Subsystem Atmosph

Atmosph computes some atmospheric properties, using the ICAO Standard Atmosphere model (see for instance ref.[1]). The block also computes the acceleration of gravity and the dynamic coefficient of viscosity. The block Atmosph is contained in the subsystem Airdata Group of the Beaver model. Other airdata (-related) variables are computed in the blocks Airdata1, Airdata2, and Airdata3, which also contained in the subsystem Airdata Group.

Inputvector: x

  x = [V alpha beta p q r psi theta phi xe ye H]'        (states)

 {V    : airspeed [m/s]                                         }
 {alpha: angle of attack [rad]                                  }
 {beta : sideslip angle [rad]                                   }
 {p    : roll rate [rad/s]                                      }
 {q    : pitch rate [rad/s]                                     }
 {r    : yaw rate [rad/s]                                       }
 {psi  : yaw angle [rad]                                        }
 {theta: pitch angle [rad]                                      }
 {phi  : roll angle [rad]                                       }
 {xe   : x-coordinate in Earth-fixed reference frame [m]        }
 {ye   : y-coordinate ''     ''          ''      ''  [m]        }
  H    : altitude above sea-level [m]

The variables which are not actually used by Atmosph have been displayed between curly braces.

Outputvector: yatm

  yatm = [rho ps T mu g]', (atmospheric properties)

  rho  : airdensity [kg/m^3]
  ps   : static pressure [N/m^2]
  T    : temperature [K]
  mu   : dynamic viscosity [kg/(m*s)]
  g    : acceleration of gravity [m/s^2]

References

  1. Ruijgrok, G.J.J. Elements of airplane performance. Delft University Press, Delft, The Netherlands, 1993.