Aero input and outputs: Difference between revisions

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(Pasted info from old mailing-list)
 
(Added some info)
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'''Temp info from old mailing-list till get more info:'''
Properties aerodynamic functions in JSBSim can read and output.


There isn't much formal documentation at the moment that is available for
== Function inputs ==
the JSBSim properties. If you have some specific properties you'd like to
know about, post the queries here. For starters, here are the aerodynamic
properties (and definitions) of the Cessna 172:
 
  ********************
  ****** INPUTS ******
  ********************


Location of the aerodynamic reference point in the aircraft structural
Location of the aerodynamic reference point in the aircraft structural
Line 30: Line 23:
     /fdm/jsbsim/aero/ci2vel
     /fdm/jsbsim/aero/ci2vel


  *********************
== Function outputs ==
  ****** OUTPUTS ******
  *********************


Ground effect factors for lift and drag:
Ground effect factors for lift and drag:
Line 41: Line 32:
Runtime-created aerodynamic force and moment components from definitions in
Runtime-created aerodynamic force and moment components from definitions in
the <aerodynamics> section of the configuration file (varies per-aircraft):
the <aerodynamics> section of the configuration file (varies per-aircraft):
Lift coefficients:


     /fdm/jsbsim/aero/coefficient/CLwbh
     /fdm/jsbsim/aero/coefficient/CLwbh
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     /fdm/jsbsim/aero/coefficient/CLadot
     /fdm/jsbsim/aero/coefficient/CLadot
     /fdm/jsbsim/aero/coefficient/CLq
     /fdm/jsbsim/aero/coefficient/CLq
Drag coefficients:
     /fdm/jsbsim/aero/coefficient/CDo
     /fdm/jsbsim/aero/coefficient/CDo
     /fdm/jsbsim/aero/coefficient/CDDf
     /fdm/jsbsim/aero/coefficient/CDDf
Line 52: Line 48:
     /fdm/jsbsim/aero/coefficient/CDDe
     /fdm/jsbsim/aero/coefficient/CDDe
     /fdm/jsbsim/aero/coefficient/CDbeta
     /fdm/jsbsim/aero/coefficient/CDbeta
Side force coefficients:
     /fdm/jsbsim/aero/coefficient/CYb
     /fdm/jsbsim/aero/coefficient/CYb
     /fdm/jsbsim/aero/coefficient/CYda
     /fdm/jsbsim/aero/coefficient/CYda
Line 57: Line 56:
     /fdm/jsbsim/aero/coefficient/CYp
     /fdm/jsbsim/aero/coefficient/CYp
     /fdm/jsbsim/aero/coefficient/CYr
     /fdm/jsbsim/aero/coefficient/CYr
Roll moment coefficients:
     /fdm/jsbsim/aero/coefficient/Clb
     /fdm/jsbsim/aero/coefficient/Clb
     /fdm/jsbsim/aero/coefficient/Clp
     /fdm/jsbsim/aero/coefficient/Clp
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     /fdm/jsbsim/aero/coefficient/Clda
     /fdm/jsbsim/aero/coefficient/Clda
     /fdm/jsbsim/aero/coefficient/Cldr
     /fdm/jsbsim/aero/coefficient/Cldr
Pitch moment coefficients:
     /fdm/jsbsim/aero/coefficient/Cmalpha
     /fdm/jsbsim/aero/coefficient/Cmalpha
     /fdm/jsbsim/aero/coefficient/CmDf
     /fdm/jsbsim/aero/coefficient/CmDf
Line 68: Line 73:
     /fdm/jsbsim/aero/coefficient/Cmo
     /fdm/jsbsim/aero/coefficient/Cmo
     /fdm/jsbsim/aero/coefficient/Cmde
     /fdm/jsbsim/aero/coefficient/Cmde
Yaw moment coefficients:
     /fdm/jsbsim/aero/coefficient/Cnb
     /fdm/jsbsim/aero/coefficient/Cnb
     /fdm/jsbsim/aero/coefficient/Cnp
     /fdm/jsbsim/aero/coefficient/Cnp
Line 156: Line 164:


     /fdm/jsbsim/aero/qbar-area
     /fdm/jsbsim/aero/qbar-area
{{JSBSim}}

Revision as of 15:01, 6 March 2013

Properties aerodynamic functions in JSBSim can read and output.

Function inputs

Location of the aerodynamic reference point in the aircraft structural frame, measured in inches:

   /fdm/jsbsim/metrics/aero-rp-x-in
   /fdm/jsbsim/metrics/aero-rp-y-in
   /fdm/jsbsim/metrics/aero-rp-z-in

Maximum and minimum alpha (angle of attack) in degrees:

   /fdm/jsbsim/aero/alpha-max-deg
   /fdm/jsbsim/aero/alpha-min-deg

Wing span/(2*Velocity)

   /fdm/jsbsim/aero/bi2vel

Wing chord/(2*Velocity)

   /fdm/jsbsim/aero/ci2vel

Function outputs

Ground effect factors for lift and drag:

   /fdm/jsbsim/aero/function/ground-effect-factor-lift
   /fdm/jsbsim/aero/function/ground-effect-factor-drag

Runtime-created aerodynamic force and moment components from definitions in the <aerodynamics> section of the configuration file (varies per-aircraft):

Lift coefficients:

   /fdm/jsbsim/aero/coefficient/CLwbh
   /fdm/jsbsim/aero/coefficient/CLDf
   /fdm/jsbsim/aero/coefficient/CLDe
   /fdm/jsbsim/aero/coefficient/CLadot
   /fdm/jsbsim/aero/coefficient/CLq

Drag coefficients:

   /fdm/jsbsim/aero/coefficient/CDo
   /fdm/jsbsim/aero/coefficient/CDDf
   /fdm/jsbsim/aero/coefficient/CDwbh
   /fdm/jsbsim/aero/coefficient/CDDe
   /fdm/jsbsim/aero/coefficient/CDbeta

Side force coefficients:

   /fdm/jsbsim/aero/coefficient/CYb
   /fdm/jsbsim/aero/coefficient/CYda
   /fdm/jsbsim/aero/coefficient/CYdr
   /fdm/jsbsim/aero/coefficient/CYp
   /fdm/jsbsim/aero/coefficient/CYr

Roll moment coefficients:

   /fdm/jsbsim/aero/coefficient/Clb
   /fdm/jsbsim/aero/coefficient/Clp
   /fdm/jsbsim/aero/coefficient/Clr
   /fdm/jsbsim/aero/coefficient/Clda
   /fdm/jsbsim/aero/coefficient/Cldr

Pitch moment coefficients:

   /fdm/jsbsim/aero/coefficient/Cmalpha
   /fdm/jsbsim/aero/coefficient/CmDf
   /fdm/jsbsim/aero/coefficient/Cmq
   /fdm/jsbsim/aero/coefficient/Cmadot
   /fdm/jsbsim/aero/coefficient/Cmo
   /fdm/jsbsim/aero/coefficient/Cmde

Yaw moment coefficients:

   /fdm/jsbsim/aero/coefficient/Cnb
   /fdm/jsbsim/aero/coefficient/Cnp
   /fdm/jsbsim/aero/coefficient/Cnr
   /fdm/jsbsim/aero/coefficient/Cnda
   /fdm/jsbsim/aero/coefficient/Cndr

Alpha of the wing in radians (includes the angle of incidence of the wing, if input):

   /fdm/jsbsim/aero/alpha-wing-rad

Stall hysteresis, normalized:

   /fdm/jsbsim/aero/stall-hyst-norm

Angles of attack and sideslip in radians and degrees (and the magnitudes):

   /fdm/jsbsim/aero/alpha-rad
   /fdm/jsbsim/aero/beta-rad
   /fdm/jsbsim/aero/mag-beta-rad
   /fdm/jsbsim/aero/alpha-deg
   /fdm/jsbsim/aero/beta-deg
   /fdm/jsbsim/aero/mag-beta-deg

Dynamic pressure in psf:

   /fdm/jsbsim/aero/qbar-psf

Dynamic pressure in the body axis XZ plane:

   /fdm/jsbsim/aero/qbarUW-psf

Dynamic pressure in the body axis XY plane:

   /fdm/jsbsim/aero/qbarUV-psf

Time rate of change in alpha and sideslip in deg/sec and rad/sec:

   /fdm/jsbsim/aero/alphadot-rad_sec
   /fdm/jsbsim/aero/betadot-rad_sec
   /fdm/jsbsim/aero/alphadot-deg_sec
   /fdm/jsbsim/aero/betadot-deg_sec

Altitude of CG divided by wing span:

   /fdm/jsbsim/aero/h_b-cg-ft

Altitude of MAC divided by wing span:

   /fdm/jsbsim/aero/h_b-mac-ft

Aerodynamic rotational rates in rad/sec (includes wind effects, if any):

   /fdm/jsbsim/velocities/p-aero-rad_sec
   /fdm/jsbsim/velocities/q-aero-rad_sec
   /fdm/jsbsim/velocities/r-aero-rad_sec

Aerodynamic velocities in ft/sec (includes wind effects, if any):

   /fdm/jsbsim/velocities/u-aero-fps
   /fdm/jsbsim/velocities/v-aero-fps
   /fdm/jsbsim/velocities/w-aero-fps

The body axis aerodynamic force vector of the aircraft in lbs:

   /fdm/jsbsim/forces/fbx-aero-lbs
   /fdm/jsbsim/forces/fby-aero-lbs
   /fdm/jsbsim/forces/fbz-aero-lbs

The stability axis aerodynamic force vector of the aircraft in lbs:

   /fdm/jsbsim/forces/fwx-aero-lbs
   /fdm/jsbsim/forces/fwy-aero-lbs
   /fdm/jsbsim/forces/fwz-aero-lbs

The body axis aerodynamic moment vector of the aircraft in ft-lbs:

   /fdm/jsbsim/moments/l-aero-lbsft
   /fdm/jsbsim/moments/m-aero-lbsft
   /fdm/jsbsim/moments/n-aero-lbsft

The lift coefficient squared:

   /fdm/jsbsim/aero/cl-squared

Dynamic pressure times reference area:

   /fdm/jsbsim/aero/qbar-area