Electromagnetic forming problem
This LS-DYNA simulation shows a simple Electromagnetic forming example using the EM solver. A R,L,C circuit is defined in the coil which produces induced currents in the workpiece. This in turn generates Lorentz forces which cause the plate to move. Local heating is also produced and handled by the thermal solver.
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Electromagnetic forming problem
This LS-DYNA simulation shows a simple Electromagnetic forming example using the EM solver. A R,L,C circuit is defined in the coil which produces induced currents in the workpiece. This in turn generates Lorentz forces which cause the plate to move. Local heating is also produced and handled by the thermal solver.
This LS-DYNA simulation shows a simple Electromagnetic forming example using the EM solver. A R,L,C circuit is defined in the coil which produces induced currents in the workpiece. This in turn generates Lorentz forces which cause the plate to move. Local heating is also produced and handled by the thermal solver. An EM EOS couples back the temperature to the Electromagnetic solver by making the electromagnetic conductivity temperature dependent. The FEM and BEM matrices are recalculated every 20 timesteps in order to save calculation times. Coupling between EM and the thermal and mechanical solvers is automatic (no extra keyword mandatory).
EM current density fringes
*CONTROL_CONTACT *CONTROL_SOLUTION *CONTACT_SURFACE_TO_SURFACE *CONTROL_TERMINATION *CONTROL_TIMESTEP *CONTROL_THERMAL_SOLVER *CONTROL_THERMAL_TIMESTEP *DATABASE_BINARY_D3PLOT *DEFINE_CURVE_TITLE *EM_BOUNDARY *EM_CIRCUIT *EM_CIRCUIT_ROGO *EM_CONTROL *EM_CONTROL_TIMESTEP *EM_DATABASE_CIRCUIT0D *EM_EOS_MEADON *EM_EOS_TABULATED1 *EM_MAT_001 *EM_OUTPUT *EM_SOLVER_FEM *EM_SOLVER_BEM *EM_SOLVER_BEMMAT *END *HOURGLASS *INITIAL_TEMPERATURE_SET *KEYWORD *MAT_024 *MAT_RIGID *MAT_THERMAL_ISOTROPIC *PARAMETER *PART *SECTION_SHELL *SECTION_SOLID *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: (g/mm/s)
$X------------------------------------------------------------------------------
$X
*KEYWORD
*TITLE
EM Electromagnetic forming problem
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ EM CONTROL $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*EM_CONTROL
$ emsol
1
*EM_CONTROL_TIMESTEP
$# tstype dtcons lcid
1 &em_dt
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ EM CIRCUIT $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*EM_CIRCUIT
$ circid circtype lcid R L C V0
1 3 &em_res &em_ind &em_cap &em_v0
$ ssidCurr ssidVltin ssidVltOt partID
4 1 2
*EM_CIRCUIT_ROGO
$# rogid setid settype curtyp
4 4 1 1
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ EM BOUNDARY $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ remove rear and sides of the plate from the boundary mesh
$ this is optional and is used to speed up the run
*EM_BOUNDARY
$ ssid btype
6 9
*EM_BOUNDARY
$ ssid btype
8 9
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ EM MAT and EOS $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*EM_MAT_001
$ em_mid mtype sigma eos
1 2 &em_cond
*EM_MAT_001
$ em_mid mtype sigma eos
2 1
*EM_MAT_001
$ em_mid mtype sigma eos
3 4 &em_cond 1
*EM_EOS_TABULATED1
$# eosid lcid
1 43
*EM_EOS_MEADON
$# eosid c1 c2 c3 temuni v0 gamma expon
2 -5.35e-5 0.233 1.210 1 0 0 -0
$# lgtunit timunit adjust
1e-3 1 1
*EM_EOS_MEADON
$# eosid c1 c2 c3 temuni v0 gamma expon
3 -4.12e-5 0.133 1.145 1 0 0 -0
$# lgtunit timunit adjust
1e-3 1 1
*DEFINE_CURVE_TITLE
Conductivity function of temperature
$# lcid sidr sfa sfo offa offo dattyp
43
$# a1 o1
0.0 25.
25.0 25.
200.0 2.5
500.0 2.5
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ EM SOLVER $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*EM_SOLVER_BEMMAT
$# matid reltol
1 1e-6
*EM_SOLVER_BEMMAT
$# matid reltol
2 1e-6
*EM_SOLVER_BEM
$# reltol maxit stype precon uselas ncyclbem
1e-6 1000 2 2 1&em_bemmtx
*EM_SOLVER_FEM
$# reltol maxit stype precon uselas ncyclbem
1e-3 1000 1 1 1&em_femmtx
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
$ $
$ EM OUTPUT $
$ $
$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
*EM_OUTPUT
$ matS matF solS solF mesh
2 2 2 2 0
*EM_DATABASE_CIRCUIT0D
$# outlv
1
*END
Using conductive shells (less accurate in cases with high EM diffusion) :