44 lines
993 B
Python
44 lines
993 B
Python
import numpy as np
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import matplotlib.pyplot as plt
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def temperature(altitude):
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if altitude > 25000:
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return -131.21 + 0.00299*altitude
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elif altitude > 11000:
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return -56.46
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else:
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return 15.04 - 0.00649*altitude
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def pressure(altitude):
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T = temperature(altitude)
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if altitude > 25000:
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kpa = 2.488 * ((T+273.1)/216.6)**(-11.388)
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elif altitude > 11000:
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kpa = 22.65 * np.exp(1.73 - 0.000157*alititude)
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else:
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kpa = 101.29 * ((T+273.1)/288.08)**5.256
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return 1000*kpa
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def atmospheric_density(altitude):
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p = pressure(altitude)
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T = temperature(altitude)
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return p / (286.9*(T+273.1))
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def Mach(altitude, speed):
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return speed/speed_of_sound(altitude)
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def speed_of_sound(altitude):
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gamma = 1.4
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p = pressure(altitude)
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rho = atmospheric_density(altitude)
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return (gamma*p/rho)**0.5
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def dynamic_pressure(altitude, speed):
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rho = atmospheric_density(altitude)
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return rho * speed**2 / 2
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