22
23
R
oel Marissen, a senior scientist with DSM
Dyneema: ‘Dyneema
®
is the strongest
fibre in the world and, at the same time,
it is very light and flexible. So it is widely
used, for example in cables in the offshore
industry but also in safety gloves and
bullet-proof vests. A few years ago, someone came
up with the idea of using it in a barrier that could be
deployed automatically to protect nuclear power
plants or cities from tsunamis.’
‘How does it work? Behind the beach, along the coast,
you dig out a channel over the required distance. That
may be a few kilometres. You position the barrier in
the channel, anchoring it firmly in the subsurface.
When a tsunami arrives, the force of the water makes
the barrier unfold and a float brings it upright. The
float is anchored with cables. The result is a wall
that can withstand up to 20 metres of water.’
‘The question is, of course, whether the theory
will work in practice. Would the barrier unfold
automatically? Would it be strong enough for a
tsunami? Would the float idea work? We went to
Deltares to get answers. They know about water
forces there, and about how tsunamis behave, and
they have the experimental facilities where designs
can be tested to scale. That was exactly what
we needed.’
‘The design was first modelled in the computer and
then thoroughly tested. And it works. It stays upright
in all conditions, even if the tsunami exceeds the
design level. Even so, a lot of practical questions
remain. We hope we can now find a company or a
government who wants to work on the answers and
on the further development of the Tsunami Barrier.’
Alliance between Deltares and industry produces innovative
techniques and creates newmarket opportunities for business.
TSUNAMI BARRIER
For more information:
Would you like to see how the Tsunami Barrier works? Go to
or scan the code.
Designs tested to scale in the Deltares research facilities
T
he population in Saudi Arabia is growing fast
and demand for drinking water and electricity is
following. However, like other places in the Middle
East, Saudi Arabia lacks natural supplies of fresh water
and the country relies on the desalinisation of seawater,
a process requiring evenmore electricity. As a result,
desalinisation plants are often built in combination with
power stations, for example in Yanbu, near the Red Sea.
The Yanbu 3 station will produce 550,000m
3
of fresh water
a day, as well as 2400 MWof electricity. That requires a
lot of seawater: 290m
3
a second, 2.5millionm
3
every day.
A stable flow of water to the pumps taking the water to
the station is crucial. A sub-optimal flowmeans that the
pumps use more energy than necessary and theymay
start to vibrate, causing damage so that expensive pumps
have to be replaced sooner. There is also an increased risk
of a pump malfunction and a shutdown of the plant. The
Korean contractor Doosan asked Deltares to test the flow
to the pumps in Yanbu 3 and to optimise the design of the
pump compartments.
For more information:
FLOW TO PUMPING STATION OPTIMISED
PHOTO: SAM RENTMEESTER, RETOUCHING BY MATERS & HERMSEN
Test water discharge.
The water is pumped back
into the container for
recycling through a cellar.
The pump
compartments
with the pumps.
In reality, there are
29 pumps with
3 different functions:
for cooling water,
desalination and
the cleaning the
exhaust gases from
the power plant.
After the water
has been filtered,
it is sent to the
pumps in the
distribution zone.
Wooden
walkway for the
researchers.
The water is filtered in drums. Waste is
removed here to stop the pumps getting
clogged. In reality, the drums have a diameter
of 11 metres.
Ballast keeps the wooden model
in place, preventing it from
floating. The model was built
to a scale of 1:12.
Water from
the IOS Basin,
in reality the
Red Sea.
Researcher
Femke Verhaart
injects ink into
the water to
show the flow
and make it clear
how the water
flows to the
pumps.
If there is a tsunami, the barrier
unfolds and the land (to the left
of the blue barrier) is kept dry.
KNOWLEDGE
IN OPERATION
DELTARES , SEPTEMBER 2014
