Damping
A cantilever beam is subjected to a load at the free end. The beam then vibrates relative to the equilibrium position without damping in case 1 and with damping in case 2.
https://www.dynaexamples.com/introduction/examples-manual/control/damping
https://www.dynaexamples.com/@@site-logo/LS-DYNA-Examples-Logo480x80.png
Damping
A cantilever beam is subjected to a load at the free end. The beam then vibrates relative to the equilibrium position without damping in case 1 and with damping in case 2.
*CONTROL_DAMPING Cantilever Beam LS-DYNA Manual Section: *CONTROL_DAMPING Additional Sections: *DAMPING_GLOBAL *DATABASE_CROSS_SECTION_SET *LOAD_NODE_SET Example: Cantilever Beam Filename: control_damping.beam.k Description: A cantilever beam is subjected to a load at the free end. The beam then vibrates relative to the equilibrium position without damping in case 1 and with damping in case 2. Model: The beam me asures 1000 * 100 * 10 mm3 and is modeled by 10 Belytschko-Tsay shell elements. A force of 100 N is applied in the z -direction at the free end. The calculation ends at 0.5 seconds. Input for the undamped system: The force at the free end is applied as two point forces. The size of these forces is controlled by load curve d efinition number 1 (*DEF INE_CURVE, * LOAD_NODE_SET). The ASCII-files contain information for section forc data, nodal information, and shell element information. Data from ASCII-files can be processed in phase 3 of LS-TAURUS. Input for the damped system: The same input as in the undamped cas e except for a global damping constant (*DAMPING_GLOBAL, *CONTROL_DAMPING). Reference: Schweizerhof, K. and Weimar, K.
$*DAMPING_GLOBAL *CONTROL_CONTACT *CONTROL_DYNAMIC_RELAXATION *CONTROL_ENERGY *CONTROL_HOURGLASS *CONTROL_OUTPUT *CONTROL_TERMINATION *DAMPING_GLOBAL *DATABASE_BINARY_D3PLOT *DATABASE_BINARY_D3THDT *DATABASE_CROSS_SECTION_SET *DATABASE_ELOUT *DATABASE_EXTENT_BINARY *DATABASE_GLSTAT *DATABASE_HISTORY_NODE *DATABASE_HISTORY_SHELL *DATABASE_NODOUT *DATABASE_SECFORC *DEFINE_CURVE *ELEMENT_SHELL *END *KEYWORD *LOAD_NODE_SET *MAT_ELASTIC *NODE *PART *SECTION_SHELL *SET_NODE_LIST *SET_SHELL_LIST *TITLE
*KEYWORD
*TITLE
Cantilever Beam with Damping
$
$ LSTC Example
$
$ Last Modified: September 11, 1997
$
$ Units: ton, mm, s, N, MPa, N-mm
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Damping
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*DAMPING_GLOBAL
$ lcid valdmp
0 0.0
$
$$$$ for damping of 10
$
$*DAMPING_GLOBAL
$ 0 10.0
$
$$$$ for damping of 50
$
$*DAMPING_GLOBAL
$ 0 50.0
$
*CONTROL_DYNAMIC_RELAXATION
$ nrcyck drtol drfctr drterm tssfdr irelal edttl idrflg
100 1.0e-3 0.995 0.9
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Control Ouput
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*CONTROL_TERMINATION
$ endtim endcyc dtmin endneg endmas
0.5001
$
*CONTROL_CONTACT
$ slsfac rwpnal islchk shlthk penopt thkchg orien
0.1
$ usrstr usrfac nsbcs interm xpenen
$
*CONTROL_ENERGY
$ hgen rwen slnten rylen
2 2
$
*CONTROL_HOURGLASS
$ ihq qh
4
$
*CONTROL_OUTPUT
$ npopt neecho nrefup iaccop opifs ipnint ikedit
0 0 0 0 2 1000
$
*DATABASE_EXTENT_BINARY
$ neiph neips maxint strflg sigflg epsflg rltflg engflg
1
$ cmpflg ieverp beamip
$
*DATABASE_BINARY_D3PLOT
$ dt lcdt
0.020
$
*DATABASE_BINARY_D3THDT
$ dt lcdt
999999
$
*DATABASE_ELOUT
$ dt
0.001
$
*DATABASE_HISTORY_SHELL
$ id1 id2 id3 id4 id5 id6 id7 id8
1
$
*DATABASE_GLSTAT
$ dt
0.001
$
*DATABASE_NODOUT
$ dt
0.001
$
*DATABASE_HISTORY_NODE
$ id1 id2 id3 id4 id5 id6 id7 id8
21
$
*DATABASE_SECFORC
$ dt
0.001
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Cross Sections
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$$ define a cross section through the beam to monitor force & moment
$
*DATABASE_CROSS_SECTION_SET
$ nsid hsid bsid ssid tsid dsid
1 1
$
*SET_NODE_LIST
$ sid da1 da2 da3 da4
1
$ nid1 nid2 nid3 nid4 nid5 nid6 nid7 nid8
1 2
$
*SET_SHELL_LIST
$ sid da1 da2 da3 da4
1
$ eid1
1
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Loading
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Load nodes 21 and 22 with a constant 50 N in the z-direction.
$
*LOAD_NODE_SET
$ nsid dof lcid sf cid m1 m2 m3
2 3 1 0.5
$
*SET_NODE_LIST
$ sid da1 da2 da3 da4
2
$ nid1 nid2 nid3 nid4 nid5 nid6 nid7 nid8
21 22
$
*DEFINE_CURVE
$ lcid sidr scla sclo offa offo
1
$ a o
0.0 100.0
10.0 100.0
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Parts and Materials
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*PART
$ pid sid mid eosid hgid adpopt
Beam - Elastic Material
1 1 1
$
$
*MAT_ELASTIC
$ mid ro e pr da db k
1 1.00e-08 210000.0 0.300
$
$
*SECTION_SHELL
$ sid elform shrf nip propt qr/irid icomp
1 2 1.0 2 1.0
$ t1 t2 t3 t4 nloc
10.0 10.0 10.0 10.0 0.0
$
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Nodes and Elements
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Nodes 1 and 2 have fixed boundary conditions (translation and rotation).
$
$
*END