[CIG-SEISMO] SPECFEM3D - test case for meshfem3D "simple model"
Camille Mazoyer
mazoyer at univ-brest.fr
Tue Mar 8 15:26:29 PST 2011
Hello,
I'm an engineer in scientific computing at Institut Universitaire
Européen de la Mer (IUEM), Brest, France. One of the team with whom I
work with would like to use SPECFEM3D in order to study submarine
seisms and their Hydroacoustic propagation.
Therefore, I'm learning how to use your software for helping this
team. I started with the example of mesh generation called "simple
model" found in
examples/meshfem3D_examples/simple_model.Unfortunately, I didn't
manage to make this example work. I probably forgot to do something
but I can't see where: I just copied the files in
in_data_files/meshfem3D_files as it is explained in the README of the
example. And I didn't modify any of the files.
After executing xmeshfem3D, I've got elements with skewness of 81%,
which is not correct. I send you in an attached file the
output_mesher.txt. I hope this file will help you find what I missed
in my simulation.
Thanks a lot for your help.
I am looking forward to work with this software which seems very accomplished.
Camille Mazoyer
-------------- next part --------------
******************************************
*** Specfem3D MPI Mesher - f90 version ***
******************************************
Reading interface data from file
../in_data_files/meshfem3D_files/interfaces.dat to count the spectral elements
creating global slice addressing
Spatial distribution of slice numbers:
2 3
0 1
This is process 0
There are 4 MPI processes
Processes are numbered from 0 to 3
There are 64 elements along xi
There are 64 elements along eta
There are 15 elements along Z
There are 11 spectral elements along Z in layer 1
There are 4 spectral elements along Z in layer 2
There are 2 slices along xi
There are 2 slices along eta
There is a total of 4 slices
Shape functions defined by NGNOD = 8 control nodes
Surface shape functions defined by NGNOD2D = 4 control nodes
region selected:
latitude min = 33.1000000000000
latitude max = 34.1000000000000
longitude min = -118.900000000000
longitude max = -117.900000000000
this is mapped to UTM in region 11
UTM X min = 322693.294119200
UTM X max = 416981.317468119
UTM Y min = 3663774.68063354
UTM Y max = 3773402.80542979
UTM size of model along X is 94.2880233489190 km
UTM size of model along Y is 109.628124796243 km
Bottom of the mesh is at a depth of 30.0000000000000 km
using UTM projection in region 11
Reading interface data from file
../in_data_files/meshfem3D_files/interfaces.dat
**************************
creating mesh in the model
**************************
**************************
Checking mesh quality
**************************
start computing the minimum and maximum edge size
done processing
------------
mesh quality parameter definitions
equiangle skewness: 0. perfect 1. bad
skewness max deviation angle: 0. perfect 90. bad
edge aspect ratio: 1. perfect above 1. gives stretching factor
diagonal aspect ratio: 1. perfect above 1. gives stretching factor
------------
minimum length of an edge in the whole mesh (m) = 845.834129030830
maximum length of an edge in the whole mesh (m) = 3445.40804056081
***
*** max equiangle skewness = 0.644851461933886 in element 4325
of slice 3
***
max deviation angle from a right angle (90 degrees) is therefore =
58.0366315740497
worst angle in the mesh is therefore 31.9633684259503
or 148.036631574050 degrees
max edge aspect ratio = 3.16452595625274
max diagonal aspect ratio = 1.94195278028331
***
*** Maximum suggested time step for simulation = 0.04293954
***
*** max stability = 0.470400000000000
*** computed using VP_MAX = 1600.00000000000
***
that value is below the upper CFL limit of 0.480000000000000
therefore the run should be stable
creating histogram and statistics of mesh quality
histogram of skewness (0. good - 1. bad):
0.0000000E+00 - 5.0000001E-02 27648 81.81818 %
5.0000001E-02 - 0.1000000 0 0.0000000E+00 %
0.1000000 - 0.1500000 0 0.0000000E+00 %
0.1500000 - 0.2000000 0 0.0000000E+00 %
0.2000000 - 0.2500000 0 0.0000000E+00 %
0.2500000 - 0.3000000 0 0.0000000E+00 %
0.3000000 - 0.3500000 0 0.0000000E+00 %
0.3500000 - 0.4000000 1024 3.030303 %
0.4000000 - 0.4500000 2048 6.060606 %
0.4500000 - 0.5000000 0 0.0000000E+00 %
0.5000000 - 0.5500000 0 0.0000000E+00 %
0.5500000 - 0.6000000 1024 3.030303 %
0.6000000 - 0.6500000 2048 6.060606 %
0.6500000 - 0.7000000 0 0.0000000E+00 %
0.7000000 - 0.7500000 0 0.0000000E+00 %
0.7500000 - 0.8000000 0 0.0000000E+00 %
0.8000000 - 0.8500000 0 0.0000000E+00 %
0.8500000 - 0.9000000 0 0.0000000E+00 %
0.9000000 - 0.9500000 0 0.0000000E+00 %
0.9500000 - 1.000000 0 0.0000000E+00 %
exact area: 10336619190.4864
Repartition of elements:
-----------------------
total number of elements in each slice: 8448
total number of points in each slice: 9824
total number of elements in entire mesh: 33792
total number of points in entire mesh: 39296
total number of DOFs in entire mesh: 117888
using single precision for the calculations
smallest and largest possible floating-point numbers are: 1.1754944E-38
3.4028235E+38
Elapsed time for mesh generation and buffer creation in seconds =
2.13852596282959
End of mesh generation
done
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