TLOAD1

Bulk Data Entry Defines a time-dependent dynamic load or enforced motion.

Attention: Valid for Implicit and Explicit Analysis

Description

The load or enforced motion is of the form:

f ( t ) = A F ( t − τ )

For use in transient response analysis, transient heat transfer analysis, and to specify the user-defined static loading curve for Nonlinear Static Analysis.

Where,

f ( t ) is the time-dependent dynamic load or enforced motion, multiplier for transient heat transfer convection coefficient, or user-defined loading curve.

A MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGbbaaaa@399D@ defines the amplitude of the dynamic excitation in transient response analysis or base-load in Nonlinear static analysis and is referenced by the EXCITEID field.

F ( t − τ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVCI8FfYJH8YrFfeuY=Hhbbf9v8qqaqFr0xc9pk0xbb a9q8WqFfeaY=biLkVcLq=JHqpepeea0=as0Fb9pgeaYRXxe9vr0=vr 0=vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaiaadAeacaGGOa GaamiDaiabgkHiTiabes8a0jaacMcaaaa@3BBB@ is a user-defined function that defines the time-variant nature or loading scale factors for f ( t ) . It is specified by referencing a predefined TABLEDi entry in the TID field.

τ is the time delay defined in the DELAY field.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
TLOAD1 SID EXCITEID DELAY TYPE TID
"EXTN" TSTIME

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
TLOAD1 5 7 LOAD 13

Definitions

Field Contents SI Unit Example
SID Set identification number.

(Integer > 0)
EXCITEID Identification number of the DAREA, SPCD, FORCEx, MOMENTx, PLOADx, PLOADSF, PRSPENE, RFORCE, QVOL, QBDY1, ACCEL, ACCEL1, ACCEL2, GRAV, TEMP, TEMPD, or TEMPADD entry set that defines A MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGbbaaaa@399D@ . 2 3

When TYPE = 5, J, JO, JOU, or JOUL, this entry refers to the subcase identification number of a steady-state electrical analysis (SSEC).

When TYPE=EXT, the EXCITEID field refers to the ID of an ASSIGN,EXTLOD entry that identifies an .rsp/.rpc file for external loading.

(Integer > 0)
DELAY Defines time delay τ . If it is a non-zero integer, it represents the identification number of the DELAY Bulk Data Entry that defines τ . If it is real, then it directly defines the value of τ that will be used for all degrees-of-freedom that are excited by this dynamic load entry.

If blank or zero, τ will be zero.

(Integer ≥ 0, real or blank)
TYPE Defines the type of the dynamic excitation. 2 3

Default = 0 (Integer, character or blank)
TID TABLEDi or TABLEG entry identification number that gives F ( t − τ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVCI8FfYJH8YrFfeuY=Hhbbf9v8qqaqFr0xc9pk0xbb a9q8WqFfeaY=biLkVcLq=JHqpepeea0=as0Fb9pgeaYRXxe9vr0=vr 0=vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaiaadAeacaGGOa GaamiDaiabgkHiTiabes8a0jaacMcaaaa@3BBB@ .

(Integer > 0)
"EXTN" Extended options indicator.
TSTIME String to indicate Total/Subcase time switch. Only supported for Nonlinear subcases. 9
TOT or 0
Uses total time to look up table data for current TLOAD1.
SUB or 1
Uses subcase time to look up table data for current TLOAD1.
blank

Default = TOT

Comments

  1. Dynamic excitation sets must be selected with the Subcase Information command DLOAD=SID.
  2. The type of dynamic excitation is specified by TYPE based on the following table:
    TYPE TYPE of Dynamic Excitation
    Integer Character
    0 L, LO, LOA, or LOAD Applied load (force, moment or pressure)

    (Default)
    1 D, DI, DIS, or DISP Enforced displacement or temperature; EXCITEID references SPC/SPCD data.
    2 V, VE, VEL, or VELO Enforced velocity; EXCITEID references SPC/SPCD data.
    3 A, AC, ACC, or ACCE Enforced acceleration; EXCITEID references SPC/SPCD data.
    4 T, TE, TEM, or TEMP Enforced temperature; EXCITEID references TEMP/TEMPD/TEMPADD data.
    5 J, JO, JOU, or JOUL Enforced Joule loss density; EXCITEID references ID of a steady-state electrical subcase, from which the Joule loss density will be applied in the transient heat transfer subcase.
    - EXT External loading from an ASSIGN,EXTLOD entry referencing an .rsp/.rpc file.
  3. The TYPE also determines the manner in which EXCITEID is used by the program as:
    • If the excitation specified by TYPE is applied load, the EXCITEID must reference DAREA, FORCEx, MOMENTx, PLOADx, PLOADSF, PRSPENE, RFORCE, GRAV, QVOL, ACCEL, ACCEL1, ACCEL2 or QBDY1 entries.
    • If the excitation specified by TYPE is enforced motion (TYPE=1, 2, or 3), the EXCITEID must reference SPC/SPCD entries.
    • If the excitation specified by TYPE is enforced temperature (TYPE=4), the EXCITEID must reference TEMP/TEMPD/TEMPADD entries.
    • TYPE=1 must be specified if the EXCITEID field references SPCD data used in transient heat transfer analysis to define time-dependent thermal boundary conditions. This also applies when using SPCD to identify a time-dependent heat transfer convection coefficient.
  4. TLOAD1 loads may be combined with TLOAD2 loads only by specification on a DLOAD entry. That is, the SID on a TLOAD1 entry may not be the same as that on a TLOAD2 entry.
  5. SID must be unique for all TLOAD1, TLOAD2, RLOAD1, and RLOAD2 entries.
  6. If TLOAD1 entries are selected for Fourier analysis, then the time-dependent loads on the TLOAD1 entries are transformed to the frequency domain. Then the analysis is performed as a frequency response analysis, but the solution and the output are converted to and printed in the time domain.
  7. When EXCITEID refers to an SPCD entry, the modal space will be augmented with displacement vector(s) from linear static analysis with unit prescribed displacement at each of the SPCD degrees-of-freedom. EXCITEID cannot reference the LOAD and LOADADD Bulk Data Entries.
  8. The DT and TTERM fields on the NLPARM Bulk Data Entry allow for an alternate method (instead of NINC) to define the loading curve for Nonlinear Static Analysis. The DLOAD Subcase Entry can be used in a NLSTAT subcase to reference TLOAD1 Bulk Data Entry. This allows for the specification of a user-defined loading curve via the TID field on the TLOAD1 entry. The TID field references the Time (X) versus Load Scale Factors (Y) that scales the loading specified on the EXCITEID field.
  9. The TSTIME field is supported for nonlinear structural analysis, linear transient heat transfer, and nonlinear transient heat transfer analyses.
  10. RSP or RPC files can be used as loading for transient analysis; transient loading is set up internally using OptiStruct. The ASSIGN,EXTLOD entry can be used to identify the RSP or RPC file and mapping CSV file for external loading. Additionally, the ID of the ASSIGN entry can be referenced on a TLOAD1 entry in the transient analysis setup using the EXCITEID field. The TLOAD1 entry should have the TYPE field set to EXT to indicate the load is coming from an external file. Both direct and modal linear transient analyses are supported. The DELAY field on the TLOAD1 entry is supported for external loading (negative delay can be used to skip unnecessary data in the RSP or RPC file).
    Example: 
    ASSIGN,EXTLOD,102,’load.rsp’,’mapping.csv’
…
SUBCASE 1…
BEGIN BULK
…
TLOAD1,13,102,,EXT
  11. This card is represented as a load collector in HyperMesh.