gistfile1.txt

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Sat Nov 26 12:42:00 2022

@author: tommasoprocida
"""


import math
import numpy as np
import matplotlib.pyplot as plt

Cd = 1
p = 1.2
A = 0.8
k = (Cd * p * A)/2
m = 100
g =  9.81

NumPoints = 2000
tmin = 0.0
yvals = np.zeros(NumPoints)
vyvals = np.zeros(NumPoints)


print("This section will explore Baumgartner's approach of the sound barrier.")
print()
gamma = 1.4
R = 8.3145
M = 0.0289645


dt = 0.1
tvals = np.arange(0, 1000, dt)
yvals = np.zeros(len(tvals))
vyvals = np.zeros(len(tvals))
p0 = 1.2
h = 7640
yvals[0] = 39045
v0 = 0
Vs = np.zeros(len(tvals))

for n in range(len(tvals)):
    py = p0 * math.exp(-yvals[n]/h)
    ky = (Cd * py * A)/2


    vyvals[n+1] = vyvals[n] - (dt * (g + ((ky/m) * abs(vyvals[n]) * vyvals[n])))
    yvals[n+1] = yvals[n] + (dt * vyvals[n])
    tvals[n+1] = tvals[n] + dt

    if yvals[n] > 25100:
        T = 141.3 + (0.0030 * yvals[n])
        Vs[n] = math.sqrt((gamma * R * T)/M)

    elif yvals[n] < 11000:
        T = 288 - (0.0065 * yvals[n])
        Vs[n] = math.sqrt((gamma * R * T)/M)

    else:
        T = 216.5
        Vs[n] = math.sqrt((gamma * R * T)/M)


    if yvals[n+1] <= 0:
        break

tvals = tvals[:n+1]
yvals = yvals[:n+1]
vyvals = vyvals[:n+1]
Vs = Vs[:n+1]


fig ,(ax1) = plt.subplots(1, figsize = (12,4))
fig . suptitle('Velocity data for Newtonian freefall with varying drag')
ax1.set(xlabel='Time (s)', ylabel='Speed (m/s))', title='Altitude')
ax1.plot(tvals, Vs, 'tab:red', label="Speed of Sound")
ax1.plot(tvals, -vyvals, 'tab:green', label="Speed of Baumgartner")
plt.legend(loc="center right")
plt.show()

maxspeed = -(min(vyvals))

print()
supersonic = []

# list.append() appends the entire argument as a single list item
supersonic.append(np.where(abs(vyvals) >= Vs))
# so now your list contains just one item

# but now you redefine supersonic anyway:
supersonic = np.array(supersonic, dtype=int)*dt


print("The times Baumgartner is travelling at supersonic speeds are:",supersonic, "seconds")
print("A total of 18 seconds")
print("The maximum speed reached by Baumgartner on his descent was", maxspeed, "m/s")