Thermal-mechanical Metal-forming Thermal-mechanical Metal-forming Simulations in LSDYNA (revisited)Simulations in LSDYNA (revisited)

Rudolf BötticherRudolf BötticherTMB GmbHTMB GmbH

www.rudolf-boetticher.de www.rudolf-boetticher.de 

Ulm, 13.10.2006 www.rudolf-boetticher.de

MotivationMotivation Assess adaptive (space, time) Assess adaptive (space, time)

coupled simulations (SOLN=2) coupled simulations (SOLN=2) with plastic heating for nodal with plastic heating for nodal pressure tetraheadrons pressure tetraheadrons (ELFORM=13) and EFG elements.(ELFORM=13) and EFG elements.

1. Methods and Keywords

2. Adaptive 3D (EFG) Tets

3. Adaptive axi-2D

4. Conclusions

Ulm, 13.10.2006 www.rudolf-boetticher.de

Caution: SMP vs. SerialCaution: SMP vs. Serial!!

Using Real DMF solver and MMD ordering

stiffness matrix data -------------------------------------------------------------- number of equations = 4957 stiffness coefficients = 0.1 Mw

expanding memory to 1671039 imfisgy sym. storage 1 expanding memory to 1675184 imfisgy sym. storage 3 Memory Requirements: incore out-of-core TOTAL for linear algebra = 1.7 0.5 Mw TOTAL for entire job = 3.3 2.1 Mw TOTAL available = 20.0 20.0 Mw expanding memory to 19802133 imfisgy numeric storage ic

an INCORE solution will be performed

Symbolic Factorization CPU = 0.000E+00 seconds Numeric Factorization CPU = 1.000E+00 seconds

Using Real DMF solver and MMD ordering

stiffness matrix data -------------------------------------------------------------- number of equations = 3640 stiffness coefficients = 0.0 Mw

expanding memory to 1572951 imfisgy sym. storage 1 expanding memory to 1591753 imfisgy sym. storage 2 expanding memory to 1602395 imfisgy sym. storage 3 Memory Requirements: incore out-of-core TOTAL for linear algebra = 0.9 0.3 Mw TOTAL for entire job = 2.4 1.8 Mw TOTAL available = 20.0 20.0 Mw expanding memory to 19897094 imfisgy numeric storage ic

an INCORE solution will be performed

Symbolic Factorization CPU = 0.000E+00 seconds

******************************************************** * - WARNING - * * 544 negative eigenvalues detected during * * factorization of linear equation system. * ********************************************************

Implicit needs no mass scaling.

Thermal always implicit!

Ulm, 13.10.2006 www.rudolf-boetticher.de

KeywordsKeywords

*CONTROL_ADAPTIVE*CONTROL_ADAPTIVE *CONTROL_REMESHING*CONTROL_REMESHING *SECTION_SOLID_EFG*SECTION_SOLID_EFG

1,411,41

1.4,1.4,1.4,,,4,31.4,1.4,1.4,,,4,3 *CONTROL_IMPLICIT_GENERAL/AUTO*CONTROL_IMPLICIT_GENERAL/AUTO *CONTROL_THERMAL_SOLVER/TIMESTEP*CONTROL_THERMAL_SOLVER/TIMESTEP

Ulm, 13.10.2006 www.rudolf-boetticher.de

Single frames printed as *.jpg and mounted with Gifmerge. Scripting critical.

EFG has a mesh. Not adaptive alone. Adaption may fail at complicated surfaces.

LSPP Windows: saving of juxtaposed animation impossible.

3D Remarks: Results of explicit, implicit, adaptive and explicit EFG are sound.

Ulm, 13.10.2006 www.rudolf-boetticher.de

Better concept for displaying plastic strain at a given point for adaptive needed for LSPP

Plastic strain is projected correctly during adaption. Element and node numbers are reused!

Adaptive EFG works in explicit. Severe constraints on time step for mass scaling.

2D-axi Remarks:

EFG

Ulm, 13.10.2006 www.rudolf-boetticher.de

971.7600 projects plastic heating during adaption faulty.

2D-axi Remarks:

Ulm, 13.10.2006 www.rudolf-boetticher.de

Concluding RemarksConcluding Remarks

Lacking a more intuitive definition of SPC Lacking a more intuitive definition of SPC boundary conditions and forcing functions boundary conditions and forcing functions that are robust unter switching between that are robust unter switching between implicit, explicit and adaptive.implicit, explicit and adaptive.

Advantages of EFG often limited.Advantages of EFG often limited. Projections of plastic heating for axi-2D Projections of plastic heating for axi-2D

false.false. LSPP on Windows has still room for LSPP on Windows has still room for

improvements. improvements.