TLOAD1

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

Description

The load or enforced motion is of the form:(1)

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.

$A$ 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.

$F (t - τ)$ 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, RFORCE, QVOL, QBDY1, ACCEL, ACCEL1, ACCEL2, or GRAV entry set that defines { $A$ }. 2 3 (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 $F (t - τ)$ (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

Dynamic excitation sets must be selected with the Subcase Information command DLOAD=SID.

The type of dynamic excitation is specified by TYPE based on the following table:

TYPE		TYPE of Dynamic Excitation
Integer	Character	TYPE of Dynamic Excitation
0	L, LO, LOA, or LOAD	Applied load (force or moment) (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.

The TYPE also determines the manner in which EXCITEID is used by the program as:
- Excitation specified by TYPE is applied load. The EXCITEID must reference DAREA, FORCEx, MOMENTx, PLOAD, RFORCE, GRAV, QVOL, ACCEL, ACCEL1, ACCEL2 or QBDY1 entries.
- Excitation specified by TYPE is enforced motion. The EXCITEID must reference SPC/SPCD 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.
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.
SID must be unique for all TLOAD1, TLOAD2, RLOAD1, and RLOAD2 entries.
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.
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.
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) vs Load Scale Factors (Y) that scales the loading specified on the EXCITEID field.
The TSTIME field is only supported for Nonlinear subcases.
This card is represented as a load collector in HyperMesh.