alpha to 50 deg ,the figure will show that airfoil is intercept with streamline