TEAM 24 Problem — Welcome to LS-DYNA Examples

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The TEAM 24 workshop problem consists of a rotor mounted on a nonmagnetic stainless steel shaft and a fixed stator. The rotor is locked at a specific angle with respect to the stator. The steel magnetization curve and conductivity have been measured and are provided as input. The coils are modelled as stranded conductors with a provided voltage, resistance and number of turns. Coil current, torque, search coil flux, and Hall probe flux density are Post Treatment quantities. This input decks shows the EM monolithic solver’s advanced capabilities that allow to solve non-linear time transient actuator or electric motor problems while removing the need to mesh the air

Description

LS-DYNA’s EM solver provides a novel FEM/BEM monolithic approach which allows the user to solve non-linear time transient actuator or electric motor problems while removing the need to mesh the air and fully couple the results to LS DYNA’s mechanical solver. This benchmark problem has been proposed by N. Allen and D.Rodger in “Description of TEAM Workshop Problem 24: Nonlinear Time-Transient Rotational Test Rig”. School of Electrical Engineering, University of Bath, Bath, BA2 7AY, U.K. It consists of a rotor mounted on a nonmagnetic stainless steel shaft and a fixed stator. The rotor is locked at a specific angle with respect to the stator. The steel magnetization curve and conductivity have been measured and are provided as input. The coils are modelled as stranded conductors with a provided voltage, resistance and number of turns. Coil current, torque, search coil flux, and Hall probe flux density are Post Treatment quantities.

To solve this problem, either the current is considered a known quantity and directly imposed (see current_team24.k). In that case, the coil is not part of the FEM/BEM system (The current generates a external source term on the FEM/BEM system) and therefore mtype=1 in the coil’s associated EM_MAT. The alternative is to use a voltage driven coil. In that case, the current is considered as an unknown and therefore mtype=2 in the coil’s associated EM_MAT. In addition to the voltage, the resistance and the number of turns must also be provided in EM_CIRCUIT_SOURCE.

Keywords

*EM_DATABASE_PARTDATA
*EM_CIRCUIT_SOURCE
*EM_CONTROL
*EM_CONTROL_TIMESTEP
*EM_CONTROL_COUPLING
*EM_SOLVER_BEM
*EM_SOLVER_BEMMAT
*EM_CIRCUIT_ROGO
*EM_MAT_001
*EM_MAT_002
*EM_EOS_PERMEABILITY
*EM_POINT_SET
*EM_DATABASE_POINTOUT
*EM_SOLVER_FEMBEM_MONOLITHIC
*EM_OUTPUT

Reduced Input

*KEYWORD
*TITLE
TEAM 24
\$ Example provided by TailSiT GmbH
\$X——————————————————————————
\$X
\$X 1. Run file as is.
\$X Recommended LS-DYNA MPP Dev January 2022 (or more recent)
\$X Double precision
\$X
\$X——————————————————————————
\$# UNITS: (kg/m/s)
\$X——————————————————————————
\$X
*PARAMETER
R T_end 0.3
R dt_plot 2.e-3
\$
\$— em
R em_cond 1.2
R em_dt 5.e-4
R sigma 4.54e6
R res 1.545
R turns 350
\$
\$
R dt_struc 5.e-4
Rrho_struc 7000.e-6
R E_struc 2.e11
R nu_struc 0.3
*INCLUDE
mesh_team24.k
\$ ****************************************************************************
\$ mechanics
\$ ****************************************************************************
\$——–1———2———3———4———5———6———7———8
*CONTROL_TERMINATION
\$ ENDTIM ENDCYC DTMIN ENDENG ENDMAS
&T_end
*CONTROL_TIMESTEP
15
*DEFINE_CURVE
15
0.,&dt_struc
1.,&dt_struc
*DATABASE_BINARY_D3PLOT
&dt_plot
*PART
cond
\$ pid secid mid eosid hgid grav adpopt tmid
1 1 1
*PART
cond
\$ pid secid mid eosid hgid grav adpopt tmid
2 1 2
*PART
cond
\$ pid secid mid eosid hgid grav adpopt tmid
3 1 3
*PART
cond
\$ pid secid mid eosid hgid grav adpopt tmid
4 1 4
*PART
cond
\$ pid secid mid eosid hgid grav adpopt tmid
5 1 5
*PART

6,1,6
*MAT_RIGID
6,7000e-6,200e9,0.3
1,7,7

*SECTION_SOLID
\$ sid elform
1 1
*MAT_RIGID
1,7000.,200e9,0.3
\$# cmo con1 con2
1.000000 7 7
\$# lco or a1 a2 a3 v1 v2 v3
0.000 0.000 0.000 0.000 0.000 0.000
*MAT_RIGID
2,7000.,200e9,0.3
\$# cmo con1 con2
1.000000 7 7
\$# lco or a1 a2 a3 v1 v2 v3
0.000 0.000 0.000 0.000 0.000 0.000
*MAT_RIGID
3,7000.,200e9,0.3
\$# cmo con1 con2
1.000000 7 7
\$# lco or a1 a2 a3 v1 v2 v3
0.000 0.000 0.000 0.000 0.000 0.000
*MAT_RIGID
4,7000e,200e9,0.3
\$# cmo con1 con2
1.000000 7 7
\$# lco or a1 a2 a3 v1 v2 v3
0.000 0.000 0.000 0.000 0.000 0.000
*MAT_RIGID
5,7000e,200e9,0.3
\$# cmo con1 con2
1.000000 7 7
\$# lco or a1 a2 a3 v1 v2 v3
0.000 0.000 0.000 0.000 0.000 0.000
\$ ****************************************************************************
\$ electromagnetism
\$ ****************************************************************************
*EM_DATABASE_PARTDATA
1
*EM_CONTROL
\$——–1———2———3———4———5———6———7———8
\$ emsol numls emdtinit emdtmax emtinit emtend ncyclFem ncyclBem
1 1000 5000
*EM_CONTROL_TIMESTEP
\$——–1———2———3———4———5———6———7———8
\$ TSTYPE DTCONST LCID FACTOR
1 &em_dt
*EM_CONTROL_COUPLING
,2
*EM_SOLVER_BEM
\$——–1———2———3———4———5———6———7———8
\$ relTol maxIter solveType precond uselast
1.e-8 10000 2 4 1
*EM_SOLVER_BEMMAT
\$——–1———2———3———4———5———6———7———8
\$ matId relTol
1 1.e-12
*EM_SOLVER_BEMMAT
\$——–1———2———3———4———5———6———7———8
\$ matId relTol
2 1.e-12
*EM_SOLVER_BEMMAT
\$——–1———2———3———4———5———6———7———8
\$ matId relTol
3 1.e-12
*EM_CIRCUIT_ROGO
\$——–1———2———3———4———5———6———7———8
\$ rogoId setID setType currType
1 3 1 1
*EM_CIRCUIT_ROGO
2 4 1 1
*EM_CIRCUIT_ROGO
3 3 1 3
*EM_CIRCUIT_ROGO
4 4 1 3
*EM_MAT_002
\$——–1———2———3———4———5———6———7———8
\$ em_mid mtype sigma eosId urel eosMure
1 4 &sigma 1000 10
*EM_MAT_002
\$——–1———2———3———4———5———6———7———8
\$ em_mid mtype sigma eosId murel eosMure
4 4 &sigma 1000 10
*EM_MAT_001
\$——–1———2———3———4———5———6———7———8
\$ em_mid mtype sigma eosId
5 1
*EM_MAT_002
6,2,0.,,1.
*EM_EOS_PERMEABILITY
10,1,301
\$ ****************************************************************************
\$B vs H curve
*DEFINE_CURVE
\$ LCID SIDR SFA SFO OFFA OFFO DATTYP
\$——–1———2———3———4———5———6———7
300 1.e4
0.000,0.000
0.100,1.000
00.400,1.413
00.801,1.594
01.601,1.751
02.402,1.839
03.203,1.896
04.003,1.936
04.804,1.967
06.405,2.008
08.007,2.042
09.608,2.073
11.210,2.101
12.811,2.127
14.412,2.151
17.615,2.197
20.818,2.240
24.020,2.281
27.223,2.321
30.426,2.361
33.629,2.400
39.634,2.472
60.,2.5
*EM_POINT_SET
1
1,0.0074,0.050687,0.0177
*EM_DATABASE_POINTOUT
1
1
*EM_SOLVER_FEMBEM_MONOLITHIC
\$——–1———2———3———4———5———6———7———8
\$ COUPLING KSP_TYPE KSP_ATOL KSP_RTOL KSP_MAXIT GMRES_RST DEBUG
0 1.e-8 1.e-4 10000
\$——–1———2———3———4———5———6———7———8
\$ NEWT_STOL NEWT_ATOL NEWT_RTOL NEWT_MAXI
0 1.e-3 1.e-8 1.e-3 50
\$——–1———2———3———4———5———6———7———8
\$ LS_ON LS_FTOL LS_GTOL LS_RTOL LS_SAMPL LS_NUM_SP LS_MAXFUN
2 0.01 0.5 0.01
*EM_OUTPUT
\$——–1———2———3———4———5———6———7———8
\$ matS matF solS solF mesh memory timing d3plotAsc
2 2 2 2 0 0 0 0
\$ mf2 gmv d3plotFor timeHist
0 0 0
\$——–1———2———3———4———5———6———7———8
\$ ****************************************************************************
*INCLUDE
\$current_team24.k
volt_team24.k
bhteam24.k
*END