ACCLR
Bulk Data Entry Defines accelerometer for geometric nonlinear analysis.
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
ACCLR | AID | GID | FCUT |
Example
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
ACCLR | 100 | 34 | 100.0 |
Definitions
Field | Contents | SI Unit Example |
---|---|---|
AID | Unique accelerometer
identification number. (Integer > 0) |
|
GID | Grid point identification
number. (Integer > 0) |
|
FCUT | Cutoff frequency. (Real > 0) |
Comments
- The accelerometer option computes a filtered acceleration in the output system.
- These filtered accelerations provided by an accelerometer are used in either a SENSOR or in post-processing acceleration time history without aliasing problems.
- A 4-pole Butterworth filter is used.
- The recommended value for FCUT is 1650 Hz (1.65 ms-1) to obtain a class 1000 SAE filtering.
- In addition to these filtered accelerations, the accelerometer also allows the output of the integrals of X, Y, and Z of the raw accelerations projected to the output coordinate system to time history. These quantities are not used by SENSOR.
- If the coordinates are moving, the integrals of X, Y, and Z raw accelerations projected to the output coordinate system are not the same as the velocities projected to the output coordinate system, as described in XHIST. Computation of these integrals in a post-processor allows retrieving the accelerations projected to the output coordinate system without aliasing problems. Integration and differentiation are acting like another filter on top of the 4-pole Butterworth.
- This card is unsupported in HyperMesh.