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Newsletter issue
No. 2
SNAME - UNIWA section
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SOME 2021: 7th INTERNATIONAL SYMPOSIUM
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 Finally, the time has come for SOME 2021!
The 7th International Symposium on Ship Operations, Management and
Economics (SOME), is a Virtual Conference that will take
place at 6-7 April and will bring together ship operators,
technical managers, naval architects, marine engineers, academics,
students, classification societies and marine transportation
policy-makers to discuss important issues for the maritime industry.
In
SOME 2021, state of the art R&D projects, academic papers and
applied operational solutions will be presented to kickstart
interesting discussions about important issues of the maritime
industry and also promote new business opportunities. Its 2-day program is scheduled to
comprise keynote speeches and presentations given by key players from
the industry.
The Virtual Conference will have 2 Keynote Speeches and 5 Sessions:
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Session I: Design & Fabrication
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Session II: Digitalization, Computers & Shipping
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Session III: Operations & Emissions
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Session IV: LNG Vessels
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Session V: Legal, Financial & Regulatory Aspects
Stay tuned, as detailed SOME
agenda and detailed information about the event will be published
soon at SOME webpage.
***Sponsorships
opportunities are available by contacting the organizers.
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SNAME
UNIWA – ISALOS.NET WEBINAR
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We
are happy to announce our 1st Webinar in collaboration
with Isalos.Net. It will be
held in April, and it will be addressed to the University of West
Attica Students and generally to Students of other Universities
that are interested in the Webinar topic. A lot of Students have
already shown interest to participate and also learn more about
SNAME.
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SNAME
UNIWA WEBSITE
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We
are happy to announce that our new website is about to become a
fact! We are already under discussions with CRONUS WEB
which is the Web Design company that sponsors, produces and
delivers our informative content through this newsletter to all its
recipients. CRONUS
WEB will take over and sponsor our new website and the
project will begin soon.
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New device: Corrosion Behaviors of Carbon
Steels in Artificially Simulated and Accelerated Marine Environment
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ESG
published very interesting research, about the development of a new
device to simulate and accelerate marine erosion, intending to study
erosion in various marine zones. The device is great, as it has an
excellent simulation of the main parameters and conditions in various
maritime zones, as well as very good acceleration performance.
Purpose: This device was made to perform
operations, analysis, and study of the wetting-drying alternation,
simulation of different erosion zones in the sea, simulation of
various corrosive environments such as the atmosphere, splash, tide,
and immersion zone with quite high reliability. This is possible as a
very good simulation of the natural marine environment is achieved.
It can show significant results in a very short period and this is
particularly important for the development of marine
corrosion-resistant materials.
The structure of the Test device: The
main structure of the device consists of a large experimental tank, a
water supply tank, and the main control panel. To these, two tanks
with a peristaltic pump were added. Also, an afloat and a level meter
were placed respectively in the experimental tank for precise control
of the tidal area. Also inside the experimental tank were fixed
sample slots and rotating oars that act as components for large waves
and splashes.
Experimental operating procedure: The process to do this
study is long and all treatments require a specific time and specific
modifications. The water level, the rotation speed of the propellers,
the temperatures that must be present, the selection of the thickness
and the processing of the steels as well as their subsequent
preservation and processing are some of the procedures that are followed,
which as we mentioned, must be absolute. The time of the whole
process that followed the device in its first study lasted 10 days
but brought very accurate and reliable results.
This device follows a very interesting and important acceleration process.
By always having the samples in wet conditions, the temperature is
the main factor of influence. The higher the temperature, the faster
the reaction (as well as the dry-liquid exchange). For this reason,
the temperature at which the device performs the process is higher
than the actual temperature of the seawater and thus they quickly
achieve the corrosion reaction they want. Depending on the band, some
situations grow accordingly for the device to achieve the desired
corrosion acceleration, such as the wave intensity and the frequency
of tidal fluctuations.
Results and study: Initially, it showed
that carbon steel products in the immersion zone have more external
rust and in the atmosphere zone, the products are compact. The rate
of corrosion of carbon Q235 in the atmospheric zone is minimal
because it is not directly exposed to seawater.
As for the tidal zone, the corrosion rates of carbon steel are higher
than those in the sinking and atmospheric zone. More specifically,
the marine tidal zone also suffers from dry-liquid alternation, where
there is also enough oxygen, which makes it much more corrosive than
the sinking zone. However, in the marine splash zone, the high
frequency of dry-liquid exchange, combined with abundant oxygen and
the shock waves makes it the most serious zone in the issue of
erosion.
An object of
study that is important in the article is that with this device they
managed to study in detail with ease and fast results both the outer
and the inner layer of rust that formed in each zone, but also the
color and the concentration of ions and in two layers. The outer zone
is easily removed but in contrast to the inner zone, where rust is
more difficult to remove as a metal substrate is created. After
carefully studying the findings of the device, analyzing the rate of
corrosion and surface morphology, they came to the very important
conclusion that α-FeOOH is a solid and
stable substance that can effectively inhibit corrosion.
With the device, using the XRD drawings, they saw that the rust
formed on carbon Q235 is essentially the same in different corrosion
zones.
By Marios Chalaris
(source : http://www.electrochemsci.org/papers/vol12/120201216.pdf )
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Transverse
metacentre and initial stability
In
figure 1.1 a ship floats originally at
waterline W0L0. Due to an external force, which is
then removed, the ship rotates through a small angle at waterline W1L1. Assuming all the weights off
the ship are not free to move, the rotation of the ship does not affect
the ship’s center of gravity position ‘’G’’, but it forces the wedge W0OW1
to emerge from the sea and the wedge L0OL1 to
immerse in the sea. The volume of the immersed and the emerged wedges
is equal. This causes the underwater shape of the ship to change and
the center of buoyancy moves from B0 to B1. The
point at which the vertical line passing through the center of buoyancy
and intersects with the original vertical line is termed as the
‘’transverse metacentre’’. For small
inclinations the metacentre can be taken as
fixed in position. ‘’GZ’’ is the perpendicular on to B1M
drawn from G and it is termed as the ‘’righting lever’’. The weight is
acting downwards and the buoyancy force of equal magnitude is acting
upwards. These two forces are not in the same line, as a result a
couple W x GZ is formed. This couple creates a moment termed as
righting moment which is equal to the ship’s righting lever multiplied
by the ship’s displacement (MR=GZxΔ). This
moment indicates the ship’s tendency to resist inclination and forces
it to restore its original position. GM is termed as metacentric height
which is equal to (GM= GZ/sinφ) and
it is an indicator for the ship’s stability. Increasing the GM for the
same ship’s displacement means better stability. This can be achieved
for example if the ship’s center of gravity is lowered. However, as the
GM is increasing the ship will be forced to restore its original
position faster and more violently. This situation in the one hand
improves the ship’s stability but on the other hand might cause a
problem for the passenger’s comfort.
The position
of the center of gravity and the metacentre
will indicate the initial stability of the ship. There are three
different circumstances, which are described below.
·
It is obvious that in figure
1.2 the metacentre ‘’M’’ is above the center
of gravity ‘’G’’ thus a positive righting lever is created end the ship
tends to restore its original position. Ιn
this condition the ship is said to be in stable equilibrium.
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In figure 1.3 the ship’s center
of gravity and metacentre are in the same
location. As a result no righting lever is created thus when the
external force is removed the ship will remain in the inclined
position. The ship is said to be in neutral equilibrium.
·
Last but not least, in figure
1.4 the new position of the centre of
buoyancy, ‘’B1‘’is left of the point ‘’G’’, then the metacentre is below the ship’s center of gravity at
the original vertical line. In this case the righting lever is negative
and the overturning couple formed by the buoyancy force and the weight
of the body tends to capsize the ship from its original position. The
ship is said to be in unstable equilibrium.
  
By Konstantinos
Tsourekas
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Maritime people in pandemic’s net
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While the whole world is dealing with covid-19 pandemic,
maritime couldn’t be intact. Many are the ways that this sector
is affected, meaning that shipping has to deal with various problems,
regarding economy. For instance, the cruise industry has found
itself in a severe situation, as both crew and passengers are
stranded and many cruise ships, unable to sail, are being
scrapped. Administration of the ships is also a tricky problem,
factoring in that each country obligates to different
regulations according to current epidemiological data. It is an
undeniable fact that the physical problems of shipping are much
more and hard to list, but this is not what this article is
about. Covid-19 disease
has affected maritime in another significant way, which is the
anthropocentric way. This problem could be initially parted in
two. On one hand, people working ashore and on the other people
working overboard.
As for the first group of people, it was essential for
them to adjust the safety regulations, improving the sanitary
conditions on the vessel and finding ways to prevent crew and
passengers from being exposed to the virus. So, new regulations had to be
made, in order to provide Covid-19 tests for each person on
deck and consequently enact preventive health measures, until
the vaccines are provided, improving significantly this
situation. As well as, preventing the spread of the virus, many
employees such as technicians and engineers, faced difficulties
in approaching the ships, as they couldn’t travel neither
abroad, and in some cases, nor within the country. This led to
the need of conducting distance surveys with technology
contributing to take physical presence’s place. Regarding the
employees in shipping, they had to work from home obligating
with the preventive health measures. A closer look to all these
differentiations in the daily routine of employees would prove
that it offers a less social and distant way of live, causing
angst to their majority.
As for the people working on board, the obstacles are
many. Many, not only crew but also passengers, are quarantined,
once a case of the illness is detected among them. Others are
quarantined preemptively, considering that in this way the expansion
of the virus will be prevented. For this cause, a number of
other regulations were made. For instance, when a ship lashes,
crew isn’t always allowed to go ashore, depending on port’s as
well as each country’s restrictions. Some are allowed to go ashore,
as long as their temperature allows it and no signs of illness
are appeared. Others cannot leave the ship, unless service
requests it. So, the general idea of reducing the Maritime’s
contacts appeared obstacles in some fields. Their repatriation
faces many difficulties, as long as flights are suspended and
borders get closed. The whole situation also hindered their
transportation, while more and more travel permits are needed,
according to each country. Not only crew changes, but also crew
recruitment was a hard to solve problem for the countries that
didn’t prohibited the second at all. This whole situation led
to the extension of seafarers’ service period. What’s also
worth saying is that lack of mobility makes it difficult for
the seafarers to get provisions.
According to a survey, which was conducted by
International Maritime Organization on December 2020, records
that ‘’ Due to COVID-related travel restrictions, approximately
400,000 seafarers are stranded on ships beyond the end of their
original contracts and unable to repatriate, thus a similar
number needs to join the ships in order to replace them.’’ More
and more people designate seafarers as key-workers, while 45
countries have agreed to this recognition and Greece is among
them. This update is the solution to this humanitarian crisis.
By this recognition, seafarers are allowed to travel unhindered
between the country of residence and ships as well as
repatriating at the end of their service. It is also said that
this particular designation provides them priority access to
safe vaccination.
By Tsortanidou Konstantina
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BENEFITS OF
BEING A sname MEMBER
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SNAME is an internationally recognized non-profit, professional
society of individual members serving the maritime and offshore
industries and their suppliers. For many, SNAME has been
absolutely essential to career development and success in the
industry. With more than 6,000 members around the world in 95
countries, SNAME is THE International Community for Maritime
and Ocean Professionals!
Student Membership
SNAME, formed in 1893 to serve naval architects and marine
engineers, has evolved over the years to serve the full spectrum
of the vessel life cycle, including:
Students - Educators/Researchers -
Engineers/Designers - Shipbuilders - Manufacturers - Operators -
Recyclers/Salvors. Together these make up the Faces of
SNAME. If you’re maritime,
you fit into this spectrum in at least one place, and this means
SNAME is the right place for you.
SNAME Members Only Features:
·
Internship
Opportunities (USD 10,000)
·
Discounts
to Events and Local Section Meetings (USD 400)
·
Involvement
in a Student Section (USD 500)
·
Access
to Senior Members & Mentoring (USD 1,717)
·
Access
to Additional Industry-Related Disciplines (USD 478)
·
Leadership
Opportunities – Local and International (USD 2,417)
·
Membership
is Recognition of Your Education/Experience/Competence (USD 150)
·
Prestige
Through Face of SNAME Recognition (USD 225)
·
Prestige
Through Awards and SNAME Fellow Status (1,302)
·
Forum
for Transcending Toward Significance (USD 833)
·
PE
Review Course (USD 10)
·
CEU/PDH
(USD 250)
·
Resume
Posting on Career Center (USD 188)
·
Access
to Posted Jobs on Career Center (USD 171)
·
20
Free Downloads per Year from Our Technical Library (USD 192)
·
Discounts
on Textbooks, Publications and Technical Papers (USD 133)
·
International
Community Access (USD 1,080)
·
SNAME
Alliance Partners Access and Discounts (USD 204)
·
Access
to SNAME Headquarters Staff (USD 278)
·
Weekly
Member Communication (USD 119)
·
Knowledge
Management (USD 140)
·
Networking
(USD 4,000)
All of the above is positive proof that SNAME membership
is a good business and career decision.
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