Matlab code for a uniform flow flowing in X-direction having equipotential lines and streamlines is

U = 1; % Uniform stream

% GRID:

x = -4:.04:4;

y = -4:.04:4;

for m = 1:length(x)

for n = 1:length(y)

xx(m,n) = x(m); yy(m,n) = y(n);

% Velocity potential function:

phi_UniFlow(m,n) = U * x(m);

% Stream function:

psi_UniFlow(m,n) = U * y(n);

end

end

% Plots

% Uniform stream in x direction:

contour(xx,yy,psi_UniFlow,[-3:0.5:3],'k'),hold on

contour(xx,yy,phi_UniFlow,[-3:1:3],'r')

axis image,hold off

title('Uniform stream flow in x direction')

xlabel('x'),ylabel('y')

Equipotential lines and streamlines