FATEVNT

Bulk Data Entry Defines loading events for Fatigue Analysis.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
FATEVNT ID FLOAD1 FLOAD2 FLOAD3 FLOAD4 FLOAD5 FLOAD6 FLOAD7
FLOAD8 etc. etc. SQNTL

Definitions

Field Contents SI Unit Example
ID Each FATEVNT card must have a unique ID. This identifier may be referenced by a FATSEQ definition.

No default (Integer > 0)
FLOAD# A FATLOAD entry identification number. 1 3

No default (Integer > 0)
SQNTL Flag to switch applied FATLOAD’s to sequential loading.
SQNTL
If present at the end of the FLOAD# list, then the FATLOAD’s are applied sequentially as if the individual loads are separate time steps. The location of this field is not fixed; this flag can be specified in the field next to the final FLOAD#.
If SQNTL flag is present, the TID field on the corresponding FATLOAD entries should be blank. 5
Blank (Default)
The FATLOAD’s are not applied sequentially and are superimposed. This is the default behavior.

Comments

  1. FATLOAD entries referenced on this Bulk Data Entry may reference different subcases.
  2. Identification numbers of FATSEQ and FATEVNT share the same ID pool.
  3. Typically, the referenced FATLOAD entries can reference only the same subcase type on the same FATEVNT entry. Referencing a combination of subcase types using FATLOAD entries on the same FATEVNT entry is typically not allowed, except for the following applications:
    • Sine-on-Random Fatigue Analysis: On the same FATEVNT, referenced FATLOADs can point to random response subcase and frequency response subcase.
    • Sine-Sweep on Random Fatigue Analysis: On the same FATEVNT, referenced FATLOADs can point to random response subcase and frequency response subcase.
    • Linear Static Analysis, Nonlinear Static Analysis, Linear Transient Analysis, Nonlinear Transient Analysis: On the same FATEVNT, referenced FATLOADs can point to static subcases and transient subcases. In this case, the FATLOAD referring to the static subcase should not reference a TABFAT entry. Multiple static subcases (via corresponding FATLOADs) and multiple transient subcases (via corresponding FATLOADs) can be specified on the same FATEVNT entry as well. The FATLOADs coming from multiple static subcases are linearly superimposed. The LDM field on FATLOADs of such static subcases can be used to modify the stress. This is supported for all fatigue solutions supported by both direct and modal transient analysis (SN, EN, Spot Weld Fatigue, and Dang Van Fatigue).
  4. In solder fatigue, only one FATLOAD entry is allowed.
  5. SQNTL field is only supported for Fatigue with Static Analysis. When SQNTL is not present, for all FATLOADs referenced in FATEVNT, the load histories from corresponding TABFATs are used to determine stress histories for each FATLOAD and are subsequently superimposed to generate the final stress history for each fatigue event. If the SQNTL flag is present, the TID field on the corresponding FATLOAD entries should be blank. Each FATLOAD now will directly be considered as a point in the final stress history.
  6. This card is represented as a load collector in HyperMesh.