Path: ACPro/ACProAerodynamics

   Computes lift and drag coefficients for a vehicle using simple formulas. 
   You will have to call this routine for the wing, fuselage and tail
   separately using different characteristic lengths. The wing and tail use
   the mean chord and the fuselage uses the length. 
   Altitude and velocity must be the same length.

   zetaTrans is a "fudge" factor to prevent the form drag from becoming
   infinite at M = 1. m0 is another "fudge" factor that prevents the 
   skin friction from going to infinity at Mach = 0. It fits a linear
   function to the skin friction curve whose value and slope match the
   curve at that Mach number.

   If wing area is not entered it computes lift and drag per unit area.

   Type LiftAndDrag for a demo.
   Since version 3 (ACT).
   y = LiftAndDrag( d, altitude, velocity, cP, alpha )

   d              (1,1)  Aircraft parameters
                         .length      (1,1) Representative length (e.g. mean chord) (m)
                         .oswaldEff   (1,1) Oswald efficiency factor (0.9 to 1.0)
                         .aspectRatio (1,1) Aspect ratio for wing (length/mean chord)
                         .thickness   (1,1) Ratio of length to thickness
                         .s           (1,1) Area (m^2) optional
                         .zetaTrans   (1,1) Damping for transonic
                         .sweep       (1,1) Sweep angle
                         .a0          (1,1) Lift curve slope
                         .alpha0      (1,1) Zero lift angle of attack
                         .m0          (1,1) Mach number for linear skin
                                            friction coefficient
   altitude       (1,n)  Altitude (m)
   velocity       (1,n)  Velocity at altitude (m/sec)
   cP             (1,1)  Parasitic drag coefficient
   alpha          (1,n:) Angle of attack (rad)

   y              (1,1)  Output data structure
                         .reynoldsNumber (1,n) Reynold's number
                         .skinFriction   (1,n) Skin friction
                         .formDrag       (1,n) Form drag
                         .kInduced       (1,n) Drag induced due to lift
                         .parasiticDrag  (1,n) Parasitic drag
                         .cD0            (1,n) Zero lift drag coefficient
                         .cD             (1,n) Drag coefficient
                         .cLOpt          (1,n) Optimal lift coefficient.
                         .cL             (1,n) Lift coefficient.
                         .lift           (1,n) Lift
                         .drag           (1,n) Drag
                         .loading        (1,n) Wing loading

   See also InducedDragCoeff, SkinFrictionCoeff and FormDragCoeff, 
   LiftCoeff, DragCoeff, AircraftDragDataStructures.
   Reference: Miller, R. "16.751 Class Notes," MIT, 1977.


ACPro: ACProAerodynamics/DragCoeff
ACPro: ACProAerodynamics/LiftCoeff
Common: Atmosphere/StdAtm
Common: Graphics/Plot2D
Math: Trigonometry/CosD

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