The analysis of durability
It is impossible to create high quality products without
thorough analysis of the design ability to hold out loadings
and to function in the right way under the given maintenance
conditions. The optimisation of a product, giving an opportunity
to receive a technological easy design and at the same time
guaranteeing its correct work during the life ñycle is an
obligatory requirement of the market. We optimise not only
the final product, but also manufacturing processes which
are used for its creation. Our engineering analysis includes
calculation of static durability, loss of stability, damage
after any impact, the analysis of vibration, heat transfer,
dynamics of mechanism and other things.
The aim of optimisation is an iterative task when during
the change of design parameters and the subsequent analysis
of its behaviour we achieve the best decision with regard
to the given criteria.
Depending on complexity of a product and wishes of a customer
we carry out the analysis of durability either in MSC\Nastran,
or in a set of Unigraphics modules.
In MSC/Nastran package we carry out decisions of engineering
problems by means of FE-method, which includes:
- The linear static analysis;
- The statistical analysis taking into account nonlinearity
of the material properties and a deformation process (physical
and geometrical nonlinearity);
- The analysis of non-stationary processes taking into
account physical and geometrical nonlinearity;
- Definition of the frequencies and forms of fluctuations
and the analysis of stability;
- The direct and modal analysis of complex meanings;
- The direct and modal frequency analysis caused by casual
exaltation;
- The direct and modal analysis of non-stationary processes
(including the spectral analysis);
- The linear static and frequency analysis taking into
account cyclic symmetry;
- Linear and nonlinear stationary heat exchange;
- Non-stationary heat exchange;
- Aeroelasticity;
- Multilevel superelements;
- Sensitivity of the form and optimisation;
- Acoustics.
MSC\Nastran can be also used for project optimisation.
We can carry out optimisation for problems of statics, stability,
established and unsteady dynamic transients, natural frequencies
and forms of fluctuations, acoustics and aeroelasticity.
For calculation we can also use the software package of
Unigraphics, namely modules:
UG/Mechanisms
With the help of this module we can carry out the complex
kinematic analysis and model virtual behaviour of any 2D
and 3D systems directly in Unigraphics. We can carry out
various stages of an assembly with minimal gaps, options
of a direction definition of contacts imposing and ways
of disassembly. We can analyse interaction of forces, rates
and speedups. The action of forces can be transferred then
into FEA. Further we can use the geometry for accommodation
of connections and forces, for definition of CAM-structures.
With the help of this module we can form an entrance file
for ADAMS/Solver and then carry out a more complex analysis.
The result of this module is a weighting circuit, fixings
of details, and also meanings of loadings and the given
moments, which serve as the initial data for work of UG/Scenario
for FEA module.
Scenario for Structure
We use this module for researches of designs and scenarios
of different variants. The module allows us to manipulate
different variants of a product at the early stages of the
project by means of FE-methods for search of the optimal
design decision.
The preprocessors and postprocessors of Scenario allow designing
a grid of final elements on the basis of the model directly
in Unigraphics. Thus, a grid is associated with geometry
of a detail. We can apply all available in Unigraphics opportunities
of solid elements modelling in order to change parameters
of the analysed model. It gives an opportunity to create
sets of alternative variants or "scenarios".
Strength Wizard
This module, constructed on technologies of master-processes,
provides simple step-by-step procedure of a detail calculation
on static durability. After calculation the system gives
out the answer about a possibility of destruction if the
maximum permissible pressure is given, and shows, where
this destruction will take place.
UG/Structure PE
As a number of calculations has increased with the help
of a FE-pattern and calculations, associated with design
optimisation, rate and accuracy of the decision become more
and more important. Adaptive grids, optimisation, and research
of model sensitivity give us more powerful tool for optimisation.
However, the more difficult calculations are, the more time
and resources they demand. These limitations reduce an opportunity
to use means of the analysis. That is why, we use UG/Structure
PE module for realisation of complex calculations.
UG/Structure PE is not one solver; it is a combination of
three incorporated solvers. UG/Structure PE itself automatically
chooses the most acceptable type of a solver for the analysed
design, and the given task. It guarantees that the best
solver will be applied, which fully uses the resources of
memory, a disk and loading of the processor. As a result,
UG/Structure PE solve the problems of design simulation
quicker than other modern solvers.
Besides, this module works faster and more precise than
traditional solvers; it contains a special adaptive mechanism
of the accuracy control. |
