Linear Static Analysis (Elasticity, Parallel)

To run 4 parallel static analysis(elasticity), and you can use the data in tutorial/02_elastic_hinge_parallel.

Analysis target

Item	Description	Notes	Reference
Type of analysis	Linear static analysis	!SOLUTION,TYPE=STATIC
Number of nodes	84,056
Number of elements	49,871
Element type	10-node tetrahedron quadratic element	!ELEMNT,TYPE=342	Element Library
Material name	STEEL	!MATERIAL,NAME=STEEL	Material Data
Material property	ELASTIC	!ELASTIC
Boundary conditions	Restraint, Concentrated force
Matrix solution	CG/SSOR	!SOLVER,METHOD=CG,PRECOND=1

Analysis area of each node

Fig. 4.2.1 : Analysis area of each node

Analysis

Extract the code FrontISTR code and go to the directory in this example to check if you have the files necessary for analysis.

File name	Type	Role
`hecmw_ctrl.dat`	Global control data
`hinge.cnt`	Analysis control data
`hinge.msh`	Mesh data
`hecmw_part_ctrl.dat`	Domain segmentation control data	Control data to divide the mesh data into regions by `hecmw_part1`

$ tar xvf FrontISTR.tar.gz
$ cd FrontISTR/tutorial/02_elastic_hinge_parallel
$ ls
hecmw_ctrl.dat  hecmw_part_ctrl.dat  hinge.cnt  hinge.msh

A stress analysis is performed to constrain the displacement of the constrained surface and add concentrated loads to the forced surface.

The overall control data, analysis control data and domain division control data are shown below.

Global control data `hecmw_ctrl.dat`

#
# for partitioner
#
!MESH, NAME=part_in,TYPE=HECMW-ENTIRE # The original mesh data to be split in hecmw_part1
 hinge.msh
!MESH, NAME=part_out,TYPE=HECMW-DIST  # File name after splitting by hecmw_part1
 hinge_4
#
# for solver
#
!MESH, NAME=fstrMSH, TYPE=HECMW-DIST  # Specify the mesh data to be split
 hinge_4
!CONTROL, NAME=fstrCNT                # Specify analysis control data
 hinge.cnt
!RESULT, NAME=fstrRES, IO=OUT         # Specify the result data
 hinge.res
!RESULT, NAME=vis_out, IO=OUT         # Specify the visualization data
 hinge_vis

Analysis control data `hinge.cnt`

#  Control File for FISTR
## Analysis Control
!VERSION                   # Specify the version of the file format
 3
!SOLUTION, TYPE=STATIC     # Specify the type of analysis
!WRITE,RESULT              # Specification of the result data output
!WRITE,VISUAL              # Specify the output of visualization data
## Solver Control
### Boundary Conditon
!BOUNDARY
 BND0, 1, 3, 0.000000      # Restrained surface 1
!BOUNDARY
 BND1, 1, 3, 0.000000      # Restrained surface 2
!CLOAD
 CL0, 1, 0.01000           # Specify a forced surface
### Material
!MATERIAL, NAME=STEEL      # Specify material properties
!ELASTIC                   # Definition of elastic substances
 210000.0, 0.3
!DENSITY                   # Definition of mass density
 7.85e-6
### Solver Setting
!SOLVER,METHOD=CG,PRECOND=1,ITERLOG=YES,TIMELOG=YES  # Solver control
 10000, 2
 1.0e-08, 1.0, 0.0
## Post Control
!VISUAL,metod=PSR          # Specify the visualization methods
!surface_num=1             # Number of surfaces in a surface rendering
!surface 1                 # Specify the contents of the surface
!output_type=VTK           # Specify the type of the visualization file
!END                       # Indicates the end of the analysis control data

Domain division control data `hecmw_part_ctrl.dat`

!PARTITION,TYPE=NODE-BASED,METHOD=PMETIS,DOMAIN=4,UCD=part.inp

Analysis procedure

In order to run FrontISTR at MPI, the mesh data hinge.msh is first divied into four regions.

$ hecmw_part1
Oct 07 11:04:52 Info: Reading mesh file...
Oct 07 11:04:52 Info: Starting domain decomposition...
Oct 07 11:04:52 TH(0/8) Info: Creating local mesh for domain #0 ...
Oct 07 11:04:52 TH(2/8) Info: Creating local mesh for domain #1 ...
Oct 07 11:04:52 TH(6/8) Info: Creating local mesh for domain #2 ...
Oct 07 11:04:52 TH(7/8) Info: Creating local mesh for domain #3 ...
Oct 07 11:04:52 Info: Domain decomposition done

New files called hinge_4.x and part.inp will be generated.

$ ls
hecmw_ctrl.dat  hecmw_part_ctrl.dat  hinge.msh  hinge_4.1  hinge_4.3
hecmw_part.log  hinge.cnt            hinge_4.0  hinge_4.2  part.inp

Next, you will execute the FrontISTR command fistr1 with MPI.

$ mpirun -np 4 fistr1 -t 1
(MPI 4 parallel, 1 OpenMP thread)

##################################################################
#                         FrontISTR                              #
##################################################################
---
version:    5.1.0
git_hash:   acab000c8c633b7b9d596424769e14363f720841
build:
  date:     2020-10-05T07:39:55Z
  MPI:      enabled
  OpenMP:   enabled
  option:   "-p --with-tools --with-refiner --with-metis --with-mumps --with-lapack --with-ml --with-mkl "
  HECMW_METIS_VER: 5
execute:
  date:       2020-10-07T11:07:21+0900
  processes:  4
  threads:    1
  cores:      4
  host:
    0: flow-p06
    1: flow-p06
    2: flow-p06
    3: flow-p06
---
...
 Step control not defined! Using default step=1
 fstr_setup: OK
 Start visualize PSF 1 at timestep 0

 loading step=    1
 sub_step= 1,   current_time=  0.0000E+00, time_inc=  0.1000E+01
 loading_factor=    0.0000000   1.0000000
### 3x3 BLOCK CG, SSOR, 2
      1    2.183567E+00
      2    2.423900E+00
      3    2.939117E+00
...
   2084    1.158654E-08
   2085    1.032414E-08
   2086    9.436273E-09
### Relative residual = 9.43589E-09

### summary of linear solver
      2086 iterations      9.435886E-09
    set-up time      :     4.695220E-02
    solver time      :     7.103976E+01
    solver/comm time :     1.929294E+01
    solver/matvec    :     1.544405E+01
    solver/precond   :     3.243278E+01
    solver/1 iter    :     3.405549E-02
    work ratio (%)   :     7.284205E+01

 Start visualize PSF 1 at timestep 1
### FSTR_SOLVE_NLGEOM FINISHED!

 ====================================
    TOTAL TIME (sec) :     72.42
           pre (sec) :      0.29
         solve (sec) :     72.13
 ====================================
 FrontISTR Completed !!

The analysis is completed when FrontISTR Completed!! is displayed, the analysis is done.

Analysis Results

Once the analysis is complete, several new files will be created.

$ ls
0.log       FSTR.dbg.3           hinge.cnt      hinge.res.2.1  hinge_vis_psf.0000
1.log       FSTR.msg             hinge.msh      hinge.res.3.0  hinge_vis_psf.0000.pvtu
2.log       FSTR.sta             hinge.res.0.0  hinge.res.3.1  hinge_vis_psf.0001
3.log       hecmw_ctrl.dat       hinge.res.0.1  hinge_4.0      hinge_vis_psf.0001.pvtu
FSTR.dbg.0  hecmw_part.log       hinge.res.1.0  hinge_4.1      part.inp
FSTR.dbg.1  hecmw_part_ctrl.dat  hinge.res.1.1  hinge_4.2
FSTR.dbg.2  hecmw_vis.ini        hinge.res.2.0  hinge_4.3

The *.res.* is the result data, which contains results of analysis of each MPI node of FrontISTR.

The *_vis_* is called visualization data, and can be displayed by general-purpose visualization software. In this example, the data is output in VTK format and can be displayed using ParaView or other visualization software.

Analysis of Mises Stress (Displayed in VTK)

Fig. 4.2.2 Analytical results for Mises stress(displayed in VTK)

Linear Static Analysis (Elasticity, Parallel)