Cool Animations

animations and code

Hypersonic flow around a disk

One can reproduce this using the following code. The original Mathematica implementation has been described here.

import matplotlib.animation as animation
import matplotlib.pyplot as plt
import numpy as np
from matplotlib.patches import Circle

fig, ax = plt.subplots()
# change size of the figure
fig.set_size_inches(10, 10)


def update(t):

    ax.clear()
    disk = Circle((0, 0), radius=0.21, edgecolor="black", facecolor="blue")
    ax.add_patch(disk)

    # Time steps to add circles
    time_steps = np.arange(0, 100, 2)

    # All the physics is in this loop
    for step in time_steps:
        if t >= step:
            circle = Circle(
                (0.0151 * (step**2 - t**2), 0),
                radius=t - step,
                edgecolor="black",
                facecolor="none",
            )
            ax.add_patch(circle)

    ax.set_xlim(-30, 30)
    ax.set_ylim(-30, 30)
    # remove the axis
    ax.axis("off")


ani = animation.FuncAnimation(fig, update, frames=range(100), interval=5, blit=False)
# show the animation as a mp4 video
ani.save("hypersonic.mp4", writer="ffmpeg", fps=20)