2. Lecture Outline
What is Computational Fluid Dynamics?
Advantages of CFD
Limitations of CFD
Applications of CFD
Future of CFD
Summary
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3. What is Computational Fluid
Dynamics?
Computational Fluid Dynamics: A branch of fluid
mechanics that uses numerical methods and
algorithms to solve and analyze problems that
involve fluid flows.
A new branch of engineering, integrating not only
fluid mechanics but also the disciplines of
mathematics and computer science.
Particularly dedicated to the fluids that are in
motion and processes that may include heat
transfer and possibly chemical reactions.
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5. What is CFD? contd..
Physical characteristics of fluid motion can be
described through governing mathematical
equations, usually in partial differential form.
In order to solve these mathematical equations,
software tools developed with high level computer
programming languages are run on high speed
digital computers and numerical solutions are
obtained.
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7. What is CFD? contd..
CFD has also become one of the three basic
approaches that can be employed to solve
problems on fluid dynamics.
Each approach is strongly interlinked and does not
lie in isolation.
Traditionally, both experimental and analytical
methods have been used to study the various
aspects of fluid dynamics.
They assist engineers in the design of equipment
and industrial processes involving fluid flow.
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8. What is CFD? contd..
With the advent of digital computers, computational
(numerical) aspect has emerged as another viable
approach for fluid flow analysis.
Higher processing speeds and shorter lead times have
also contributed towards the acceptance of CFD.
Although the analytical method is still practiced and
experiments will continue to be significantly
performed, the trend is clearly towards the
computational approach for industrial designs.
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9. What is CFD? contd..
Multipurpose CFD programs are gradually earning
popularity.
Such software can be readily employed to solve
numerous fluid flow problems since they are very well
tested and validated by the developers.
Despite the well developed methodologies within the
computational codes, CFD certainly needs more than
just being proficient in operating the said software.
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10. What is CFD? contd..
CFD has become a powerful tool to be employed
either for pure or applied research or for industrial
applications.
Computational simulations and analyses are
increasingly performed in many engineering fields
such as in Aerospace Engineering, Automotive
Engineering, Biomedical Engineering, Chemical
Engineering, Civil and Environmental Engineering,
Power Engineering, Sports Engineering etc.
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11. What is CFD? contd..
Through CFD, extensive knowledge can be
obtained on how components are expected to
perform and to make the required improvements in
design and possible optimization.
CFD is revolutionizing the teaching and learning of
fluid mechanics in most Universities through
visualization of complex fluid flows.
This has allowed students to easily absorb the
concepts of fluid flow and heat transfer through a
Virtual Fluids Laboratory.
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12. Advantages of CFD
With the rapid advancement of digital computers, CFD
has made possible the cutting edge research in fluid
dynamics and heat transfer.
The emergence of CFD as a practical tool in modern
engineering practice is steadily attracting much
interest and appeal.
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13. Advantages of CFD contd..
CFD complements experimental and analytical
approaches by providing an alternative cost-
effective means of simulating real fluid flows.
CFD substantially reduces lead times and costs in
design and production, compared to experimental-
based approach.
Offers the ability to solve a range of complicated
flow problems where the analytical approach is
lacking.
These advantages are realized through the
increasing performance in computer hardware and
its declining costs. 13
14. Advantages of CFD contd..
CFD can simulate flow conditions found in
geophysical and biological fluid dynamics, that are
not reproducible through experiments, such as
disaster scenarios or scenarios that are too huge or
dangerous to be simulated experimentally.
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Indonesian Tsunami of 2004
15. Advantages of CFD contd..
CFD can provide detailed, visualized and
comprehensive information when compared to
analytical and experimental fluid dynamics.
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16. Advantages of CFD contd..
CFD permits alternative designs to be evaluated
over a range of flow conditions.
The utilization of such an approach is generally very
effective in the early stages of fluid systems design.
It may also prove to be significantly cheaper in
contrast to the ever-increasing cost of performing
experiments.
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17. Advantages of CFD contd..
In many cases, where details of fluid flow are
important, CFD can provide detailed information
and understanding of the flow processes.
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18. Advantages of CFD contd..
With market competition requiring a higher degree
of optimal designs and as high technological
applications demand precise prediction of flow
behaviour, experimental methods may be too costly
and hence CFD presents an alternative option.
However, CFD will not soon replace experimental
methods as a means to gather information for
design purposes.
Instead, it is considered as a viable alternative.
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19. Limitations of CFD
In spite of the great potential, some inherent
limitations are there in CFD.
Numerical errors exist in computations and hence
there may be differences between the computed
results and reality.
There is a danger that an erroneous solution may
not correspond to the expected flow behaviour.
Hence, numerical results obtained through CFD
must always be thoroughly examined and validated
before they are fully accepted.
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20. Applications of CFD
As a Research Tool
As a Design Tool
Aerospace and Defence Sector
Automotive Engineering
Biomedical Science and Engineering
Civil and Environmental Engineering
Energy Engineering
Sports Science and Engineering
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21. Applications of CFD contd..
As a Research Tool
CFD can be employed to better understand the
physical events or processes that occur during
the flow of fluids.
These events are closely related to the
phenomena associated with dissipation,
diffusion, convection, heat transfer, boundary
layer interactions, turbulence etc.
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22. As a Research Tool
CFD, similar to wind tunnel tests can be employed as
a research tool to perform numerical experiments.
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23. Applications of CFD contd..
As a Design Tool
CFD is also becoming as an integral part of
engineering design and analysis in prominent
industries.
Companies are seeking industrial solutions through
CFD for the optimization of products and processes
and to predict the performance of new designs even
before they are manufactured or implemented.
CFD has assisted engineers by providing significant
insights into the flow characteristics related to the
equipment & processes.
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24. Applications of CFD contd..
Aerospace & Defence Sector
Computational fluid dynamics has enjoyed a long history of
development and application in the aerospace and defence
industries.
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25. Applications of CFD contd..
Automotive Engineering
CFD has long been an essential element in
automotive design and manufacture.
Has the ability to optimize existing automotive
engineering systems to improve fuel economy,
reduce vehicle emissions to meet strict standards,
improve passenger comfort & durability, and
enhance external aerodynamic performance.
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26. Applications of CFD contd..
Automotive Engineering
CFD modelling has done extensive analysis of the
features of cylinder and combustion chamber of
automobiles and has achieved substantial results.
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27. Applications of CFD contd..
Biomedical Science and Engineering
CFD simulations can provide invaluable information
in predicting the behaviour of systems of the human
body that is extremely difficult to be obtained
experimentally.
Medical simulations of circulatory functions offer
many benefits.
They can lower the chances of possible
complications, assist in developing better surgical
procedures, and deliver a good understanding of
biological processes as well as more efficient medical
equipment. 27
28. Applications of CFD contd..
Biomedical Science and Engineering
Medical images obtained from accurate CT or MRI
scans are converted into geometrical models which
can be subsequently used for advanced CFD flow
simulations.
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29. Applications of CFD contd..
Civil and Environmental Engineering
CFD can assist in ensuring compliance to strict
regulations during the early design stages of
building construction.
To determine the feasibility of a construction,
flow modelling can be performed which provides
insights into the flow behaviour for the proposed
buildings/structures that would not have been
possible only through physical modelling.
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31. Energy Engineering
CFD provides a better understanding of the
equipment and processes within the energy industry.
To maximize return on investment, CFD is being
employed to optimize the turbine blades for
generating constant power under varying wind
conditions in wind power plants.
To meet strict regulations, CFD simulations assist
engineers to identify and improve areas where
deficiencies in power plant design occur.
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32. Energy Engineering contd..
The causes for the ineffective operations can be
rectified in order to reduce emissions and losses
in power plants in a cost effective manner.
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33. Sports Science and Engineering
Aerodynamics of sports balls
Cricket
Golf
Baseball etc.
Design of sports equipment
Optimize the performance of sportsmen/women
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34. Future of CFD
• A revival of the usage of CFD simulations in many
industrial applications witnessed.
• This trend is partly attributed by the rapid evolution
of CFD techniques and models.
• The increasing usage of CFD codes in the industry
is a clear evidence of how demanding practical
problems are now being analyzed by CFD.
• With decreasing hardware costs and rapid
computing times, engineers are increasingly relying
on CFD tools for producing accurate results.
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35. Future of CFD contd..
• Significant advances in virtual technology and
electronic reporting are allowing engineers to
analyze CFD predictions and make necessary
decisions on a given design.
• Application of CFD is gradually moving away from
the academic research into the industry.
• A significant demand for CFD Engineers is
expected in industry and research sector in the
near future.
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