DVLREL1

Bulk Data Entry Linearly relates a design variable to an analysis model element.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
DVLREL1 ID TYPE SID LNAME     C0    
  ATT1 ATT2              
  DVID1 COEF1 DVID2 COEF2 etc.        

Example

To relate the Force value on grid 259 to Design Variable 5.
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
DVLREL1 88 FORCE 1 F     0.0    
  259 1              
  5 1              
DESVAR 5 5.00 1.50 9.90          

Definitions

Field Contents SI Unit Example
ID Relationship identification number. ID must be unique with respect to other DVLREL1 cards.

No default (Integer > 0)

 
TYPE Loading type.
FORCE
Indicates that the designed load references a FORCE entry.
MOMENT
Indicates that the designed load references a MOMENT entry.

No default

 
SID Identification number of a FORCE or MOMENT Bulk Data Entry. This selection depends on the value of the TYPE field.

No default (Integer > 0)

 
LNAME Load identifier.
F
Load vector
N1/N2/N3
Load Vector in N1/N2/N3 directions

No default

 
C0 Constant in the design variable and load relationship equation.

Default = 0.0 (Real)

 
ATT1 Identifies the grid point at which the designed load is applied.

No default (Integer > 0)

 
ATT2 Identifies the coordinate system for the designed load reference.

No default (Integer > 0)

 
DVIDi DESVAR identification number.

No default (Integer > 0)

 
COEFi Coefficient in design variable and load relationship equation.

Default = 1.0 (Real)

 

Comments

  1. The relationship between analysis model loading and design variable is:(1)
    L i = C 0 + ( C i c o e f * D V i )
    Where,
    L i
    The designed load
    C 0
    The constant
    C i c o e f
    The coefficient
    D V i
    The design variable
  2. Multiple loads with the same set of SID, G, and, ATT2 reference are not allowed. OptiStruct will error out in such cases.
  3. DVLREL1 and DVLREL2 entries are supported for Optimization based on Static Analysis only.