Commit Graph

17 Commits

Author SHA1 Message Date
Christoph Kords fce7590c17 * now able to choose method for state integration (integrator and integratorStiffness in numerics.config); standard is "Fixed Point Iteration", which is basically the same as before; others available are "Explicit Euler", "AdaptiveEuler", "Classical Runge-Kutta" and "Runge-Kutta Cash-Karp"
* now remembering stiffness similar to how we do it for Lp etc.; avoids undefined stiffness values for nonconverged stiffness calculation

* non-local stuff:
   * changed non-local kinetics (Gilman2002)
   * enforce zero shearrate for overall carrrier density below relevant density
   * enforce zero density for those states that become negative and were below relevant density before
   * dislocation velocity is not limited by V^(1/3) / dt anymore
2010-10-01 12:18:49 +00:00
Alankar Alankar 8488cafe3a now consistent with numerics.f90 values 2010-09-21 14:37:52 +00:00
Christoph Kords dba4ae7ef1 new numerics parameter "defgradTolerance" replaces "relevantStrain" in cpfem, since "relevantStrain" is also used in crystallite but in a different context.
"defgradTolerance" gets the same standard value as "relevantStrain" so calculations should be consistent with older ones
2010-05-20 14:55:11 +00:00
Denny Tjahjanto 414050303b forgotten: the change in the input config 2010-03-24 13:28:46 +00:00
Denny Tjahjanto 3ab5cdc770 Additional feature to the RGC scheme: The volumetric consistency constraint. This is implemented by penalizing any volumetric discrepancy which occurs due to severe relaxation. The penalty for volume inconsistency is described using a power-law model. The setting for this function can be done in the numerics.config via three new parameters, i.e., maxvoldiscrepancy_RGC, voldiscrepancymod_RGC and discrepancypower_RGC. For monintoring, an extra output variable in prescribed in the material.config in the RGC section, namely "(output) volumediscrepancy".
IO.f90 and numerics.f90 has been modified accordingly to accommodate these changes
2009-12-16 16:20:53 +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
Denny Tjahjanto 8f40c516bb added to the previous one 2009-10-30 10:00:17 +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
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 5a5d461a30 changed abs tolerance in stress loop to 1 Pa (from 1e-8 Pa ..?) 2009-10-19 12:44:20 +00:00
Franz Roters 2029b23f98 added version information to all files
do NOT edit text like this:
$Id: constitutive_phenopowerlaw.f90 406 2009-08-31 14:13:10Z MPIE\f.roters $
2009-08-31 15:09:15 +00:00
Denny Tjahjanto 3ea17dd2fd CPFEM.f90 >>> A very small, not important thing.
homogenization.f90 and crystallite.f90 >>> Correction in the algorithm to count the iteration distribution (for better statistics).

material.config and numerics.config >>> more collection of parameters.
2009-08-28 15:05:14 +00:00
Denny Tjahjanto 644265381e mpie_cpfem_marc.f90 >>> changing the compilation sequence of modules: numerics.f90 and IO.f90 move up, while math.f90 down.
IO.f90 >>> adding "inRad" instead of using inRad from math.f90 module, since math.f90 module is now below IO.f90.

numerics.f90 >>> now can read the parameter "fixed_seed" from numerics.config. this parameter is used to set a pseudo-random number generator/fixed seeding. default value is 0 (zero), which will give fully random number.

math.f90 >> adding a possibility to fix the seeding (i.e., pseudo random number)

numerics.config >>> add a new parameter: "fixed_seed"
2009-08-27 15:30:40 +00:00
Christoph Kords 8ed3ddc03b now with first draft of nonlocal constitutive law
debugging memory leak closed
debugging counters corrected

center of gravity stored in mesh

state updated is now split into a collecting loop and an execution

updateState and updateTemperature fill sequentially separate logicals and evaluate afterwards to converged

added 3x3 transposition function, norm for 3x1 matrix and 33x3 matrix multiplication in math

non-converged crystallite triggers materialpoint cutback (used to respond elastically)

non-converged materialpoint raises terminal illness which in turn renders whole FE increment useless by means of odd stress/stiffness and thus waits for FE cutback
2009-08-11 16:31:57 +00:00
Christoph Kords fe2f3e4d36 - added sanity check for temperature tolerance
- added temperature tolerance in numerics.config
2009-07-02 16:37:48 +00:00
Franz Roters a6ccfe2e44 restructured the repository: renamed trunk into code, moved documentation one directory up, therefore you can now checkout either code or documentation only if you like 2009-06-25 07:17:59 +00:00