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Flow Simulations in PLM
The Product Lifecycle Management Gap
The term “Product Lifecycle Management” or PLM is currently on everyone’s lips. It is defined as the task of
consistently using and managing all product-related data that occurs in the development, usage and recycling
phases of a product and across all modifications. Recently, the PLM concept has become firmly established in
industry thanks mainly to the broad-based transition to three-dimensional product models as central data records
for development, production and documentation and the extensive networking of business processes.
Dr. Ivo Weinhold, Product Manager, NIKA GmbH
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Figure 1: Flow simulation with „EFD.V5“, integrated into „CATIA V5“.
Picture: NIKA
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In the product development and product management phases – including the areas of basic research, concept development,
series development, detailing, series management, adaptation development – as well as the immediate definition of
component geometries, complex simulation calculations for physical processes and mathematical functional proofs now
play a central role. Concurrent engineering methods require information about the feasibility and function of alternative
solutions at times in the development process at which important decisions on the details have not yet been made.
Simulation of the physical functions based on the current version of the 3D model data is therefore the only way to
obtain usable information about the anticipated behaviour as an aid to decision making.
Simulation in PLM Environment
However, to ensure that the simulation results can actually be incorporated into the decision making process, they must
be available in a sufficiently high quality to coincide with the rounds of modifications during development. This sounds
somewhat trivial and is self-evident in many areas of simulation of physical functions. This is demonstrated by the
availability of a wide range of simulation software for PLM solutions, which covers various tasks such as strength analysis,
light and acoustic design, vibration analysis, electromagnetic field calculations and much more. These software packages
are directly integrated into a PLM concept and the associated 3D CAD system, for example “CATIA V5” from Dassault Systèmes.
The PLM suppliers provide corresponding development platforms that allow specialised third-party suppliers to adapt their
simulation and calculation technology to the specific conditions of the PLM platform and thus to develop a functioning
solution based on consistency and integration with the original product data.
However, anyone who looks at the issue of PLM in more detail will see that to date there has not been any software available
for simulating flows and heat transfer as part of a PLM concept. And this despite the fact that important functions of a large
majority of products and methods are physically based on or influenced by fluidic or thermodynamic processes in some way and
their design is often of fundamental importance to the value of the product or method.
One reason for this is that, by their very nature, flow and heat transfer processes are much more difficult to understand and
are far less accessible than dimensioning tasks using structural mechanics, for example. Another important reason for this
“PLM gap”, though, seems to be that many suppliers of flow simulation software are unable to satisfy the most important criterion
for process-oriented flow calculations: namely ensuring that calculation projects are sufficiently efficient to deliver high
quality results and keep up with the pace of design modifications under industrial conditions.
To achieve this objective, many of the routine jobs in a simulation project need to be automated and, above all, necessary
activities that require specialist knowledge from a different discipline need to be kept to a minimum. In other words, the
engineer as a user must be able to concentrate exclusively on his task of dealing with the often-difficult technical and
physical issues. Particularly when it comes to flow simulations, this is only possible if new software concepts and new
simulation technologies for flows and heat transfer are developed for use in a process-oriented PLM environment and supplied
as integrated software components for a PLM platform. In the context of PLM integration, the traditional Computational Fluid
Dynamics (CFD) concept has been superseded by the new concept of Engineering Fluid Dynamics (EFD).
Figure 2: Simulated temperature distribution in a projector lamp.
Picture: NIKA
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Requirements for an EFD Concept
The most important key technologies to achieve a functioning implementation of this EFD concept in practice are:
– Seamless integration of the flow simulation software component into the operating philosophy of the PLM system.
In particular, current parametric, feature-based modelling concepts must be extended into the pre and post-processor
data in the calculation project and this data must be displayed, managed and edited directly in the feature tree for
the original geometry. The user interface for the simulation component must also be adapted to match that of the basic
CAD system.
– Direct use of the existing 3D model data in the CAD component of the PLM system, even though the flow space to be
analysed is not normally available as a separate component for grid generation. Separate modelling or derivation of
the flow space is not acceptable on data consistency grounds.
– Support for version design concepts such as design tables, configurations etc. The simulation project must adapt to
modified components and assemblies and support automated processing of numerous alternative versions.
– Automatic generation of an optimum high quality calculation grid for flow simulations (even for extremely complex
assemblies) without special definition by the user that would only be possible with the appropriate expert knowledge.
– Reliable modelling of complicated flow phenomena, such as boundary layer effects, laminar and turbulent areas in a
model or compressible gas flows, with the entry of just a few practical model parameters.
– Robust solution of the non-linear equation systems that are always analysed in flow simulations without artificial
stabilisation measures that would require extensive knowledge of computational mathematics to use. This point is often
underestimated in practice, but in many cases is crucial to the success or failure of a calculation and is therefore a
critical productivity factor for every simulation project.
Closing PLM Gaps
The “EFD.V5” flow simulation software from NIKA, Figure 1 and Figure 2, closes the flow simulation PLM gap for CATIA V5
for the first time. The program was developed on the “CAAV5” platform and meets the specified requirements for process-oriented
flow simulations within the PLM concept from Dassault Systèmes. As EFD.V5 is based on NIKA’s tried and tested EFD technology,
Figure 3, numerous proven modelling functions are available for immediate use with CATIA V5 product models. For the first time,
this provides an opportunity to efficiently process a large number of routine tasks relating to the flow calculation and to
relieve the burden on the CFD specialists in the calculation department. The software also enables flow calculations to actually
be used to support development, in fact the principle functions of a possible solution can be demonstrated using convincing
simulation results at a very early stage – for example in the quotation phase.
Figure 3: Trend towards the Engineering Fluid Dynamics concept.
Picture: NIKA
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