PANELG

Bulk Data Entry Defines a set of grid points and/or elements as a generic panel.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
PANELG ID NAME TYPE ESID GSID SURF ERPRLF    

Definitions

Field Contents SI Unit Example
ID Unique panel identification number.

No default (Integer > 0)

 
NAME Panel label.

No default (Character string)

 
TYPE Panel types:
PFP
Indicates that the panel should be considered for panel participation output (similar to PANEL). PFP panels can be specified as a set of grid points or as a set of elements.
ERP
Indicates that the panel should be considered for equivalent radiated power output (similar to ERPPNL).
SOUND
Indicates that the panel should be considered for radiated sound output.
ACPOWER
Indicates that the acoustic power is output for panels defined by the PANELG entry.
Blank (Default) 1 2 3
Indicates that the panel should be considered in any context involving panels. This is not applicable to ACPOWER.
 
ESID Set identification number for a set of elements.

No default (Integer > 0 or blank)

 
GSID Set identification number for a set of grids.

No default (Integer > 0 or blank)

 
SURF Surface identification number for the panel where acoustic power is desired. 4

No default (Integer > 0 or blank)

 
ERPRLF Radiation Loss Factor used in the Equivalent Radiated Power (ERP) calculation. A real value can be specified to directly define the Loss Factor for all frequencies. An Integer value can be specified to reference a TABLEDi entry that defines the Loss Factor versus Frequency table.

For this particular panel, the Loss Factor value specified in this field overrides the loss factor specified via PARAM, ERPRLF.

If this field is blank, the Loss Factor value specified via PARAM, ERPRLF will be used.

No default (Real > 0.0 or Integer > 0 or blank)

 

Comments

  1. Panels of type ERP/SOUND may be defined as a set of elements, a set of grid points, or both. If a set of elements is defined, the panel will consist of all grid points connected to these elements. If both sets are defined, the panel will consist of the intersection of those sets. Panels of type PFP must be defined as a set of grid points or a set of elements.
  2. It is always recommended to explicitly define the panel type (TYPE field). However, if the TYPE field is blank, and the panel is used for panel participation output (PFP), the panel should always be defined as a set of grid points. Alternatively, if the TYPE field is blank, and the panel is used for ERP/SOUND output, then it may be defined either as a set of grid points or a set of elements.
  3. The element set can also consist of solid elements. In such cases, grids on the wetted surface are automatically detected to define the panel.
  4. SURF entry is valid only when ACPOWER output is desired (TYPE = ACPOWER). In this case, only surfaces of type ELFACE are considered.
  5. When TYPE = ACPOWER:
    • The following elements are considered for the element set (corresponding to ESID):
      2D
      Fluid PLOTEL with 3 or 4 nodes, CAABSF with 3 or 4 nodes, CACINF3 or CACINF4
      3D
      Cavity fluid elements, only for the skin interfacing with structure and the skin that is acoustically rigid
    • All the elements connected to the grids in the grid set (corresponding to GSID) will be considered.
    • The following elements are considered for the surface definition (corresponding to SURF).
      2D
      CAABSF with 3 or 4 nodes, CACINF3 or CACINF4
      3
      Cavity fluid elements
    • The direction of the surface normal used for calculation of acoustic power is defined as:
      • In the case of element (ESID) and grid (GSID) sets for 2D definitions, the direction of the normal is based the order of the nodal numbering i.e. an anticlockwise nodal numbering leads to an outward surface normal and vice-versa.
      • In the case of element (ESID) and grid (GSID) sets for 3D definitions, the direction of the normal is into the element.
      • In the case of surfaces (SURF) for 2D definitions, the direction of the normal is based on the order of the nodal numbering i.e. an countter-clockwise nodal numbering leads to an outward normal and vice-versa.
      • In the case of surfaces (SURF) for 3D definitions, the direction of the surface normal is user-defined.
  6. The direction of normals of elements selected as a panel for ERP output should be consistent. OptiStruct will automatically flip normals of elements which have inconsistent normals if such elements belong to panels selected for ERP output.