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September 2, 2010
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Welcome to ASCGENOA.com
The Leading Software Solution for Material and Structural Failure Analysis
Quick News & Press Release
GENOA 4.4 Released
NANO Capability Introduced
New PFA Unit Cell
New MCO Unit Cell
Issue #18 - 7/13/2009
Numerical Approach to Determine Crack Path and Delamination Growth in Composite Structures
Issue #16 - 10/20/2008
Material Qualification and Certification Determine Allowables by Means of Virtual Simulation Combined With Limited Testing
Issue #15 - 6/10/2008
Predicting Post-Buckling Response and Ultimate Failure of Composite 2-Stringer Panels
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Getting Started with GENOA
What
information is needed to start running GENOA?
The process is simple. Once GENOA is installed
on your PC or workstation, just import a finite
element model (i.e. NASTRAN) to get started, or
use one of the examples from the examples/verification
library.
Are
any support libraries required for running GENOA?
You must have Java 1.5 installed on your PC or
workstation in order to run the main GENOA GUI
application. This application also requires Java
3D for all of the 3D graphics. This can be downloaded
free from a link provided with the GENOA software.
What
are the benefits of using Java and Java3D?
Java provides a platform independence environment
for GENOA to run on and is heavily supported by
the major OS platforms in the market today including
HP, SUN, SGI, Windows, and Linux. Another reason
for using Java is our current research in Collaborative
Virtual Testing (CVT) that allows remote users
to log into a central GENOA server using internet
browsers with a Java plug-in embedded as an interface.
Does
GENOA have its own built-in material library?
Yes, GENOA comes with a sample material library
in a form of databank that contains constituent
properties for fiber and matrix and lamina properties
of typical composites and metals.
What
type of documentation is made available to GENOA’s
users?
Documentation includes: 1) User’s Manual, 2) Theoretical
Manual, 3) Verification Manual, and (4) Step-By-Step
Manual.
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Capabilities & Areas of Applications
What
are the major capabilities of GENOA?
GENOA is used for assessing the durability and
damage tolerance of metallic and composite structures.
Several composites architectures are available.
They include:
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Filament
winding |
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Braid |
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Weave |
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Stitched
2D/3D |
Other
capabilities of the software are:
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Probabilistic
Design |
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Time
Dependent Reliability |
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Random
Fatigue |
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Progressive
Failure Dynamic Analysis (PFDA) |
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Progressive
Failure Optimization (PFO) |
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Virtual Testing |
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Virtual
Crack Closure Technique (VCCT) |
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Discrete
Cohesive Zone Model (DCZM) |
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Power
Spectrum Density (PSD) |
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Material Constituent Analyzer (MCA) |
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Material Uncertainty Analysis (MUA) |
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Material
Characterization Optimizer (MCO) |
What
are typical areas of application of GENOA?
GENOA is ideal for aerospace structures, pressure
vessels, cryogenic storage tanks, turbo machinery,
automotive applications (i.e., crash and crush
problems, and chopped fibers), virtual testing,
manufacturing simulation, construction projects,
sporting good design, and biomedical applications.
Does
GENOA have pre- and post-processing capabilities?
Yes. GENOA utilizes an advanced post- and limited pre-processor to set up the input data and post processors to:
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Pre-Processor |
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No Mesh Generator: FE models can be imported from NASTRAN; ABAQUS or ANSYS |
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The material properties and ply schedules, thermo-mechanical boundary and loading conditions can be edited or defined from scratch using GENOA pre-processor |
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Surfaces, node sets and several contact can also be defined in GENOA pre-processor |
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FE models can be easily set/modified for static, fatigue, impact or other type analysis |
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Post-Processor |
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Output data |
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Animate output |
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Produce contour plots of stresses, strains, and displacements |
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Damage progression and fracture animation |
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Detailed anatomy of damaged plies and associated failure modes |
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Energy release rate plots |
Can
GENOA be used for general structural analysis?
Yes, GENOA can perform: static, buckling, dynamic,
modal, fatigue (low and high cycle), creep, impact,
and random vibration.
Can
GENOA be used to predict damage progression in
buckled structures?
Yes. GENOA can be used to predict damage progression
in buckled and post-buckled structures.
What
type of loadings can GENOA handle?
GENOA is devised to handle static (force, pressure,
and edge traction), body force (centrifugal),
time dependent, and temperature loading.
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Modeling and Finite Element Analysis in GENOA
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What does a typical GENOA model look like?
A typical GENOA model will contain finite element description (nodes, elements, loads and boundary conditions), ply schedules and material specifications. For example, starting with a traditional NASTRAN finite element model, the GENOA graphics user interface (GUI) will generate for you the composite ply schedules and the fiber/matrix/interface or lamina properties.
What
is a ply schedule?
A ply schedule specifies the composite architecture
at selected nodal locations in the structure.
In the ply schedule, you may assign different
materials for different plies and the appropriate
composite architecture. For each ply, manufacturing
details are specified, such as ply thickness,
ply orientation, fiber volume fraction, and void
volume fraction. The GUI in GENOA is designed
to assist the user in making the selections.
How
do I supply the material properties in GENOA?
The material properties are assigned in a databank.
Just make sure that the material selected for
a ply schedule has associated properties in the
databank. The material properties can be specified
as fiber/matrix/interface constituent properties
or as lamina properties.
Can
GENOA handle finite element models from other
commercial software?
Yes, GENOA is designed to import models developed
for or by other programs such as MSC NASTRAN.
Additionally GENOA allows you to import models
from other programs, such as MSC MARC, LSDYNA,
ABAQUS, and ANSYS. GENOA ensures that the translation
process is inclusive of all options selected by
the user.
What
are the main criteria for ply damage?
Ply damage criteria include:
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Ply failure occurs because the fiber strength or ply strain limits have been exceeded
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Matrix failure due to transverse tensile |
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Transverse
compressive, or shear failures. In such event,
only the matrix stiffness is degraded and
the longitudinal stiffness of the fiber is
retained |
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Modified distortion energy (MDE) |
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Relative rotation |
Does
GENOA have its own finite element analyzer?
Yes, GENOA has its own finite element analyzer. The solution is obtained using a dedicated module in GENOA. The FEM analysis is based on well established mixed iterative techniques. Its library of elements is comparable to those of commercial codes.
What
if I wish to have the FEM analysis done by other
programs?
GENOA offers its users the option of utilizing
commercial codes such as MSC NASTRAN, MSC MARC,
LSDYNA, ABAQUS, and ANSYS as the finite element
solver. The interface between GENOA and the other
programs is automatic. No user interference is
required. The user selected FEM solvers will be
used to supply GENOA with the generalized stresses.
The GENOA processors update the FEM model as needed
based on damage progression analysis.
Can
GENOA handle non-uniform geometry?
Sure, GENOA is designed to accommodate all types
of geometry. It can also easily handle thickness
and step changes by assigning appropriate ply
schedules to critical regions.
Are
there any limitations on the model size in GENOA?
No, there are no limitations. The model can be
of any size.
Are
there any limitations on the number of ply schedules
in GENOA?
No, there are no limitations. GENOA can handle
any number of ply schedules.
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Durability & Damage Tolerance
How
is the damage progression evaluation performed
in GENOA?
GENOA judiciously combines the following disciplines: (1) composite micro and macro mechanics, (2) finite element analysis, (3) material degradation, (4) damage tracking/accumulation, and (5) fracture.
What
is damage initiation load?
Damage initiation load is the load that causes
the first ply damage. Properties are degraded
automatically once damage occurs.
What
are the main criteria for ply damage?
Ply damage criteria include: ply failure because the fiber strength or ply strain limits have been exceeded, matrix failure due to transverse tensile, transverse compressive, or shear failures. In such event, only the matrix stiffness is degraded and the longitudinal stiffness of the fiber is retained, modified distortion energy (MDE), and relative rotation.
How
is ply delamination considered in GENOA?
Ply delamination is considered to be due to long
compressive failure, out of plane shear failure,
relative ply rotation, or normal tensile failure.
How is equilibrium established after damage
growth?
Equilibrium is established when the structure
does not sustain any additional damage under the
present applied load. Material properties and
geometry are updated at each establishment of
equilibrium.
What
constitutes fracture initiation in GENOA?
When all the plies at a particular nodal location
have sustained fiber damage and cannot carry any
load, nodal fracture is initiated.
When
is an element removed?
When two nodes within one element are fractured
that element is eliminated. The model is re-meshed
automatically.
What
is damage tolerance in GENOA?
Damage tolerance is defined as the additional
load that the structure can withstand from the
point of damage initiation up to structural fracture.
Describe
simulation of crack initiation and growth to failure.
Progressive fracture involves detailed tracking
of damaged nodes, detailed representation of a
unit cell to track crack initiation, the sequence
of growth to failure, and breakage (in matrix,
interface, or fiber) within the unit cell.
Can
GENOA perform D & DT of sandwich panels?
Yes, GENOA is ideal for D & DT of sandwich panels.
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Troubleshooting and Installation Problems
1)
GENOA won't start up when executing "genoa"
from the command line or double-clicking the icon.
GENOA's GUI requires Java and Java3D for its user
interface. Please be sure that Java 1.5 minimum
and Java3D 1.3.1 minimum are installed.
2)
After the GENOA screen appears upon start-up,
a dialog displays "JAVA3D is not installed
or has been corrupted. Please re-install Java3D
before proceeding." I thought Java3D was
installed on my system already.
Sometimes the Java3D on your system can be corrupted
due to automatic updates of Java 1.5+ or other
system events. To easily solve this, just quickly
re-install Java3D only. If this is a first time
installation of Java, please be sure to install
Java first and then Java3D second.
3)
I installed Java3D 1.4 or Java3D 1.5 and GENOA
seems to crash before showing the FEM graphics.
What's the problem?
Unfortunately Java3D 1.4 and 1.5 both require
OpenGL Version 1.2 as a minimum from your video
card driver where before Java3D 1.3.1 required
OpenGL Version 1.1 minimum. There are two solutions
to this problem:
1) Install an updated video card driver from your
video card manufacturer's website that has OpenGL
Version 1.2 capability.
or
2)
Un-install Java3D and install the earlier Java3D
1.3.1 version.
Some
systems will have Microsoft's default OpenGL Version
1.1 as their only graphics support. Therefore
they will need to install Java3D version 1.3.1.
4)
How much memory is recommended for GENOA?
It is recommended to have a minimum of 1 GB of
RAM for GENOA to effectively run the analysis
jobs.
5)
The file loading and graphics seem to be very
slow in GENOA.
When
double clicking or executing "genoa",
the following command is executed:
java
-mx512m -ms512m -jar "%GENOA%\genoa.jar"
where
the 512 represents the minimum memory stack that
is allocated for Java in the GENOA GUI. This file
can be found by editing the "genoa"
file in the "bin" directory of
where GENOA is installed. To increase the memory
allocation, change the number "512"
to a higher number such as:
java
-mx1000m -ms1000m -jar "%GENOA%\genoa.jar"
Be
sure to save the "genoa" file and try
to run GENOA again to hopefully see faster results.
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