Basics : Rugosity flow
This LS-DYNA simulation shows an atmospheric air flow going over a rough surface. The Standard k-epsilon model is activated through the use of ICFD_CONTROL_TURBULENCE. Furthermore, the rugosity parameters have been defined. The user is invited to change those parameters and check the influence on the surface shear vector. The mesh size has been chosen so that a Y+ of approximately 30 is maintained over the domain.
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Basics : Rugosity flow
This LS-DYNA simulation shows an atmospheric air flow going over a rough surface. The Standard k-epsilon model is activated through the use of ICFD_CONTROL_TURBULENCE. Furthermore, the rugosity parameters have been defined. The user is invited to change those parameters and check the influence on the surface shear vector. The mesh size has been chosen so that a Y+ of approximately 30 is maintained over the domain.
This LS-DYNA simulation shows an atmospheric air flow going over a rough surface. The Standard k-epsilon model is activated through the use of ICFD_CONTROL_TURBULENCE. Furthermore, the rugosity parameters have been defined. The user is invited to change those parameters and check the influence on the surface shear vector. The mesh size has been chosen so that a Y+ of approximately 30 is maintained over the domain.
Turbulent intensity fringes
*DATABASE_BINARY_D3PLOT *DEFINE_CURVE_TITLE *END *ICFD_BOUNDARY_FREESLIP *ICFD_BOUNDARY_PRESCRIBED_PRE *ICFD_BOUNDARY_PRESCRIBED_VEL *ICFD_BOUNDARY_NONSLIP *ICFD_CONTROL_OUTPUT *ICFD_CONTROL_TIME *ICFD_CONTROL_TURBULENCE *ICFD_INITIAL *ICFD_MAT *ICFD_PART *ICFD_PART_VOL *ICFD_SECTION *INCLUDE *KEYWORD *MESH_VOLUME_ELEMENT *MESH_VOLUME_NODE *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 R9.0.0 (or higher) with double precision $X $X------------------------------------------------------------------------------ $# UNITS: (kg/m/s) $X------------------------------------------------------------------------------ $X *KEYWORD *TITLE ICFD Rugosity study *INCLUDE mesh.k $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8 $ $ $ PARAMETERS $ $ $ $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8 *PARAMETER R T_end 5.0 R dt_plot 0.05 $ $--- Fluid $ R v_inlet 16.0 Rrho_fluid 1.22500 R mu_fluid 1.7895e-5 R dt_fluid 0.000 R ks_rug 0.5e-3 R cs_rug 0.5 $ $---+----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 $# tmod submcd wlaw ks cs 1 1 1 &ks_rug &cs_rug $# ce1 ce2 sigmae sigmak cmu ccut 1.44 1.92 1.3 1.0 0.09 -1 *ICFD_CONTROL_OUTPUT $# mslv 3 $---+----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 $# pid secid mid 10 1 1 $---+----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_FREESLIP $# pid 3 *ICFD_BOUNDARY_NONSLIP $# pid 4 *ICFD_INITIAL $# pid vx 0 16 *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 $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8 $ $ $ DATABASE (OUTPUT) $ $ $ $---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8 *DATABASE_BINARY_D3PLOT &dt_plot *END