NLENRG

Bulk Data Entry Defines parameters for energy variables printout for implicit nonlinear static and implicit nonlinear transient analyses.

Format

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NLENRG	`ID`	`PARAMi`	`VALUEi`

The following continuation line is optional and can be used to activate printout of energy variables for selected element SETs.

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
	“`ESET`”	`SET1`	`SET2`	etc.

The following continuation line is optional and can be used to activate printout of energy variables for selected contact interfaces.

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
	“`CONTACT`”	`CID1`	`CID2`	etc.

The following continuation line is optional and can be used to activate printout of energy variables for selected (per-property) groups of CGAP/CGAPG elements.

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
	“`PGAP`”	`PGID1`	`PGID2`	etc.

Example

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NLENRG	99	FREQ	2
	`ESET`	1001	1002
	`CONTACT`	ALL
	`PGAP`	100	200

Definitions

Field	Contents	SI Unit Example
`ID`	Each NLENRG Bulk Data Entry must have a unique ID. No default (Integer > 0)
`PARAMi`	Name of parameter.
`VALUEi`	Value of parameter.
`ESET`	Keyword indicating energy variables are to be printed for selected element SETs.
`SETi`	Element SET identification number. No default (Integer > 0)
`CONTACT`	Keyword indicating energy variables are to be printed for selected contact interfaces.
`CIDi`	ALL All the contact interfaces. Integer > 0 Contact interface identification number. No default
`PGAP`	Keyword indicating energy variables are to be printed for selected CGAP/CGAPG elements.
`PGIDi`	ALL All the PGAP properties. Integer > 0 PGAP property identification number. No default

PARAMi	VALUEi	SI Unit Example
`FREQ`	Output frequency in increments. Default = 1 (Integer > 0)
`HG`	Control for output of HyperGraph data files (*.nlm). 3 4 0 HyperGraph data output is not activated. 1 (Default) HyperGraph data output is activated for global energy variables. 2 HyperGraph data output is activated for the global energy variables and per-entity energy variables.

Comments

The NLENRG Bulk Data Entry is selected by the NLENRG Subcase Information command. In the following comments, filename implies the actual name of the input file or model.
The energy variables are printed into the filename_e.out file for all nonlinear subcases.
HyperGraph data file for the global energy variables, if activated is named as filename_s<n>_e.nlm for each nonlinear subcase; where, <n> denotes the subcase ID.
HyperGraph data file for the per-entity energy variables, if activated is named as for each entity in each nonlinear subcase:
- filename_eset<ID>_s<n>_e.nlm
- filename_cont<ID>_s<n>_e.nlm
- filename_pgap<ID>_s<n>_e.nlm
Where,

<ID>

Denotes the entity ID

<n>

Denotes the subcase ID

The files *.nlm can be read and plotted by HyperGraph and, a HyperGraph session file named filename_nlm.mvw is created for straightforward plotting of the global energy variables.
For an implicit nonlinear subcase, if NLENRG entry is not defined, the global energy variables are written into a HyperGraph data file (filename_s<n>_e.nlm) for each time increment. However, the output of the filename_e.out file requires the presence of NLENRG Bulk/Subcase Entry pair.
The global energy variables include:
- • Total strain energy
  - Plastic dissipation energy
  - Hourglass energy
- Static stabilization energy
- Contact stabilization energy
The element energy variables include:
- • Total strain energy
  - Plastic dissipation energy
  - Hourglass energy
- Static stabilization energy
The contact/gap energy variables include:
- Contact stabilization energy
Implicit nonlinear analysis does not support hourglass elements and so hourglass energy is always zero.
Energy output for implicit nonlinear analysis is only controlled by the NLENRG Bulk/Subcase Entry pair. There is no influence of NLMON or NLOUT entries on the nonlinear energy output. Additionally, energy is always output on-the-fly dynamically during the analysis.