PAERO2

Bulk Data Entry Defines the cross-sectional properties of slender bodies. This is used for Vortex Lattice Method (VLM) and Doublet Lattice Method (DLM) in subsonic aeroelastic analysis.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
PAERO2 PID ORIENT WIDTH AR LRSB LRIB LTH1 LTH2
THI1 THN1 THI2 THN2 THI3 THN3

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
PAERO2 3 ZY 2.5 1.0 300 200
1 10

Definitions

Field Contents SI Unit Example
PID Property identification number. This is to be referenced by a CAERO2 Bulk Data Entry.

No default (Integer > 0)

ORIENT Orientation flag. Type of motion allowed for bodies defined in the aerodynamic coordinate system of ACSID. See AERO Bulk Data Entry.

No default (Character = “Z”, “Y”, or “ZY”)

WIDTH Reference the half-width of body and the half-width of the constant width interference tube.

No default (Real > 0.0)

AR Aspect ratio of the interference tube which is calculated as the height of the tube divided by the width.

No default (Real > 0.0)

LRSB Identification number of an AEFACT entry containing a list of slender body half-widths at the end points of the slender body elements.
Integer ≥ 0
0 or blank
Value of WIDTH is used.
LRIB Identification number of an AEFACT entry containing a list of interference body half-widths at the end points of the interference elements.
Integer ≥ 0
0 or blank
Value of WIDTH is used.
LTH1 Identification number of AEFACT entries for defining θ1 arrays for interference calculations.

Default = blank (Integer ≥ 0)

LTH2 Identification number of AEFACT entries for defining θ2 arrays for interference calculations.

Default = blank (Integer ≥ 0)

THIi, THNi The first and last interference element of a body to use the θ1 array; the others use the θ2 array.

No default for THI1 and THN1 (Integer > 0)

Default = blank for THI2/3 and THN2/3 (Integer ≥ 0)

Comments

  1. The half-widths (given on AEFACT entries referenced in fields 6 and 7) are specified at division points. The number of entries on an AEFACT entry used to specify half-widths must be one greater than the number of elements.
  2. THIi and THNi are interference element numbers on a body. The first element is one for each body. If THI1~3 and THN1~3 are all defined, the union of [THI1, THN1], [THI2, THN2] and [THI3, THN3] defines the complete set of interference elements using the θ1 array.
  3. A body is represented by a slender body surrounded by an interference tube. The slender body creates the downwash due to the motion of the body, while the interference tube represents the effects upon panels and other bodies.
    Figure 1. Idealization of Aerodynamic Body


  4. The angles θ1 and θ2 are input in degrees using the aerodynamic element coordinate system as the reference coordinate system for defining the theta points.
  5. Distribution of the theta points does not need to be uniform. A theta point must be placed a finite distance (instead of zero distance) from any aerodynamic box edge; preferably the box edge is equidistant from any two theta points located on the two sides of that box.
  6. For half models, the theta arrays LTH1 and LTH2 should encompass a full 360-degree range.