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*DYNAMIC
Data format:
A single line with 5 parameters, as follows:
TINI TFIN DT INTEG IOPDYN
Status:
Required (dynamics and external forces computation).
Purpose:
To define simulation control parameter or times of external forces computation
Details :
| Parameter | Description |
|---|---|
| TINI | Initial time of the dynamic simulation, in seconds. Defaults to 0. |
| TFIN | Final time of the dynamic simulation, in seconds.. |
| DT | Default time step in seconds. |
| INTEG | Flag for the choice of a time integrator : INTEG = 7 : Newmark implicit integration scheme. |
| IOPTDYN | Predictor: IOPDYN = 0: IFPEN Newmark's method (with numerical damping) IOPDYN = 1: Newmark's method IOPDYN = 2: Initial values X(t+dt) are computed value at X(t) [X : position vector of the nodes] IOPDYN = 3: Initial values X(t+dt) are computed value at X(t+dt)=X(t)+V(t).dt [V : Velocity vector of the nodes] IOPDYN = 4: Initial values X(t+dt) are computed value at X(t+dt)=X(t)+V(t).dt+0.5*A(t).dt.dt [A : Acceleration vector of the nodes] Defaults to 0. |
Note
-
This keyword triggers a dynamic calculation.
-
TINI is 0.
When TINI = 0. a static or quasi-static analysis is performed before the dynamic simulation.
-
The time step is automatically adjusted during the simulation if you use IOPTDT = 1 in *DYNIMP.
-
The duration of the simulation is TFIN-TINI : when dealing with periodic excitations it is recommended to perform the computation during at least 3 periods to eliminate the transient response.
Example:
*DYNAMIC
1. 60 0.1 7 0
A simulation from 0. to 60. seconds is asked for, with an starting time step of 0.1 s time. Newmark's integrator is chosen, IFP version. This is equivalent to
*DYNAMIC
0. 60. 0.1
