Basics : Turbulent flow
This LS-DYNA simulation shows a turbulent flow input deck. The fluid and boundary conditions give a Reynolds number of 50 000 making the flow turbulent and prompting the use of a turbulence model. The default configuration uses a RANS realizable model. The boundary layer mesh has been chosen in accordance, to yield an approximate Y+ value of 30. Several other turbulence models can be tried and the boundary layer mesh changed accordingly. The user can study the length and effects of the recirculation zone over the thick plate.
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Basics : Turbulent flow
This LS-DYNA simulation shows a turbulent flow input deck. The fluid and boundary conditions give a Reynolds number of 50 000 making the flow turbulent and prompting the use of a turbulence model. The default configuration uses a RANS realizable model. The boundary layer mesh has been chosen in accordance, to yield an approximate Y+ value of 30. Several other turbulence models can be tried and the boundary layer mesh changed accordingly. The user can study the length and effects of the recirculation zone over the thick plate.
This LS-DYNA simulation shows a turbulent flow input deck. The fluid and boundary conditions give a Reynolds number of 50 000 making the flow turbulent and prompting the use of a turbulence model. The default configuration uses a RANS realizable model. The boundary layer mesh has been chosen in accordance, to yield an approximate Y+ value of 30. Several other turbulence models can be tried and the boundary layer mesh changed accordingly. The user can study the length and effects of the recirculation zone over the thick plate.
Turbulent intensity fringes
*DATABASE_BINARY_D3PLOT *KEYWORD *TITLE *DEFINE_CURVE_TITLE *ICFD_BOUNDARY_FREESLIP *ICFD_BOUNDARY_PRESCRIBED_PRE *ICFD_BOUNDARY_PRESCRIBED_VEL *ICFD_BOUNDARY_PRESCRIBED_TURBULENCE *ICFD_BOUNDARY_NONSLIP *ICFD_CONTROL_OUTPUT *ICFD_CONTROL_TAVERAGE *ICFD_CONTROL_TIME *ICFD_CONTROL_TURBULENCE *ICFD_DATABASE_DRAG *ICFD_DATABASE_TIMESTEP *ICFD_INITIAL *ICFD_MAT *ICFD_PART *ICFD_PART_VOL *ICFD_SECTION *INCLUDE *MESH_BL *MESH_SURFACE_ELEMENT *MESH_SURFACE_NODE *MESH_VOLUME *PARAMETER *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 R9.0.0 (or higher) with double precision
$X
$X------------------------------------------------------------------------------
$# UNITS: (kg/m/s)
$X------------------------------------------------------------------------------
$X
*KEYWORD
*TITLE
ICFD Turbulent thick plate
*INCLUDE
mesh.k
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ PARAMETERS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*PARAMETER
R T_end 2.0
R dt_plot 0.05
$
$--- Fluid
$
R v_inlet 8.33
Rrho_fluid 1.22500
R mu_fluid 1.7895e-5
R dt_fluid 1e-4
R mu_turb 1e4
$
$---+----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_TURBULENCE
$ RANS realizable k-epsilon
$# tmod submcd wlaw
1 2 1
$ LES Smagorinsky
$2
$ RANS Menter-SST
$4,3
*ICFD_CONTROL_TAVERAGE
$# dt
1
*ICFD_CONTROL_OUTPUT
$# mslv
3
*ICFD_CONTROL_MESH
$# mgsf mstrat 2dstruc
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
$# pid secid mid
4 1 1
*ICFD_PART_VOL
$# pid secid mid
10 1 1
$# spid1 spid2 spid3 spid4
1 2 3 4
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ ICFD BOUNDARY/INITIAL CONDITIONS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_BOUNDARY_PRESCRIBED_TURBULENCE
$# pid vtype imp lcid
1 2 2 3
*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_FREESLIP
$# pid
3
*ICFD_BOUNDARY_NONSLIP
$# pid
4
*ICFD_INITIAL
$# pid vx
0 &v_inlet
*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
*DEFINE_CURVE_TITLE
inlet turbulent viscosity
$# lcid sidr sfa sfo offa offo dattyp
3 &mu_turb
$# 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
8
$# pid1 pid2 pid3 pid4
1 2 3 4
*MESH_BL
$# pid nelth blth blfe blst
4 2 0.006 1
$ For LES and possibly RANS k-w
$$# pid nelth blth blfe blst
$ 4 5 0.006 1e-4 2
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ DATABASE (OUTPUT) $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*ICFD_DATABASE_DRAG
$# pid
4
*ICFD_DATABASE_TIMESTEP
$# outlv
1
*DATABASE_BINARY_D3PLOT
&dt_plot
*END