Basics : Internal 3D flow
This LS-DYNA simulation shows a simple 3D ICFD problem. It features a flow through a cylindrical pipe. Since the Reynolds number is laminar, a parabolic profile is expected at the outlet. It makes use of the ICFD_CONTROL_SURFMESH keyword to remesh the original surface mesh. The purpose of the ICFD_CONTROL_MESH in this input deck is to add more elements through the cylinder's diameter. It is also a good example for the MESH_BL_SYM keyword. The user can comment that keyword to see its impact on the mesh close to the inlet or outlet.
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Basics : Internal 3D flow
This LS-DYNA simulation shows a simple 3D ICFD problem. It features a flow through a cylindrical pipe. Since the Reynolds number is laminar, a parabolic profile is expected at the outlet. It makes use of the ICFD_CONTROL_SURFMESH keyword to remesh the original surface mesh. The purpose of the ICFD_CONTROL_MESH in this input deck is to add more elements through the cylinder's diameter. It is also a good example for the MESH_BL_SYM keyword. The user can comment that keyword to see its impact on the mesh close to the inlet or outlet.
*DATABASE_BINARY_D3PLOT *DEFINE_CURVE_TITLE *END *ICFD_BOUNDARY_FREESLIP *ICFD_BOUNDARY_PRESCRIBED_VEL *ICFD_BOUNDARY_PRESCRIBED_PRE *ICFD_BOUNDARY_NONSLIP *ICFD_CONTROL_MESH *ICFD_CONTROL_TIME *ICFD_CONTROL_SURFMESH *ICFD_DATABASE_FLUX *ICFD_MAT *ICFD_PART *ICFD_PART_VOL *ICFD_SECTION *INCLUDE *KEYWORD *MESH_BL *MESH_BL_SYM *MESH_SURFACE_ELEMENT *MESH_SURFACE_NODE *MESH_VOLUME *PARAMETER *TITLE
$-----------------------------------------------------------------------------
$
$ 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 R8.0.0 (or higher) with double precision
$X
$X------------------------------------------------------------------------------
$# UNITS: Dimensionless.
$X------------------------------------------------------------------------------
$X
*keyword
*title
ICFD 3D Internal flow
*include
mesh.k
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ PARAMETERS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*PARAMETER
R T_end 10.0
R dt_plot 1.00
$
$--- Fluid
$
R v_inlet 1.0
Rrho_fluid 1.0
R mu_fluid 0.005
R dt_fluid 0.050
$
$---+----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_SURFMESH
$# rsrf
1
*ICFD_CONTROL_MESH
$# mgsf
1.1
$---+----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_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_VOL
$# pid secid mid
10 1 1
$# spid1 spid2 spid3
1 2 3
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ ICFD BOUNDARY/INITIAL CONDITIONS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_BOUNDARY_PRESCRIBED_VEL
$# pid dof vad lcid
1 1 1 1
*ICFD_BOUNDARY_PRESCRIBED_VEL
$# pid dof vad lcid
1 2 1 2
*ICFD_BOUNDARY_PRESCRIBED_PRE
$# pid lcid sf death birth
2 2
*ICFD_BOUNDARY_NONSLIP
$# pid
3
*DEFINE_CURVE_TITLE
Velocity inlet
$# lcid sidr sfa sfo offa offo dattyp
1 &v_inlet
$# a1 o1
0.0 1.0
10000.0 1.0
*DEFINE_CURVE_TITLE
Pressure outlet
$# lcid sidr sfa sfo offa offo dattyp
2
$# a1 o1
0.0 0.0
10000.0 0.0
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ ICFD MESH KEYWORDS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*MESH_VOLUME
$# volid
1
$# pid1 pid2 pid3 pid4
1 2 3
*MESH_BL
$# pid nelth
3 1
*MESH_BL_SYM
$# pid1
1
*MESH_BL_SYM
$# pid1
2
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ DATABASE (OUTPUT) $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_DATABASE_FLUX
$# pid
2
*DATABASE_BINARY_D3PLOT
&dt_plot
*END
Fluid velocity fringes
This LS-DYNA simulation shows a simple 3D ICFD problem. It features a flow through a cylindrical pipe. Since the Reynolds number is laminar, a parabolic profile is expected at the outlet. It makes use of the ICFD_CONTROL_SURFMESH keyword to remesh the original surface mesh. The purpose of the ICFD_CONTROL_MESH keyword is to have more elements through the cylinder's diameter. It is also a good example for the MESH_BL_SYM keyword. The user can comment that keyword to see its impact on the mesh close to the inlet or outlet.