CAERO1

Bulk Data Entry Defines an aerodynamic macro element (panel) in terms of two leading edge locations and side chords. 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)
CAERO1 EID PID CP NSPAN NCHORD LSPAN LCHORD IGID
X1 Y1 Z1 X12 X4 Y4 Z4 X43

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
CAERO1 2000 2 3 2 1
1.0 0.0 0.0 3.0 0.1 0.0 0.9

Definitions

Field Contents SI Unit Example
EID Unique element identification number.

No default (Integer > 0)

 
PID Identification number of a PAERO1 property entry.
Integer
Specifies an identification number for this property.

No default (Integer > 0)

 
CP Coordinate system for locating points 1 and 4.

Default = 0 (Integer ≥ 0)

 
NSPAN Number of spanwise boxes.

If a positive value is specified, equal divisions are assumed.

If zero or blank, a list of division points is specified at the LSPAN field.

Default = blank (Integer ≥ 0)

 
NCHORD Number of chordwise boxes.

If a positive value is specified, equal divisions are assumed.

If zero or blank, a list of division points is specified at the LCHORD field.

Default = blank (Integer ≥ 0)

 
LSPAN ID of an AEFACT entry containing a list of division points for spanwise boxes. This is used only if the NSPAN field is zero or blank.

Default = blank (Integer > 0)

 
LCHORD ID of an AEFACT entry containing a list of division points for chordwise boxes. This is used only if the NCHORD field is zero or blank.

Default = blank (Integer > 0)

 
IGID Interference group identification. Aerodynamic elements with different IGIDs are uncoupled.

(Integer > 0)

 
X1, Y1, Z1 Location of point 1 in coordinate system CP.

(Real)

 
X4, Y4, Z4 Location of point 4 in coordinate system CP.

(Real)

 
X12, X43 Edge chord lengths in aerodynamic coordinate system.

(Real ≥ 0.0, but both fields should not be zero at the same time)

 

Comments

  1. The boxes and corner point nodes are numbered sequentially, beginning with EID. Be careful to ensure that all box and corner point node numbers are unique. There can be overlapping IDs between the structural and aerodynamic model, but result visualization will be affected. Similarly, non-unique corner IDs are allowed, but results cannot be visualized.
  2. The number of division points is one greater than the number of boxes. Therefore, if NSPAN = 3, the division points are 0.0, 0.333, 0.667, 1.000. If division points are specified, the first and last points do not need to be 0.0 and 1.0 (in which case, the corners of the panel would not be at the reference points).
  3. A triangular element is formed if X12 or X43 is set to 0.0.
  4. The element coordinate system is right-handed.
    Span direction is in Ye (1 to 4), and Chord direction is the Xe (from 1 to 2 or 4 to 3). First box ID of a panel is the same as the CAERO1 card ID. Then chordwise, the ID is incremented by one for subsequent boxes. After each chordwise strip, go back up to the next box along the span at the beginning of the panel and repeat the process.


    Figure 1. Element Coordinate System for Aerodynamic Panel
  5. The continuation line on the CAERO1 entry is mandatory.