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What is engineering?
Engineering is an open-ended process during which
scientific knowledge is converted to useful products for
the benefit of society
Engineers are problem-solvers; they must assimilate
numerous skills (e.g. math & physics) and resources
(e.g. oceanic data) in order to solve a problem through
means such as the design of a structure, vehicle or
system
In order to perform this, an engineer must be
inquisitive and broadly educated, he or she must be
knowledgeable in the sciences and in the language of
engineering - namely mathematics, and he or she must
be well educated in the fundamental courses common
to all engineering disciplines - courses in: statics,
dynamics, thermodynamics, fluid dynamics, materials,
electrical theory, experimental techniques etc.
With this essential background established, a student
can begin to apply his or her knowledge to a specific
engineering problem - such as the design of a ship or
an offshore structure.
Naval architecture is that field of engineering which
addresses how we can apply our acquired wealth of
knowledge to design, test, build, and operate ships.
All types of ships and boats - recreational to naval,
small to big, operating on or under the sea, sails to
nuclear, etc.
Some of the features of a ship
• A ship is a self-contained entity - it must operate for
extended periods in a very hostile environment
(storm tossed seas, submerged, corrosion).
• A ship has a crew, it is self-propelled, and carries
those systems {electrical generation and distribution,
water and sewage, HVAC, habitability (staterooms,
galley, etc.), cargo handling, weapons, propulsion,
maneuvering, and many others} which are essential to
economically and effectively accomplish its mission or
missions.
• A ship can have a very long service life.
• A ship has to be able to protect itself (navigational aids,
mobility, maneuverability, weapons systems) and, if
necessary, to absorb punishment (watertight subdivision,
double hulls, pumps, and fire fighting).
• A ship is very complex . To design a ship is an extremely
challenging but immensely interesting task. An
undergraduate education in naval architecture will
provide you the tools to begin to pursue this engineering
challenge.
• You will be an engineer, a naval architect, and an
individual who is capable of finding viable economical
and technical solutions to a variety of complex and
open-ended engineering problems. Such as:
• How to safely and efficiently move a variety of cargoes
across the world’s oceans (cruise liners, tankers,
containerships, heavy lift ships, tug-barge units, etc.).
• How to effectively project your nation’s economic,
political, and military objectives across the seas (aircraft
carriers, frigates, submarines, cargo ships, etc.).
• How to best protect your nation’s coastline, resources,
and waterborne trade (patrol craft, buoy tenders, oil
spill response ships, escort tugs, etc.).
• How to safely explore and wisely exploit the abundant
resources found in the ocean’s depths and in its ice
covered areas (drill ships, fishing boats, oceanographic
ships, icebreakers, etc.).
• How to provide better boats and ships for
entertainment, sport, and recreational boating
(excursion boats, casino boats, sailing yachts, motor
yachts, etc.).
SHIPS
Ships are a vital element in the modern world. They still
carry some 95 per cent of trade. In 1994 there were more
than 80 000 ships each with a gross tonnage of 100 or more,
representing a gross tonnage of over 450 million in total.
Although aircraft have displaced the transatlantic liners,
ships still carry large numbers of people on pleasure cruises
and on the multiplicity of ferries operating in all areas of the
globe. Ships, and other marine structures, are needed to
exploit the riches of the Deep.
Although one of the oldest forms of transport, ships, their
equipment and their function, are subject to constant
evolution. Changes are driven by changing patterns of world
trade, by social pressures, by technological improvements in
materials, construction techniques and control systems, and
by pressure of economics. As an example, technology now
provides the ability to build much larger, faster, ships and
these are adopted to gain the economic advantages those
features can confer.
NAVAL ARCHITECTURE Naval architecture is a fascinating and demanding discipline.
It is fascinating because of the variety of floating structures
and the many compromises necessary to achieve the most
effective product. It is demanding because a ship is a very
large capital investment and because of the need to protect
the people on board and the marine environment.
One has only to visit a busy port to appreciate the variety of
forms a ship may take. This variation is due to the different
demands placed on them and the conditions under which they
operate. Thus there are fishing vessels ranging from the small
local boat operating by day, to the ocean going ships with
facilities to deep freeze their catches. There are vessels to
harvest the other riches of the deep - for exploitation of
energy sources, gas and oil, and extraction of minerals. There
are oil tankers, ranging from small coastal vessels to giant
supertankers.
Other huge ships carry bulk cargoes such as grain, coal or
ore. There are ferries for carrying passengers between
ports which may be only a few kilometres or a hundred
apart. There are the tugs for shepherding ships in port or
for trans-ocean towing. Then there are the dredgers,
lighters and pilot boats without which the port could not
function. In a naval port, there will be warships from
huge aircraft carriers through cruisers and destroyers to
frigates, patrol boats, mine countermeasure vessels and
submarines.
Besides the variety of function there is variety in hull form. The
vast majority of ships are single hull and rely upon their
displacement to support their weight. In some applications
multiple hulls are preferred because they provide large deck
areas without excessive length. In other cases higher speeds
may be achieved by using dynamic forces to support part of the
weight when under way. Planing craft, surface effect ships and
hydrofoil craft are examples. Air cushion craft enable shallow
water to be negotiated and provide an amphibious capability.
Some craft will be combinations of these specialist forms.
The variety is not limited to appearance and function.
Different materials are used - steel, wood, aluminium and
reinforced plastics of various types. The propulsion system
used to drive the craft through the water may be the wind,
but for most large craft is some form of mechanical
propulsion. The driving power may be generated by diesels,
steam turbine, gas turbine, some form of fuel cell or a
combination of these.
The power will be transmitted to the propulsion device
through mechanical or hydraulic gearing or by using
electric generators and motors as intermediaries. The
propulsor itself will usually be some form of propeller, but
may be water or air jet. There will be many other systems
on board - means of manoeuvring the ship, electric power
generation, hydraulic power for winches and other cargo
handling systems.
A ship can be a veritable floating township with several
thousand people on board and remaining at sea for several
weeks. It needs electrics, air conditioning, sewage
treatment plant, galleys, bakeries, shops, restaurants,
cinemas, dance halls, concert halls and swimming pools.
All these, and the general layout must be arranged so that
the ship can carry out its intended tasks efficiently and
economically.
The naval architect has not only the problems of the
building but a ship must float, move, be capable of
surviving in a very rough environment and withstand a
reasonable level of accident. It is the naval architect who
'orchestrates' the design, calling upon the expertise of
many other professions in achieving the best compromise
between many, often conflicting, requirements.
The profession of naval architecture is a blend of science
and art. Science is called upon to make sure the ship goes
at the intended speed, is sufficiently stable and strong
enough to withstand the rigours of the harsh
environment in which it moves, and so on. The art is in
getting a judicious blend of the many factors involved so
as to produce a product that is not only aesthetically
pleasing but is able to carry out its function with
maximum effectiveness, efficiency and economy.
Naval architecture is a demanding profession because a
ship is a major capital investment that takes many years
to create and is expected to remain in service for perhaps
twenty-five years or more. It is usually part of a larger
transport system and must be properly integrated with
the other elements of the overall system.
The geography of, and facilities at, some ports will restrict the
size of ship that can be accommodated and perhaps require it to
carry special loading and discharging equipment. An example of
this is the container ship. Goods can be placed in containers at
the factory where they are produced. These containers are of
certain standard dimensions and are taken by road, or rail, to a
port with specialized handling equipment where they are loaded
on board.
At the port of destination they are offloaded on to land
transport. The use of containers means that ships need spend
far less time in port loading and unloading and the cargoes are
more secure. Port fees are reduced and the ship is used more
productively.
The designer must create the best possible ship to meet the
operator's needs. In doing this he must know how the ship will
be used and anticipate changes that may occur in those needs
and usage over the years. Thus the design must be flexible.
History shows that the most highly regarded ships have been
those able to adapt with time.
Most important is the safety of ship, crew and environment.
The design must be safe for normal operations and not be
unduly vulnerable to mishandling or accident. No ship can be
absolutely safe and a designer must take conscious decisions as
to the level of risk judged acceptable in the full range of
scenarios in which the ship can expect to find itself. There will
always be a possibility that the conditions catered for will be
exceeded and the risk of this and the potential consequences
must be assessed and only accepted if they are judged
unavoidable or acceptable.
.
Even where errors on the part of others have caused an
accident, the designer should have considered such a
possibility and taken steps to minimize the consequences. For
instance, in the event of collision the ship must have a good
chance of surviving or, at least, of remaining afloat long
enough for passengers to be taken off safely. This brings with it
the need for a whole range of life saving equipment. The heavy
loss of life in the sinking of the Estonia in 1994 is a sad
example of what can happen when things go wrong. Cargo
ships may carry materials which would damage the
environment. if released by accident. The consequences of
large oil spillages are reported all too often.
Other chemicals may pose an even greater threat. The
bunker fuel in ships is a hazard and, in the case of
ferries, the lorries on board may carry dangerous loads.
Clearly those who design, construct and operate ships
have a great responsibility to the community at large. If
they fail to live up to the standards expected of them
they are likely to be called to account.
Over the years the safety of life and cargo has prompted
governments to lay down certain conditions that must
be met by ships flying their flag, or using their ports.
Because shipping is world wide there are also
international rules to be obeyed. International control
is through the International Maritime Organisation.
The key to unlocking the last frontier on earth lies in the
hands of the ocean engineer. Ocean scientists provide
us with a basic knowledge of the ocean environment, but
it is up to the ocean engineer to apply modern
engineering principles in order to work in this
environment and utilize it more effectively. By blending
the fundamentals of mathematics, physics, material
science, and oceanography with the basic elements of
civil, mechanical, and electrical engineering, the ocean
engineer is able to apply this knowledge to ocean
materials, power systems, acoustics, wave mechanics, life
support systems, and the design of a wide variety of
ocean vehicles and structures.
Ocean engineering is a relatively young, extremely
varied and remarkably exciting field of engineering.
Oceans truly are the last frontiers remaining on earth,
and it is up to us as engineers to find ways to identify,
investigate and utilize ocean and coastal resources while
at the same time protecting them from the destructive
effects of human activities.
While engineering has been around for hundreds of
years, the term "ocean engineering" has been in
existence for only about 50 years. However, there are
certainly a myriad of engineering problems related to
our oceans that have existed for quite some time --
most of which still need attention! And since more
than two-thirds of the earth is covered by water, and
more than 98% of the biological living space exists in
the oceans, wouldn't it make sense if at least two-thirds
of engineers were ocean engineers?
We all know that this is not the case, and those who
choose ocean engineering have quite a collection of
problems to solve ... Ocean engineering is a field of
engineering that has many opportunities within it to
make an impact!
What is Ocean Engineering?
Ocean engineering is one of the most varied engineering
disciplines. The ocean engineering education includes
the standard fundamental engineering courses such as
statics, dynamics, strength of materials, materials
science, thermodynamics, fluid mechanics, along with
other applied engineering courses. Since ocean
engineering encompasses so many different areas and
types of problems, there are many different types of
elective courses offered. Each of these elective courses
strives to utilize and reinforce the fundamental tools
learned, while expanding the problem-solving capability
of each student.
Ocean engineering program includes coverage of the
following disciplines within ocean engineering area
(through elective courses and subject matter with core
and design courses):
Coastal Engineering - Learn the dynamic interaction of
the ocean and its shore
An ocean engineer ...
Develops shore protection systems
Designs harbors and ports
Deals with Civil Engineering issues in the coastal
environment
Offshore Engineering - Learn to design structures capable of withstanding the severe ocean environment Offshore structures include ... Steel jacket structures Concrete gravity platforms Tension-leg platforms
Underwater Engineering - Learn the special requirements of living and working underwater Underwater concerns include ... Life support Work systems Cables, pipelines, shipwrecks, etc.
Environmental Engineering - Learn to protect the
oceans and seas from the harmful effects of
mankind's activities. Also learn to harvest and/or
utilize oceanic resources such as minerals, wave
energy, thermal energy and tidal power.
Environmental concerns include ...
Pollution abatement
Environmental remediation
Ocean resource utilization