radii = np.linspace(0.5, 1, 10)
thetas = np.linspace(0, 2 * np.pi, 20)
theta, r = np.meshgrid(thetas, radii)
dr = 1
dt = 1
f = plt.figure()
ax = f.add_subplot(111, polar=True)
How to make a quiver plot in polar coordinates