NX Nastran V11.0  Novedades (Agosto 2016)
Una nueva versión del “solver”
de Análisis por Elementos Finitos NX NASTRAN V11.0 está
disponible en el mercado mundial desde el pasado mes de Agosto 2016, la cual ya
viene integrada con la última versión de FEMAP
V11.3.2 disponible para descarga en Septiembre de 2016.
La lista completa de mejoras y correcciones está
disponible para su consulta en el NX Nastran 11.0 Release Guide,
accesible desde FEMAP desde el menú HELP > NX
NASTRAN:
A quick review of enhancements includes:
Dynamics …
 Shell and Solid Composites in Random
Analysis: Beginning in NX Nastran 10, you could include shell
and solid element composites in the frequency response solutions SOL108 and
SOL111 for a random analysis. However, crosspower spectral density and
crosscorrelation functions were not supported. In NX Nastran 11, a new RCROSSC
bulk entry is available to request crosspower spectral density PSD and
crosscorrelation functions for ply stress responses on 2D Shell and 3D
Solid composites element .
 Modal Frequency Response Improvement:
When structural or viscous damping is included for a modal frequency
response solution (SOL111), the orthogonality property of the modes
generally does not diagonalize the stiffness or damping matrices.
Consequently, the equations of motion are typically coupled. Performance
methods are available to solve these problems more efficiently.
 For example, the incore FRRD1 method was
introduced in NX Nastran 9, and is supported in a serial or SMP run.
However, the memory requirement increases quickly with this method as
the number of modes and number of SMP cores increase.
 Beginning in NX Nastran 11, an incore FRRDRU
method is now available to solve these problems efficiently and with
moderate memory usage. The new method is supported in a serial, SMP, or
a DMP run.
 Performing Multiple Random Analyses:
In NX Nastran 11, the ANALYSIS case control command now includes the RANDOM
subcase type for SOLs 108 and 111. With the new RANDOM type, you can
streamline the process of performing multiple random analyses with the
RANDOM and optionally RCROSS case control commands over frequency response
subcases of the same frequencies.
Acoustics …
 New Automated Matched Layer modeling for simulating
vibroacoustic exterior radiation.
 Added several porous material models for modeling sound
absorptive materials.
 Microphone point modeling allows recovery of sound
pressure at any location either interior or exterior to an acoustic mesh.
 New output request for acoustic intensity, acoustic
velocity, and acoustic power.
 New weak coupling option to solve vibroacoustic
solutions more efficiently.
Rotor Dynamics …
 Mode Filtering: Beginning
with NX Nastran 11, you can use strain energybased criteria and kinetic
energybased criteria to identify the modes that have minimal impact on the
dynamic response in a SOL 107 or SOL 110 complex eigenvalue analysis in
rotor dynamics. You can omit these modes from the list of modes that are
tracked throughout the remainder of the rotor dynamics analysis. Because
modes of little importance are eliminated, the analysis results produce a
less cluttered and potentially more meaningful Campbell diagram.
 Complex Eigenvalue and Frequency Response
Analysis Enhancements: For frequency response and complex
eigenvalue rotor dynamic analysis, you can now do the following:
 You can include gyroscopic and circulation terms in
the mass, damping, and stiffness matrices when the analysis is performed
in the fixed reference system by specifying the new RLOOPNEW parameter.
 You can list a rotor in the REFROT field of the
ROTPARM bulk entry to designate it as the reference rotor.
 Load specification options for maneuver
load analysis: In earlier versions of NX Nastran, your only
options for specifying the inertial loads that result from angular motion in
a SOL 101 maneuver load analysis were the RFORCE and RFORCE1 bulk entries.
The only difference between them is that RFORCE applies the loading to the
entire model and RFORCE1 applies the loading to a subset of the model that
is defined by a GROUP bulk entry.
 With NX Nastran 11, the new RFORCE2 bulk entry
gives you a third option. The RFORCE2 bulk entry is similar to the
RFORCE entry in that it applies the loading to the entire model.
 However, it differs from RFORCE in that you can
optionally exclude either the gyroscopic or centrifugal forces that
result from the angular motion of the model. To exclude these forces
from the loading, specify the appropriate value in the GYROP field of
the RFORCE2 bulk entry.
 Synchronous Modes in Complex Modal
Solutions: Beginning with NX Nastran 11, you can optionally
solve for synchronous modes only in a SOL 107 or SOL 110 complex eigenvalue
rotor dynamic analysis. To do so, specify NUMSTEP = 0 on the ROTORD bulk
entry and include PARAM,ROTSYNC,YES (default) in your input file. If you
specify NUMSTEP = 0 and PARAM,ROTSYNC,NO, no analysis is performed.
 Expanded Support for Coupled Solutions:
In rotor dynamic analyses, timedependent coupling terms can arise in the
equation of motion when rotors or the supporting structure are
unsymmetrical. In versions prior to NX Nastran 10, these coupling terms were
always excluded from the equation of motion. With NX Nastran 10, the
software allowed you to optionally include the coupling terms in the
equation of motion for SOL 107, 108, and 109 rotor dynamic analyses only.
 Beginning with NX Nastran 11, your ability to
include timedependent coupling terms in the equation of motion is
expanded to also include SOL 110, 111, and 112 rotor dynamic analyses.
 The procedure you use to include coupling terms in
a SOL 110, 111, or 112 rotor dynamic analysis is identical to the
procedure that you use to include the coupling terms in a SOL 107, 108,
or 109 rotor dynamic analysis. Specifically, you use the ROTCOUP
parameter to trigger the inclusion of the coupling terms in the equation
of motion, and you use the PHIBGN, PHIDEL, and PHINUM parameters to
specify the azimuth angle range for the solve.
 Expanded Support for Superelement Style
Reduction of Rotors: NX Nastran 10 provided you with the
ability to apply superelementstyle reduction to rotors. However, this
capability was limited to SOL 107 direct complex eigenvalue analysis in
rotor dynamics.
 Beginning with NX Nastran 11, this capability is
expanded to SOL 108 direct frequency response analysis and SOL 109
direct transient analysis in rotor dynamics.
 Superelement Reduction of Support Structures:
Beginning with NX Nastran 11, you can model the stationary portions of a
rotor dynamics model as external, internal, or partitioned superelements.
You use the same procedure and NX Nastran user inputs that you would if the
model were not a rotor dynamics model.
Multistep Nonlinear (SOL401) …
 Cyclic Symmetry: A new cyclic solution
method is available in SOL401. The new method takes advantage of cyclic
symmetry to reduce the time needed to create and solve a full 360 degree
model. To use this method, you create a 3Dsolid element model that
represents a fundamental segment. The fundamental segment represents a
structure that is made up of N repetitions, where each repetition can be
obtained by rotating the fundamental segment an angle that is an integer
multiple of 2π/N.
 Fourier Harmonic Solution: A new
Fourier normal modes subcase is available in SOL 401 for models which
include axisymmetric elements. The subcase is designated with the
ANALYSIS=FOURIER and HARMONICS=N case control commands in the subcase.
 User defined material support.
 New cohesive element for modeling delamination of
composite materials.
 New damage material model for modeling failure of plies
in composite elements.
 Time unassigned loads can now be ramped over a subcase.
 Time assigned enforced motion loads can now be more
efficiently applied for time dependent spatial enforced motion.
 Initial StressStrain: The
option to define an initial stress or strain condition is available on all
elements in SOL401 except for plane strain elements, generalized plane
strain elements, solid composite elements, and rigid elements. Stress or
strain can now be applied as an initial condition to allow modeling of
residual stress effects.
 Contact sets can now be changed between subcases.
 Support gradual application of contact loading by
incrementing the defined offset distance.
 Sliding Glue: A new sliding
glue option is available for both surfacetosurface and edgetoedge glue
by defining the new parameter setting SLIDE=1 on the BGPARM entry. Sliding
glue includes a normal stiffness, but no tangential stiffness. The new
option is supported for GLUETYPE=2, allowing tangential sliding in glue
connections.
 Bolt preload forces can be sequenced over a single or
multiple subcases.
 Bolt preload can be applied as displacement or strain
or load.
 New bolt output result.
 MAT11 materials can be used for 2D solid elements
instead of MAT3 elements to support torsional stiffness in axisymmetric
models.
 Displacement response at user defined locations can be
viewed in the solution monitor.
Elements …
 New chocking element (SOL 401 only) supports modeling
of axisymmetric systems that are composed of segmented wedges. Depending on
loading the gaps between the segments are open or closed changing the
behavior from plane stress to axisymmetric respectively.
 Support for MAT11 with 2D Axisymmetric
Elements and 2D Solid Elements: Beginning with NX Nastran 11,
as a recommended practice, use MAT11 bulk entries to define orthotropic
material properties for axisymmetric elements and 2D solid elements.
Axisymmetric elements include CCHOCKi, CTRAX3, CQUADX4, CTRAX6, and CQUADX8
elements. 2D Solid elements include CPLSTNi Plane Strain and CPLSTSi Plane
Stress elements. In earlier versions of NX Nastran, you use MAT3 bulk
entries to define orthotropic material properties for CPLSTNi, CPLSTSi,
CTRAX3, CQUADX4, CTRAX6, and CQUADX8 elements. However, MAT3 bulk entries
are not supported for use with the chocking elements that are being
introduced in NX Nastran 11.
 Element Geometry Checks: For
NX Nastran 11, the following changes have been made to the element geometry
checks:
 Usercontrolled element geometry checks are
supported for the new cohesive elements CHEXCZ and CPENTCZ, and the new
chocking elements CCHOCK3, CCHOCK4, CCHOCK6, and CCHOCK8.
 The edgepointincludedangle (EPIA)
usercontrolled element geometry check is available as a separate check.
It is no longer a part of the edgepointlengthratio (EPLR)
usercontrolled element geometry check. The EPIA check is valid for the
solid elements CHEXA, CPENTA, CPYRAM, and CTETRA, and the cohesive
elements CHEXCZ and CPENTCZ.
 For CQUAD8 and CTRIA6 elements, system cell 635 is
available for you to change the maximum allowable angle between normals
to corner grids for the EPLR check.
Advanced NonLinear …
 Support separation distance as output for contact
analysis.
 Support DTEMP card for time modeling time dependent
temperature spatial field.
 Support acceleration component of rotation RFORCE load.
 Support applied load as an output result.
 Support output of ply failure and strength ratios for
composite shell elements.
Topology Optimization …
 A new NX Nastran Topology Optimization product is
available for solutions linear static (SOL101) and modal analysis (SOL103).
It is independent of SOL 200 and has its own inputs and license requirement.
The capability works within a single overall objective, for example,
minimizing mass, along with one or a number of constraints, for example,
limiting displacements at specific grids.
Numerical Performance …
 Efficient unsymmetric linear solution for friction in
SOL 401.
 Improved iteration strategy and other performance
improvements for SOL 401.
 DMP support for cyclic and axisymmetric harmonic
solutions.
 Improved SOL 111 performance for models with low rank
damping.
 RDMODES can be applied to solve for fluid modes in SOL
103 and 111.
 Improved performance of dynamic loads (FRLG) module for
certain large models.
Miscellaneous
 LP64 and ILP64 Executables (Final Release
for LP64 Executable): NX Nastran 11 is the last release for
the LP64 executable, only the ILP64 executable will be available in NX
Nastran 12.
 Two 64bit executable types have been provided
since the ILP64 type was first introduced in NX Nastran 4.
 LP64 is the original 64bit
executable. You can allocate up to 8 GB of RAM with this executable.
 ILP64 is the executable first
introduced in NX Nastran 4. Practically speaking, you can allocate as
much RAM as your machine supports with this executable.
 Convert 64bit XDB File to 32bit:
The CONVERT_TO_XDB_32 utility is now available to convert a binary
results database file (XDB) produced by the ILP64 version of NX Nastran
into a binary results database file compatible with that produced by the
LP64 version of NX Nastran. The utility is available in the NX Nastran 11
installation.
Saludos,
Blas.
 NOTA:
FEMAP V11.3.2 lleva ya
incluido en el DVD de instalación la nueva versión de NX
NASTRAN V10.0
SÍGUENOS
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