# Basics : Thermal flow — Welcome to LS-DYNA Examples

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This LS-DYNA simulation shows a simple ICFD forced convection input deck with a coarse mesh. Compared to the basic cylinder flow problem, this problem adds the keywords to solve the heat equation. A 20 degree cooling wave flows over a hot cylinder that maintains a constant temperature of 80 degrees. The domain is initialized at 10 degrees.

## Description

This LS-DYNA simulation shows a simple ICFD forced convection input deck with a coarse mesh. Compared to the basic cylinder flow problem, this problem adds the keywords to solve the heat equation. A 20 degree cooling wave flows over a hot cylinder that maintains a constant temperature of 80 degrees. The domain is initialized at 10 degrees.

## Animated Result

Fluid velocity fringes

## Keywords

```*KEYWORD
*TITLE
*DATABASE_BINARY_D3PLOT
*DEFINE_CURVE_TITLE
*ICFD_BOUNDARY_FREESLIP
*ICFD_BOUNDARY_PRESCRIBED_PRE
*ICFD_BOUNDARY_PRESCRIBED_TEMP
*ICFD_BOUNDARY_PRESCRIBED_VEL
*ICFD_BOUNDARY_NONSLIP
*ICFD_CONTROL_TIME
*ICFD_DATABASE_DRAG
*ICFD_INITIAL
*ICFD_MAT
*ICFD_PART
*ICFD_PART_VOL
*ICFD_SECTION
*INCLUDE
*MESH_BL
*MESH_SURFACE_ELEMENT
*MESH_SURFACE_NODE
*MESH_VOLUME
*PARAMETER
*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 R8.0.0 (or higher) with double precision
\$X
\$X------------------------------------------------------------------------------
\$# UNITS: Dimensionless.
\$X------------------------------------------------------------------------------
\$X
*KEYWORD
*TITLE
ICFD Cylinder 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     100.0
R  dt_plot      1.00
\$
\$--- Fluid
\$
R  v_inlet       1.0
Rrho_fluid       1.0
R mu_fluid     0.005
R dt_fluid     0.000
RTemp_init    10.000
RTemp_inle    20.000
R Temp_cyl    80.000
R HC_fluid     1000.
R TC_fluid      200.
\$
\$---+----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
\$---+----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
\$#      hc        tc
&HC_fluid &tc_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_VEL
1         1         1         1
*ICFD_BOUNDARY_PRESCRIBED_VEL
1         2         1         2
*ICFD_BOUNDARY_PRESCRIBED_TEMP
\$#     pid      lcid
1         3
*ICFD_BOUNDARY_PRESCRIBED_PRE
\$#     pid      lcid
2         2
*ICFD_BOUNDARY_FREESLIP
\$#     pid
3
*ICFD_BOUNDARY_NONSLIP
\$#     pid
4
*ICFD_BOUNDARY_PRESCRIBED_TEMP
\$#     pid      lcid
4         4
*ICFD_INITIAL
\$#     pid        vx        vy        vz      temp
0                                     10.
*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
Temp inlet
\$#    lcid      sidr       sfa       sfo      offa      offo    dattyp
3                    &Temp_inle
\$#                a1                  o1
0.0                 1.0
10000.0                 1.0
*DEFINE_CURVE_TITLE
Temp cylinder
\$#    lcid      sidr       sfa       sfo      offa      offo    dattyp
4                    &Temp_cyl
\$#                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
1
\$#    pid1      pid2      pid3      pid4
1         2         3         4
*MESH_BL
\$#     pid     nelth
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
*DATABASE_BINARY_D3PLOT
&dt_plot
*END```