Ambiance is a full implementation of the ICAO standard atmosphere 1993 written in Python.
- International Standard Atmosphere (Wikipedia)
- Manual Of The ICAO Standard Atmosphere - 3rd Edition 1993 (Doc 7488)
Usage
Atmospheric properties are computed from an "Atmosphere object" which takes the altitude (geometric height) as input. For instance, to simply retrieve sea level properties, you can write:
>>> from ambiance import Atmosphere
>>> sealevel = Atmosphere(0)
>>> sealevel.temperature
array([288.15])
>>> sealevel.pressure
array([101325.])
>>> sealevel.kinematic_viscosity
array([1.46071857e-05])List of available atmospheric properties
- Collision frequency (
collision_frequency) - Density (
density) - Dynamic viscosity (
dynamic_viscosity) - Gravitational acceleration (
grav_accel) - Kinematic viscosity (
kinematic_viscosity) - Layer names (
layer_name) [string array] - Mean free path (
mean_free_path) - Mean particle speed (
mean_particle_speed) - Number density (
number_density) - Pressure (
pressure) - Pressure scale height (
pressure_scale_height) - Specific weight (
specific_weight) - Speed of sound (
speed_of_sound) - Temperature (
temperature,temperature_in_celsius) - Thermal conductivity (
thermal_conductivity)
List-like input
Ambiance also handles list-like input (list, tuples, Numpy arrays). The following code demonstrates how to produce a temperature plot with Matplotlib. In the example, Numpy's linspace() function is used to produce an array with altitudes.
import numpy as np
import matplotlib.pyplot as plt
from ambiance import Atmosphere
# Make an atmosphere object
heights = np.linspace(-5e3, 80e3, num=1000)
atmosphere = Atmosphere(heights)
# Make plot
plt.plot(atmosphere.temperature_in_celsius, heights/1000)
plt.ylabel('Height [km]')
plt.xlabel('Temperature [°C]')
plt.grid()
plt.show()The output is
Matrix-like input
Similarly, you can also pass in entire matrices. Example:
>>> import numpy as np
>>> from ambiance import Atmosphere
>>> h = np.array([[0, 11, 12], [20, 21, 35], [0, 80, 50]])*1000
>>> h # Geometric heights in metres
array([[ 0, 11000, 12000],
[20000, 21000, 35000],
[ 0, 80000, 50000]])
>>> Atmosphere(h).temperature
array([[288.15 , 216.7735127 , 216.65 ],
[216.65 , 217.58085353, 236.51337209],
[288.15 , 198.63857625, 270.65 ]])
>>> Atmosphere(h).speed_of_sound
array([[340.29398803, 295.15359145, 295.06949351],
[295.06949351, 295.70270856, 308.29949587],
[340.29398803, 282.53793156, 329.798731 ]])
>>> Atmosphere([30000, 0]).layer_name
array(['stratosphere', 'troposphere'], dtype='<U42')For all functionality see the complete documentation.
Installation
Ambiance is available on PyPI and may simply be installed with
pip install ambiance
Requirements
Using Ambiance requires
- Python 3.6 or higher
- Numpy
For developers: Recommended packages may be installed with the requirements.txt.
pip install -r requirements.txt
License
License: Apache-2.0