Why should you consider using a computational fluid dynamics
(CFD) package? After all, CFD is a bit mathematical, isn’t
it - something to leave to a consultant with specialised knowledge
and experience of using this type of software.
Well, not exactly. If you
seek to save money and time on the design of any product where
liquid or gas flow has a bearing on performance or efficiency,
then CFD is a tool not to be shunned. And while the services of
consultants are invaluable to the design community, CFD is becoming
easier to use and designers with complementary computer skills
might be surprised at what they can achieve with current CFD products.
One such is Star CCM+,
a ‘next generation’ CFD code from
CD Adapco Group This code offers what its originator
describes as ‘outstanding
ease-of-use’ thanks
to an object-based, tree-structured GUI, which guides even the most
novice user through the set-up and analysis of a CFD problem.
Unlike conventional GUIs
and their ‘formfilling’ approach,
the Star CCM+ GUI asks the user a sequence of relevant questions
and the solver will not enter the run stage until all have been satisfactorily
answered. Star CCM+ uses a polyhedral cell formation, which is more
processor- and memory-efficient than conventional hexahedral or tetrahedral
meshes. Moreover, this polyhedral structure accommodates any mesh
type, allowing the import of meshes from other products such as Ansys
ICEM, GridGen, Fluent/Gambit as well as CD Adapco’s
own Star-CD advanced CFD solver.
Reducing the user’s
learning curve was one of the key drivers behind the latest release
(5.0) of the Ansys ICEM CFD environment (www.ansys.com). The new
release sees the integration of the hex meshing and post-processing
modules, giving the user a much easier ‘ride’ without
compromising his or her control over the software. New and existing
users will appreciate the new meshing technology, which is a single
unified environment for shell, tetra, prism, hexa and hybrid meshes,
as well as the additional display options, Spaceball support and
hotkeys.
FEMLab (Finite Element Modelling Laboratory)
is a software package from Comsol (www.uk.comsol.com)
for the modelling
and simulation of any physical process that can be described by
partial differential equations (PDEs). A particular strength of
the latest version (3.0a) is its PDE modelling capability, enabling
equations from various fields such as structural mechanics, electromagnetics,
fluid flow and chemistry to be linked and solved all in the same
model - and all at the same time. This is an interesting software
development that does challenge some established specialised packages.
Indeed, if you would like to learn more about this, a number of
benchmark tests have been carried out by independentacademic institutions
and the results are available on the Internet A benchmark of FEMLab,
Fluent and Ansys, for example, isavailable at www.maths.lth.se/na/staff/olivier/
benchmarkreport2.pdf
Perhaps the most popular solution for post-processing
CFD data is Tecplot (http://tecplot.adeptscience.co.uk). We’ve
looked at Tecplot before on this page; it’s a very useful tool
for analysing and plotting data from different sources such as test
results, data from numerical simulations and analyses, and it can
produce outstanding plots and animations. It has strong roots in
the CFD sector, and the developers have recently released a new version
4 of the Tecplot CFD Analyzer, an add-on that provides extensive
capabilities for postprocessing CFD results.
The Tecplot CFD Analyzer boosts productivity by quickly
finding, extracting and processing the critical information. The
module can be used to examine grid quality, perform spatial integrations,
generate particle trajectories, extract flow features and estimate
numerical errors. Use it in conjunction with the latest Tecplot
version 10 and you have a powerful CFD solver with extensive XY,
2D and 3D plotting capabilities, high quality animation, the ability
to automate plotting tasks with layout files and macros, and full
control of the plot to ensure you create exactly the image you
want.
Tecplot also allows you to
view and compare results from other CFD solvers and experimental
data - all in the one tool. Finally, if you want to learn more
about the subject of CFD, there’s
a very good independent organisation called NAFEMS (www.nafems.org)
that can help you.
Do you have any software problems
that Dr Know might be able to help you with? If so contact editor,
Les Hunt (les.hunt@imlgroup.co.uk) who will forward it. We will
publish a selection of problem/solutions in the Dr Know section
of the DPA web site.
Dr
Know's recommended download is the Tecplot 30 day trial version
- download yours today.