airdata3.hlp

MATLAB在飞行动力学和控制中应用的工具

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AIRDATA3 is a masked Simulink subsystem, used to compute the to-
tal temperature Tt and Reynolds numbers Re and Rc. Actually, the
Reynolds numbers are no 'airdata variables', but they are close-
ly related. Also, they are very important in aerospace engi-
neering, in particular for the evaluation of windtunnel experi-
ments. The block AIRDATA3 is contained in the subsystem 'Airdata
Group' of the system BEAVER.

Inputvectors: x, yatm, and yad1 (the inputvariables which are not
used by AIRDATA3 are displayed between accolades).
================================================================
  x    = [V alpha beta p q r psi theta phi xe ye H]'     (states)
  yatm = [rho ps T mu g]'   (atmospheric properties, computed in
                                               the block ATMOSPH)
  yad1 = [a M qdyn]'    (airdata variables, computed in AIRDATA1)

where:

  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]                           }

  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]                        }

 {a    : speed of sound [m/s]                                   }
  M    : Mach number [-]
 {qdyn : dynamic pressure [N/m^2]                               }

Outputvector: yad3.
===================
  yad3 = [Tt Re Rc]',

where:

  Tt   : total temperature [K]
  Re   : Reynolds number per m [1/m]
  Rc   : Reynolds number (using the mean aerodynamic chord as
         characteristic length) [-]

Parameters which must be set in the Matlab Workspace.
=====================================================
  GM1 = vector with some important geometrical properties of the
        'Beaver' aircraft, and the mass of the aircraft (which is
        assumed to be constant during the motions of interest).
        Here, the mean aerodynamic chord is needed, in order to
        find the Reynolds number Rc. GM1 can be loaded into the
        workspace from file if LOADER.M is called. Run MODBUILD.M
        first if the datafile does not yet exist. Type HELP
        LOADER or HELP MODBUILD for more details.

More info.
==========
See also ATMOSPH.HLP, AIRDATA1.HLP, AIRDATA2.HLP, and ADGRP.HLP
(ADGRP = 'Airdata Group').

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The FDC toolbox, Copyright Marc Rauw 1994-1998.