Wing definition

@WING_DEFINITION {
@WING_NAME {WingName} {
@WING_VELOCITY {Vw}
@WING_LENGTH {Lw}
@WING_FRAME_NAME {wingFrameName}
@LIFTING_LINE_LIST {LfnName1, LfnName2,... LfnNameN}
@INFLOW_NAME {InflowName}
@SENSOR_NAME {sensorName}
@COMMENTS {CommentText}
}
}

NOTES

  1. A wing is a component of an aerodynamic model and is defined as a collection of lifting lines.
  2. The wing is characterized by a velocity, Vw, typically the far field flow velocity, and the wing length, Lw.
  3. The definition of the axis systems associated with the wing relies on the definition of the wing frame wingFrameName.
  4. The wing is associated with a collection of lifting lines. The list of lifting lines, LfnName1, LfnName2, ..., LfnNameN, specifies all the lifting lines associated with this wing.
  5. The induced flow generated by the unsteady circulation associated with the lifting lines of this wing can be evaluated using an inflow model, InflowName.
  6. It is possible to attach comments to the definition of the object; these comments have no effect on its definition.

Sensors

Sensors can be defined to extract information about wings. The following SensorType and associated FrameName specifications are allowed for wings: TOTAL_AIRLOADS. (Default value: TOTAL_AIRLOADS).

No u value or v value are accepted for wings.

Axis systems

Figure 1 shows the axis systems used to represent typical problems. Although the conventions might be slightly different from one code to the other, the following axis systems are typically present.

  1. The Inertial frame is defined as FI = [O, I = (i1, i2, i3)], where point O is an inertial point and B a fixed orthonormal basis. This is the fundamental inertial frame used in the dynamic analysis.
  2. The Fuselage frame is defined as FF = [C, BF = (f1, f2, f3)], where point C is center of mass of the aircraft and BF a body attached orthonormal basis. f1 is pointing to the front of the aircraft, f2 is pointing to the right of the aircraft, and f3 is pointing down. This system defines the directions forwards (or backwards), right (or left), and downwards (or upwards), on the aircraft, even in the case of a maneuver involving large angle rotations for the aircraft.
  3. The Wing root frame is defined as FR = [R, BR = (r1, r2, r3)], where point R is at the root of the wing and BR an orthonormal basis. r1 is pointing right, r2 back, and r3 down the aircraft.
  4. The Wing frame is defined as FW = [W, BW = (w1, w2, w3)], where point W is the hub point and BW a body attached orthonormal basis. w1 is pointing along the wing in its reference, un-deformed configuration, w2 towards the leading edge and w3 is pointing upwards.
  5. The Airstation frame is defined as FA =[A, BA = (a1, a2, a3)]), where point A is at the airstation location on the wing and BA a wing attached orthonormal basis. This system is moving with the wing. a1 is pointing towards the wing tip, a2 towards the leading edge and a3 is pointing upwards. One airstation frame is defined for each airstation. These frames are indirectly defined together with the lifting line: the frame has its origin at the location of the airstation. The orientation of the frame is determined by the triad defined at the airstation. Finally, the motion of the airstation is dictated by that of the associated beams, see section airstation motion.
Figure 1. Axis systems for a wing.

These frames are defined in the following manner.

  1. The fuselage frame, FF. This frame is a fixed frame if the aircraft fuselage center of mass is an inertial point, or a moving frame if the fuselage center of mass is moving, as would be the case for maneuvering flight. The fuselage frame is defined with the aerodynamic interface.
  2. The wing root frame, FR. This frame is a fixed frame if the root of the wing is an inertial point, or a moving frame if the wing is moving. The wing root frame, wingFrameName, is defined in present section.
  3. One wing frame, FW, per wing. These are moving frames moving with the wings. A wing frame must be defined for each wing and is attached at the root of the wing. The wing frames are defined together with the lifting line associated with the wing.
  4. One airstation frame, FA, per airstation. These frames are indirectly defined together with the lifting line: the frame has its origin at the location of the airstation. The orientation of the frame is determined by the triad defined at the airstation. Finally, the motion of the airstation is dictated by that of the associated beams, see section airstation motion.