The default transient scheme for the nonlinear system is the same as that used for linear elasticity: the Newmark Method. The semi-discretized equation of transient motion for the nonlinear system is given as:
(16–30) |
Note that the internal load
is dependent on the current displacement
at time
. The linearized form of the previous equation can be obtained by the
Newton-Raphson method resulting in following equation:
(16–31) |
where | |
| |
| |
|
and
(16–32) |
(16–33) |
The same logic is extended to the Backward Euler scheme when used in conjunction with the Nonlinear Elasticity model.