Advanced: Fluid Elastic Body Interaction — Welcome to LS-DYNA Examples

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This case is an extensive benchmark problem featuring a rolling tank with an elastic plate in between. The oscillations of the plate are studied. Due to the extensive computational time required in order to study this problem, it is frequently presented in 2D. However, the version offered here is in 3D, highlighting the powerful capabilities of the solver in handling mesh movement and remeshing as well as strong coupling fluid structure interaction. 32 CPUs or more are recommended in order to run this problem.

Animated Result

Fluid pressure fringes

Keywords

```*KEYWORD
*TITLE
*BOUNDARY_PRESCRIBED_MOTION_RIGID
*CONTROL_IMPLICIT_DYNAMICS
*CONTROL_IMPLICIT_GENERAL
*CONTROL_IMPLICIT_SOLUTION
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DEFINE_CURVE
*DEFINE_CURVE
*DEFINE_VECTOR
*ELEMENT_SOLID
*INCLUDE
*ICFD_BOUNDARY_FSI
*ICFD_BOUNDARY_FREESLIP
*ICFD_BOUNDARY_NONSLIP
*ICFD_CONTROL_FSI
*ICFD_CONTROL_TIME
*ICFD_CONTROL_OUTPUT
*ICFD_DATABASE_DRAG
*ICFD_MAT
*ICFD_SECTION
*ICFD_PART
*ICFD_PART
*ICFD_PART
*ICFD_PART
*ICFD_PART
*ICFD_PART
*ICFD_PART
*ICFD_PART_VOL
*MAT_ELASTIC
*MAT_RIGID
*MESH_INTERF
*MESH_VOLUME
*MESH_SURFACE_NODE
*MESH_SURFACE_ELEMENT
*NODE
*PART_INERTIA
*PART
*SECTION_SOLID
*END```

Reduced Input

```\$-----------------------------------------------------------------------------
\$
\$ Example provided by Iñaki (LSTC)
\$
\$ E-Mail: info@dynamore.de
\$ Web: http://www.dynamore.de
\$
\$ Copying for non-commercial usage allowed if
\$ copy bears this notice completely.
\$
\$X------------------------------------------------------------------------------
\$X
\$X 1. Run file as is.
\$X    Requires LS-DYNA MPP R9 (or higher) with double precision
\$X
\$X------------------------------------------------------------------------------
\$# UNITS: (kg/m/s)
\$X------------------------------------------------------------------------------
\$X
*KEYWORD
*TITLE
ICFD Fluid Elastic Body Interaction
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
\$                                                                              \$
\$                             PARAMETERS                                       \$
\$                                                                              \$
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*PARAMETER
R    T_end       10.
R  dt_plot      0.05
\$
\$--- Fluid
\$
Rrho_fluid      917.
R mu_fluid      0.05
R dt_fluid        0.
R dt_min      2.5e-3
R dt_max      5.0e-3
R  grav         9.81
R  fsi_bt       1e-3
*INCLUDE
mesh.k
*INCLUDE
struc.k
*INCLUDE
clamped_beam_mid_depth_oil.k
\$===============================================================================
\$                                                                              \$
\$                            F L U I D   P R O B L E M                         \$
\$                                                                              \$
\$===============================================================================
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
\$                                                                              \$
\$                           ICFD CONTROL CARDS                                 \$
\$                                                                              \$
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_CONTROL_TIME
\$#     ttm        dt       cfl    lcidsf     dtmin     dtmax
&T_end &dt_fluid                       &dt_min   &dt_max
*ICFD_CONTROL_FSI
\$#     owc        bt
0
*ICFD_CONTROL_OUTPUT
\$#   msglv
3
*ICFD_CONTROL_MESH
\$#    mgsf
1.05
*ICFD_CONTROL_IMPOSED_MOVE
\$#     pid
2
\$#  alphal
100
\$#    ptid
1
*ICFD_CONTROL_IMPOSED_MOVE
\$#     pid
3
\$#  alphal
100
\$#    ptid
1
*ICFD_CONTROL_IMPOSED_MOVE
\$#     pid
4
\$#  alphal
100
\$#    ptid
1
*ICFD_CONTROL_IMPOSED_MOVE
\$#     pid
8
\$#  alphal
100
\$#    ptid
1
*ICFD_CONTROL_IMPOSED_MOVE
\$#     pid
9
\$#  alphal
100
\$#    ptid
1
*ICFD_CONTROL_IMPOSED_MOVE
\$#     pid
10
\$#  alphal
100
\$#    ptid
1
*ICFD_DEFINE_POINT
\$#    poid         x         y         z
1         0         0         0
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
\$                                                                              \$
\$                       ICFD PARTS/ SECTION/ MATERIAL                          \$
\$                                                                              \$
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_SECTION
\$#     sid
1
*ICFD_MAT
\$#     mid       flg        ro       vis
1         1&rho_fluid &mu_fluid
*ICFD_MAT
\$#     mid       flg
2         0
*ICFD_PART
\$#     pid     secid       mid
1         1         1
*ICFD_PART
\$#     pid     secid       mid
2         1         1
*ICFD_PART
\$#     pid     secid       mid
3         1         1
*ICFD_PART
\$#     pid     secid       mid
4         1         1
*ICFD_PART
\$#     pid     secid       mid
6         1         1
*ICFD_PART
\$#     pid     secid       mid
7         1         2
*ICFD_PART
\$#     pid     secid       mid
8         1         2
*ICFD_PART
\$#     pid     secid       mid
9         1         2
*ICFD_PART
\$#     pid     secid       mid
10         1         2
*ICFD_PART_VOL
\$#     pid     secid       mid
11         1         1
\$#   spid1     spid2     spid3     spid4     spid5
6         7         8         9        10
*ICFD_PART_VOL
\$#     pid     secid       mid
12         1         2
\$#   spid1     spid2     spid3     spid4     spid5
1         2         3         4         6
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
\$                                                                              \$
\$                                                                              \$
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_BOUNDARY_NONSLIP
\$#     pid
1
*ICFD_BOUNDARY_NONSLIP
\$#     pid
2
*ICFD_BOUNDARY_NONSLIP
\$#     pid
3
*ICFD_BOUNDARY_NONSLIP
\$#     pid
4
*ICFD_BOUNDARY_NONSLIP
\$#     pid
7
*ICFD_BOUNDARY_NONSLIP
\$#     pid
8
*ICFD_BOUNDARY_NONSLIP
\$#     pid
9
*ICFD_BOUNDARY_NONSLIP
\$#     pid
10
*ICFD_BOUNDARY_FSI
\$#     pid
1
*ICFD_BOUNDARY_FSI
\$#     pid
7
\$#    lcid        sf
1        1
*DEFINE_CURVE_TITLE
Gravity force
\$#    lcid      sidr       sfa       sfo      offa      offo    dattyp
1                    &grav
\$#                a1                  o1
0.0                 1.0
10000.0                 1.0
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
\$                                                                              \$
\$                            ICFD MESH KEYWORDS                                \$
\$                                                                              \$
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*MESH_VOLUME
\$#   volid
30
\$#    pid1      pid2      pid3      pid4      pid5      pid6      pid7      pid8
1         2         3         4         7         8         9        10
*MESH_INTERF
\$#   volid
30
\$#    pid1
6
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
\$                                                                              \$
\$                             DATABASE (OUTPUT)                                \$
\$                                                                              \$
\$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_DATABASE_DRAG
\$#     pid
1
*ICFD_DATABASE_DRAG
\$#     pid
7
*DATABASE_BINARY_D3PLOT
&dt_plot
*END```

Description

This case is an extensive benchmark problem featuring a rolling tank with an elastic plate in between. The oscillations of the plate are studied. Due to the extensive computational time required in order to study this problem, it is frequently presented in 2D. However, the version offered here is in 3D, highlighting the powerful capabilities of the solver in handling mesh movement and remeshing as well as strong coupling fluid structure interaction. 32 CPUs or more are recommended in order to run this problem.

References :

[1] S. Idelsohn, J. Marti, A. Souto-Iglesias, and E. Onate, “Interaction between an elastic structure and free-surface flows: experimental versus numerical comparisons using the PFEM,” Computational Mechanics, vol. 43, no. 1, pp. 125–132, December 2008.

[2] J. Degroote, A. Souto-Iglesias, W. V. Paepegem, S. Annerel, P. Bruggeman, and J. Vierendeels, “Partitioned simulation of the interaction between an elastic structure and free surface flow,” Computer Methods in Applied Mechanics and Engineering, (in press).

[3] Botia-Vera, E., A. Souto-Iglesias, G. Bulian, and L. Lobovský (2010). Three SPH Novel Benchmark Test Cases for free surface flows. In 5th ERCOFTAC SPHERIC workshop on SPH applications.