# NOLIN2

Bulk Data Entry Defines nonlinear transient forcing functions of the form.

(1)
${P}_{i}\left(t\right)=S\cdot {X}_{j}\left(t\right)\cdot {X}_{k}\left(t\right)$

Where, ${X}_{j}\left(t\right)$ and ${X}_{k}\left(t\right)$ can be either displacement or velocity at points GJ and GK, respectively, in the directions of CJ and CK, respectively.

## Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
NOLIN2 SID GI CI S GJ CJ GK CK

## Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
NOLIN2 14 2 1 2.9 2 1 2

## Definitions

Field Contents SI Unit Example
SID Nonlinear load set identification number.

No default (Integer > 0)

GI Grid or scalar point identification number at which nonlinear load is to be applied.

No default (Integer > 0)

CI Component number for GI.

No default (1 ≤ Integer ≤ 6; blank or 0, if GI is a scalar point)

S Scale factor.

No default(Real)

GJ, GK Grid or scalar point identification number.

No default (Integer > 0)

CJ, CK Component number for GJ, GK according to the following table:
Type Displacement Velocity
Grid 1 ≤ Integer ≤ 6 11 ≤ Integer ≤ 16
Scalar Blank or 0 Integer = 10

5. Nonlinear loads may be a function of displacement $\left(X=\stackrel{˙}{u}\right)$ or velocity $\left(X=\stackrel{˙}{u}\right)$ . Velocities are denoted by a component number ten greater than the actual component number; that is the component 11 indicates velocity in the 1 component direction. The velocity is determined by: (2)
${\stackrel{˙}{u}}_{t}=\frac{{u}_{t}-{u}_{t-1}}{\Delta t}$
$\Delta t$
${u}_{t-1}$