DVLREL1

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

Format

To relate the Force value on grid 259 to Design Variable 5.

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)

The relationship between analysis model loading and design variable is:(1)
$L_{i} = C_{0} + \sum (C_{i}^{c o e f} * D V_{i})$
Where,

$L_{i}$

The designed load

$C_{0}$

The constant

$C_{i}^{c o e f}$

The coefficient

$D V_{i}$

The design variable
Multiple loads with the same set of SID, G, and, ATT2 reference are not allowed. OptiStruct will error out in such cases.
DVLREL1 and DVLREL2 entries are supported for Optimization based on Static Analysis only.