Commit Graph

10068 Commits

Author SHA1 Message Date
Denny Tjahjanto 1bf3b978eb modifying the criteria for the sum of microstructure fraction.
previously was:
if (the_sum /= 1.0_pReal) then (error 170)
this condition is too strict. it may give problem with some numerical truncation error.

now becomes:
if (abs(the_sum - 1.0_pReal) >= 1.0e-10_pReal) then (error 170)
2009-12-02 13:08:14 +00:00
Denny Tjahjanto 59d22d47b2 introduction of a possibility to have homogeneous element (all ips in one element are identical, sort of reduced integration)
and bugs-fixing in crystallite.f90, homogenization_RGC.f90, numerics.f90.
2009-11-24 15:00:25 +00:00
Denny Tjahjanto 6702cb3baa Introduction of a numerical viscosity into the RGC scheme to improve the convergent behavior and the numerical stability of the scheme (see: homogenization_RGC.f90). These changes have been incorporated in all related subroutines (homogenization.f90, IO.f90, numerics.config and numerics.f90). 2009-11-17 13:42:38 +00:00
Denny Tjahjanto cb88019aa6 introduced a flexibility in cut-backing scheme in homogenization.f90 and in crystallite.f90:
(1) subStepSizeHomog and subStepSizeCryst := size of substep when cut-back is applied (initially was hard-coded).
(2) stepIncreaseHomog and stepIncreaseCryst := step increase when calculation for substep converge (was also hardcoded).

introduced a possibility to choose different finite difference scheme, i.e., forward-, backward- and central-difference, for computing grain numerical tangent. note that central-difference scheme will slow down the computation significantly. please use it only if necessary.

parameters to set these new features have been included in numerics.f90 and numerics.config, whereas corresponding error messages have been introduced in the IO.f90
2009-11-10 13:36:27 +00:00
Luc Hantcherli 67f87486b1 in constitutive_dislotwin.f90:
in constitutive_nonlocal.f90:

Derivatives of shear rates w.r.t. resolved shear stress HAVE to be positive.
Computation of dgdot_dtauslip is now correct.
2009-11-06 17:46:12 +00:00
Philip Eisenlohr b03f229613 climb equation corrected
minor phrase polishing
2009-11-02 14:20:21 +00:00
Philip Eisenlohr f96f9332cf added some comments and made sure that texture distribution among a large number of IPs is statistically sound. 2009-11-02 08:03:14 +00:00
Denny Tjahjanto 8f40c516bb added to the previous one 2009-10-30 10:00:17 +00:00
Denny Tjahjanto 2068346f6d just small changes in the 'default' value of RGC numerical parameters. 2009-10-30 09:54:52 +00:00
Christoph Kords 1e5a0318f3 don't do any cutbacks in homogenization when my materialpoint consists of only one grain. 2009-10-27 08:31:45 +00:00
Christoph Kords c766ba2e3a minimum substepping size in homogenization and crystallite is now controlled by two independent parameters subStepMinHomog and subStepMinCryst respectively.
deleted flush statements where they are not needed, since they seriously slow down computation.
2009-10-26 16:43:43 +00:00
Denny Tjahjanto f50d3291f9 sorry, back to the previous version. grain deformation output is part of crystallite.f90, no longer done by homogenization. material.config reflects the changes. 2009-10-22 16:59:24 +00:00
Denny Tjahjanto 9eb1a6c3fb new, more beautiful version of the UserOutput.pdf 2009-10-22 15:46:25 +00:00
Denny Tjahjanto d344aaf3a0 added possibility to output individual grain deformation gradient in homogenization_RGC.f90 and the homogenization.f90 has been modified accordingly. see material.config for the key-words to output the individual grain deformation gradient in the homogenization block. 2009-10-22 09:24:05 +00:00
Philip Eisenlohr 1dcb80753c tidying up code and reversing order in debug timing output 2009-10-22 09:14:17 +00:00
Philip Eisenlohr 67f4bdfaa0 volume fraction where new twins may form is now limited to (1-F) instead of 1...
"relevantResistance" is set to 1 Pa as default
2009-10-22 08:58:14 +00:00
Philip Eisenlohr 5d01e30f77 deleted debugging statements that print out interaction/hardening matrixes 2009-10-21 13:41:49 +00:00
Philip Eisenlohr 5d5e7eb8f8 corrected uncritical mix-up of Ntwin and Nslip in reshaping fcc interaction (slip--twin) 2009-10-21 13:41:09 +00:00
Philip Eisenlohr 4e98935287 changed lattice_interaction matrices to (other:me) notation
fixed small mistake in hexagonal twin--slip interaction matrix

adopted above switched notation for hardening matrix calculation
shortened dotState by introducing dot_product notation
2009-10-21 13:10:12 +00:00
Christoph Kords 9892fd9a10 sorry: initialization of periodicBC was erroneous 2009-10-20 16:38:05 +00:00
Philip Eisenlohr e1586d5059 fixed (probably severe) bug in hexagonal twin system transformation into ortho-hexagonal coordinates.
cleaning up of twin system nomenclature

introduced lookup mechanism  to calculate the twinning shears depending on the c/a ratio of the present structure (was [wrongly!!] hardcoded to Titanium)
2009-10-20 16:13:25 +00:00
Christoph Kords c1ee34d235 constitutive_nonlocal:
- read in activation energy for dislocation glide from material.config
- changed naming of dDipMin/Max to dLower/dUpper
- added new outputs: rho_dot, rho_dot_dip, rho_dot_gen, rho_dot_sgl2dip, rho_dot_dip2sgl, rho_dot_ann_ath, rho_dot_ann_the, rho_dot_flux, d_upper_edge, d_upper_screw, d_upper_dot_edge, d_upper_dot_screw
- poisson's ratio is now calculated from elastic constants
- microstrucutre has state as first argument, since this is our output variable
- periodic boundary conditions are taken into account for fluxes and internal stresses. for the moment, flag has to be set in constitutive_nonlocal. 
- corrected calculation for dipole formation by glide
- added terms for dipole formation/annihilation by stress decrease/increase 

constitutive:
- passing of arguments is adapted for constitutive_nonlocal model

crystallite:
- in stiffness calculation: call to collect_dotState used wrong arguments
- crystallite_postResults uses own Tstar_v and temperature, no need for passing them from materialpoint_postResults

homogenization:
- crystallite_postResults uses own Tstar_v and temperature, no need for passing them from materialpoint_postResults

IO:
- changed error message 229

material.config:
- changed example for nonlocal constitution according to constitutive_nonlocal

all:
- added some flush statements
2009-10-20 14:36:03 +00:00
Philip Eisenlohr 48e642bb15 twin resistance evolution did not use magnitude of shear rate (dot gamma) but the signed quantity... leads to non-physical oscillations of twin resistance. 2009-10-20 12:15:37 +00:00
Philip Eisenlohr 7914f80931 stiffness calculation for structure > 3 was missing: "case(3)" --> now "case(3:)" as in all other constitutive_xyz..! 2009-10-19 14:47:52 +00:00
Philip Eisenlohr a94e551c5f absolute tolerance was just fine -- residuum is in Lp not in stress. Hence, unit is strain and not Pa... 2009-10-19 12:53:56 +00:00
Philip Eisenlohr ba27947142 material point now cuts back by 1/8
crystallite does not accelerate anymore, since, typically, longer step immediately fails and uses resources in vain. (future: remember number of successful steps to increase step size after x of those...)
2009-10-19 12:50:59 +00:00
Philip Eisenlohr b5fc0a9769 small rearrangement of cutback dealings. may give minute speed improvement... 2009-10-19 12:46:02 +00:00
Philip Eisenlohr 5a5d461a30 changed abs tolerance in stress loop to 1 Pa (from 1e-8 Pa ..?) 2009-10-19 12:44:20 +00:00
Christoph Kords 6e613303a3 2009-10-19 08:01:02 +00:00
Christoph Kords ba02dfca1e 2009-10-19 07:56:47 +00:00
Philip Eisenlohr 992077e88e fixed cut back issue with Marc. Necessity to introduce compMode 7 to capture tangent restoration at lovl=4 call. 2009-10-17 09:25:36 +00:00
Philip Eisenlohr 974116808b fixed a potential memory leak for hexagonal structures. added some status output to constitutive_xx 2009-10-15 20:02:52 +00:00
Philip Eisenlohr 5adcb5e36c now contains the number of grains "m" as first entry (thanks to Koen for appending the document) 2009-10-15 11:53:07 +00:00
Philip Eisenlohr 7f84961c93 less debug clutter... 2009-10-14 13:23:52 +00:00
Philip Eisenlohr c3cb72d356 put some comments to hybridIA 2009-10-14 13:21:03 +00:00
Luc Hantcherli 00450b2c16 Added constraint on the dipole distance
if dipole distance > dislocation mean free distance then
   dipole distance = dislocation mean free distance
2009-10-13 18:14:44 +00:00
Luc Hantcherli 3bf3d7ddbd New version of constitutive_dislotwin after first-round checks 2009-10-13 15:05:21 +00:00
Franz Roters 2c1a610b14 removed Koen's loading subroutine from abaqus interface 2009-10-13 06:55:15 +00:00
Philip Eisenlohr 0a34da292e # no need for materialpoint_results in hypela2
# homogenization updated to be compatible with abaqus interface
2009-10-12 17:01:42 +00:00
Luc Hantcherli ca1c61bf98 Changed constitutive_dislobased into constitutive_dislotwin 2009-10-12 16:44:17 +00:00
Philip Eisenlohr 8b66b8def2 # small remark to set "-free" switch for compile
# rename to Abaqus-compatible ".f" extension
2009-10-12 16:32:57 +00:00
Philip Eisenlohr 7d05845d5d # now $ID aware
# LF as line separation and some tidy up
2009-10-12 16:26:16 +00:00
Philip Eisenlohr 2c06cad4d0 now $ID aware 2009-10-12 16:25:48 +00:00
Philip Eisenlohr 21cad32137 # new interface for Abaqus
# IO has some additional functionality for Abaqus parsing
# ping pong scheme in FE interface now similar (and more human understandable) in both versions
# mesh has better splitting of different tasks, plus operation on database whenever possible
# FEsolver as new global var to indicate FEM solver type
# computation mode reshuffling: 6 is now Marc special case of recycling...
2009-10-12 16:01:49 +00:00
Philip Eisenlohr 02602144d2 can now be executed from different directories...but will operate on "its" one 2009-10-12 14:18:54 +00:00
Luc Hantcherli 3f41b271fb The new dislocation model is now implemented in constitutive_dislotwin.f90
(seems to run fine, but still under investigation)
2009-10-09 20:28:23 +00:00
Christoph Kords 4ff497e5ba mesh_build_sharedElems does not need an input argument anymore 2009-10-08 09:23:15 +00:00
Philip Eisenlohr e7247551f0 changed "build_sharedElements" to use (then existing) internal element data structure instead of reading again from the input file. The data structure is already established by "build_elements"... 2009-10-08 09:01:59 +00:00
Luc Hantcherli 8cb156dc35 in Documentation\ConstitutiveLaw\DisloTwinLaw
Added tex source that generates PDF-file describing dislocation glide as implemented in constitutive_dislotwin.f90
2009-10-08 07:33:01 +00:00
Luc Hantcherli bb8a71557b Added comment on FCC different interaction types
1 --> self
2 --> coplanar
3 --> collinear
4 --> Hirth locks
5 --> glissile junctions
6 --> Lomer locks
2009-10-07 17:00:35 +00:00