aerosandbox.atmosphere
======================

.. py:module:: aerosandbox.atmosphere


Submodules
----------

.. toctree::
   :maxdepth: 1

   /autoapi/aerosandbox/atmosphere/_diff_atmo_functions/index
   /autoapi/aerosandbox/atmosphere/_isa_atmo_functions/index
   /autoapi/aerosandbox/atmosphere/atmosphere/index
   /autoapi/aerosandbox/atmosphere/thermodynamics/index


Classes
-------

.. autoapisummary::

   aerosandbox.atmosphere.Atmosphere


Package Contents
----------------

.. py:class:: Atmosphere(altitude = 0.0, method = 'differentiable', temperature_deviation = 0.0)

   Bases: :py:obj:`aerosandbox.common.AeroSandboxObject`


   All models here are smoothed fits to the 1976 COESA model;
   see AeroSandbox\studies\Atmosphere Fitting for details.



   .. py:attribute:: altitude
      :value: 0.0



   .. py:attribute:: method
      :value: 'differentiable'



   .. py:attribute:: temperature_deviation
      :value: 0.0



   .. py:attribute:: _valid_altitude_range
      :value: (0, 80000)



   .. py:method:: __repr__()


   .. py:method:: __getitem__(index)

      Indexes one item from each attribute of an Atmosphere instance.
      Returns a new Atmosphere instance.

      :param index: The index that is being called; e.g.,:
                    >>> first_atmosphere = atmosphere[0]

      Returns: A new Atmosphere instance, where each attribute is subscripted at the given value, if possible.




   .. py:method:: __len__()


   .. py:method:: __array__(dtype='O')

      Allows NumPy array creation without infinite recursion in __len__ and __getitem__.



   .. py:method:: pressure()

      Returns the pressure, in Pascals.



   .. py:method:: temperature()

      Returns the temperature, in Kelvin.



   .. py:method:: density()

      Returns the density, in kg/m^3.



   .. py:method:: density_altitude(method = 'approximate')

      Returns the density altitude, in meters.

      See https://en.wikipedia.org/wiki/Density_altitude



   .. py:method:: speed_of_sound()

      Returns the speed of sound, in m/s.



   .. py:method:: dynamic_viscosity()

      Returns the dynamic viscosity (mu), in kg/(m*s).

      Based on Sutherland's Law, citing `https://www.cfd-online.com/Wiki/Sutherland's_law`.

      According to Rathakrishnan, E. (2013). Theoretical aerodynamics. John Wiley & Sons.:
      This relationship is valid from 0.01 to 100 atm, and between 0 and 3000K.

      According to White, F. M., & Corfield, I. (2006). Viscous fluid flow (Vol. 3, pp. 433-434). New York: McGraw-Hill.:
      The error is no more than approximately 2% for air between 170K and 1900K.



   .. py:method:: kinematic_viscosity()

      Returns the kinematic viscosity (nu), in m^2/s.

      Definitional.



   .. py:method:: ratio_of_specific_heats()


   .. py:method:: mean_free_path()

      Returns the mean free path of an air molecule, in meters.

      To find the collision radius, assumes "a hard-sphere gas that has the same viscosity as the actual gas being considered".

      From Vincenti, W. G. and Kruger, C. H. (1965). Introduction to physical gas dynamics. Krieger Publishing Company. p. 414.




   .. py:method:: knudsen(length)

      Computes the Knudsen number for a given length.