The equation for the streamlines for uniform flow over a cylinder is (x,y) = y y/x2

The equation for the streamlines for uniform flow over a cylinder is
ψ(x,y) = y – y/x2 + y2
where ψ is the stream function. For example, if ψ = 0, then y = 0. Since the equation is satisfied for all x, the x axis is the zero (ψ = 0) streamline. Observe that the collection of points where x2 + y2 = 1 is also a streamline. Thus, the stream function above is for a cylinder of radius 1. Make a 2-D contour plot of the streamlines around a cylinder with 1 in. radius. Set up the domain for x and y to range between -3 and 3. Use 100 for the number of contour levels. Add to the figure a plot of a circle with a radius of 1. MATLAB also plots streamlines inside the cylinder. This is a mathematical artifact.