AIM Inputs

The following list outlines the AVL inputs along with their default value available through the AIM interface.

• Mach = 0.0
  Mach number.
• Alpha = NULL
  Angle of attack [degree]. Either CL or Alpha must be defined but not both.
• Beta = 0.0
  Sideslip angle [degree].
• RollRate = 0.0
  Non-dimensional roll rate.
• PitchRate = 0.0
  Non-dimensional pitch rate.
• YawRate = 0.0
  Non-dimensional yaw rate.
• CDp = 0.0
  A fixed value of profile drag to be added to all simulations.
• CLAF = NULL (double)
  This scales the effective dcl/da of the section airfoil as follows:
  
  dcl/da = 2 pi ( 1 + CLaf t/c )
  
  where t/c is the airfoil's thickness/chord ratio. The intent is to better represent the lift characteristics of thick airfoils, which typically have greater dcl/da values than thin airfoils.
  
  A good 2D potential flow theory estimate for CLaf is 0.77.
  In practice, viscous effects will reduce the 0.77 factor to something less. Wind tunnel airfoil data or viscous airfoil calculations should be consulted before choosing a suitable CLaf value.
  
  This option is applied to all surface, and also be specified for individual surfaces using AVL_Surface Vortex Lattice Surface.
• AVL_Surface = NULL
  See Vortex Lattice Surface for additional details.
• AVL_Control = NULL
  See Vortex Lattice Control Surface for additional details.
• AVL_Operation = NULL
  See AVL Operation Constraints for additional details.
• CL = NULL
  Coefficient of Lift. AVL will solve for Angle of Attack. Either CL or Alpha must be defined but not both.
• AirfoilFiles = False
  If true, write airfoils to separate files. Otherwise airfoils are included in the .avl geometry file.
• Moment_Center = NULL, [0.0, 0.0, 0.0]
  Array values correspond to the Xref, Yref, and Zref variables. Alternatively, the geometry (body) attributes "capsReferenceX", "capsReferenceY", and "capsReferenceZ" may be used to specify the X-, Y-, and Z- reference centers, respectively (note: values set through the AIM input will supersede the attribution values).
• MassProp = NULL
  Mass properties used for eigen value analysis Structure for the mass property tuple = ("Name", "Value"). The "Name" of the mass component used for documenting the xxx.mass file.
  The Value is a JSON dictionary requires units, which depends whether unitSystem is specified (see AIM Units)
  If unitSystem is not specified:
  The value is a JSON dictionary with values with mass, CG, and moments of inertia information (e.g. "Value" = {"mass" : mass, "CG" : [x,y,z], "massInertia" : [Ixx, Iyy, Izz, Ixy, Ixz, Iyz]})
  and the values must be in units of kg, m, and kg*m^2
  The geometry must also be in units of m (without a capsLength attribute)
  If a unitSystem is specified:
  The value is a JSON dictionary with values with unit pairs for mass, CG, and moments of inertia information (e.g. "Value" = {"mass" : [mass,"kg"], "CG" : [[x,y,z],"m"], "massInertia" : [[Ixx, Iyy, Izz, Ixy, Ixz, Iyz], "kg*m2"]})
  The geometry must have a capsLength attribute, and the unitSystem must use units recognized by AVL.
  
  The components Ixy, Ixz, and Iyz are optional may be omitted.
• MassPropLink = NULL
  Mass properties linked from structural analysis for eigen value analysis Must be in units of kg, m, and kg*m^2 if unitSystem (see AIM Units) is not specified.
• Gravity = NULL
  Magnitude of the gravitational force used for Eigen value analysis. Must be in units of m/s^2 if unitSystem (see AIM Units) is not specified.
• Density = NULL
  Air density used for Eigen value analysis. Must be in units of kg/m^3 if unitSystem (see AIM Units) is not specified.
• Velocity = NULL
  Velocity used for Eigen value analysis. Must be in units of m/s if unitSystem (see AIM Units) is not specified.
• EigenValues = true
  If true, compute EigenValues when Gravity, Density, Velocity, and Mass properties are specified.