Intermediate : Sinking Sphere
In this FSI example, a solid sphere with a density close to water is allowed to freely sink. Remeshing is triggered and the the finer mesh zone follows the sphere's displacements.
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Intermediate : Sinking Sphere
In this FSI example, a solid sphere with a density close to water is allowed to freely sink. Remeshing is triggered and the the finer mesh zone follows the sphere's displacements.
Fluid velocity fringes
*KEYWORD *TITLE *DATABASE_BINARY_D3PLOT *DEFINE_CURVE_TITLE *CONTROL_IMPLICIT_GENERAL *CONTROL_IMPLICIT_DYNAMICS *CONTROL_TERMINATION *ICFD_BOUNDARY_FREESLIP *ICFD_BOUNDARY_FSI *ICFD_BOUNDARY_NONSLIP *ICFD_CONTROL_FSI *ICFD_CONTROL_OUTPUT *ICFD_CONTROL_TIME *ICFD_DEFINE_POINT *ICFD_MAT *ICFD_PART *ICFD_PART_VOL *ICFD_SECTION *INCLUDE *LOAD_BODY_Y *MAT_RIGID *MESH_BL *MESH_INTERF *MESH_SIZE_SHAPE *MESH_SURFACE_ELEMENT *MESH_SURFACE_NODE *MESH_VOLUME *NODE *PARAMETER *PART *SECTION *END
$-----------------------------------------------------------------------------
$
$ Example provided by Iñaki (LSTC)
$
$ E-Mail: info@dynamore.de
$ Web: http://www.dynamore.de
$
$ Copyright, 2015 DYNAmore GmbH
$ 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 Dev 121000 (or higher) with double precision
$X
$X------------------------------------------------------------------------------
$# UNITS: (kg/m/s)
$X------------------------------------------------------------------------------
$X
*KEYWORD
*TITLE
ICFD Sphere sinking
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ PARAMETERS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*PARAMETER
R T_end 0.2
R dt_plot 5e-3
$
$--- Fluid
$
Rrho_fluid 1000
R mu_fluid 0.001
R dt_fluid 5e-4
R grav 9.81
$
$--- Struc
$
Rrho_struc 2540.
RE_struc 2e11
Rnu_struc 0.3
*INCLUDE
mesh.k
*INCLUDE
struc.k
*DATABASE_BINARY_D3PLOT
&dt_plot
$
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ ICFD CONTROL CARDS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_CONTROL_TIME
$# ttm dt
&T_end &dt_fluid
*ICFD_CONTROL_FSI
$# owc bt
0
*ICFD_CONTROL_OUTPUT
$# msglv
3
*ICFD_CONTROL_ADAPT_SIZE
$# asize
1 20
$---+----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 ro vis
2 0
*ICFD_PART
$# pid secid mid
1 1 2
*ICFD_PART
$# pid secid mid
2 1 2
*ICFD_PART
$# pid secid mid
3 1 2
*ICFD_PART
$# pid secid mid
4 1 1
*ICFD_PART
$# pid secid mid
5 1 1
*ICFD_PART
$# pid secid mid
6 1 1
*ICFD_PART
$# pid secid mid
7 1 1
*ICFD_PART_VOL
$# pid secid mid
8 1 2
$# spid1 spid2 spid3 spid4 spid5 spid6 spid7 spid8
1 2 3 4
*ICFD_PART_VOL
$# pid secid mid
16 1 1
$# spid1 spid2 spid3 spid4 spid5 spid6 spid7 spid8
4 5 6 7
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ ICFD BOUNDARY/INITIAL CONDITIONS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_BOUNDARY_FSI
$# pid
1
*ICFD_BOUNDARY_FSI
$# pid
5
*ICFD_BOUNDARY_NONSLIP
$# pid
1
*ICFD_BOUNDARY_NONSLIP
$# pid
5
*ICFD_BOUNDARY_FREESLIP
$# pid
2
*ICFD_BOUNDARY_FREESLIP
$# pid
3
*ICFD_BOUNDARY_FREESLIP
$# pid
6
*ICFD_BOUNDARY_FREESLIP
$# pid
7
*LOAD_BODY_Y
$# 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 5 6 7
*MESH_INTERF
$# pid
30
$# spid1
4
*MESH_BL
1 1
*MESH_BL
5 1
*MESH_SIZE_SHAPE
sphere,1,1
0.00025 0.01 3
*ICFD_DEFINE_POINT
1 0 0 0 1
*END
In this FSI example, a solid sphere with a density close to water is allowed to freely sink. Remeshing is triggered and the the finer mesh zone follows the sphere's displacements. Results can be compared to experiments.
References :
[1] : A Smooth Particle Hydrodynamics discretization for the modelling of free surface flows and rigid body dynamics. Ricardo B. Canelas. Jose M. Domínguez, Alejandro J.C. Crespo, Moncho Gómez-Gesteira and Rui M.L. Ferreira