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Diapositiva 1

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It's difficult to establish when man tried to dominate the power of the water. ... megawatts, but a few mammoth plants have capacities up to 10,000 megawatts and ... – PowerPoint PPT presentation

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Title: Diapositiva 1


1
Classes I.T.G. involved II A Matteo Grimaldi,
Ida Buoninconti,Giovanni DAuria, Luana Forte,
Mauro Pepe III A Anna DAndria, Anna De
Rosa II C Anna Cerrato, Alessia Cesaro III
C Roberta DEmma, Aniello Petrosino Daniele
Pisapia, Sabato Senatore V C Claudia Apuzzo,
Salvatore De Prisco Arturo Della Femina, Ida
Della Rocca Vincenzo Di Fiore, Annarita
Giordano Andrea Giordano Buono Umberto Nucaro,
Giuseppe Rodà Gaetano Stanzione, Domenico
Zuppetti
Technical School for Surveyors
Vanvitelli Water in Europe Analysis of the
three Q Quantità, Qualità and Quota
Teachers involved Leonardo Aloia, Rosa Rocco
Gianna Barrella, Michele Perone Stefano Proto,
Mario Napoli Luigi Giordano, Annamaria Salsano
2
Technical School for Surveyors Luigi
Vanvitelli Cava de Tirreni
and
S.M.S. Balzico S.M.S. Giovanni XXIII
Present
3
HISTORICAL EVOLUTION OF WATER SUPPLIES
From ancient civilizations
...to modern time
4
Egyptian, Greek, Etruscan and in particular Roman
Aqueducts
Medieval Aqueducts
Vanvitellis Carolingian Aqueduct
Hydropower plants
5
The dam of the Nile
Its difficult to establish when man tried to
dominate the power of the water. It seems likely
that it occurred in ancient times in the basin of
wide and important rivers such as the Nile, The
Euphrates and the Tigris. It is supposed that
Menes ordined the construction of some dams to
divert the course of the Nile and to erect the
town of Menfi there. If so, the first dam should
have been built in Egypt about three or four
thousand years before Christ.
6
Greek and Etruscan aqueducts
Other ruins of ancient waterpipes have been found
under a floor of Cnosso Palace, in Argo, in
Mycehae, in Tirinto, in Ithaca. Numerous are the
Greek aqueducts of different age and different
origin. Those ones which supplied the city of
Athens and the surrounding lowland up to the
Piraens formed a complex net of subterranean
pipes made of stones, covered with flat slabs, or
with tiles and provided with ventilating shafts.
We have no historical information about the
Etrurian aqueducts but since we know that the
Etrurians were skilled hydraulics, we should
think they knew the technique of subterranean
pipes dug in the rock. However, according to
archeological and written accounts given by
Frontino, Vetruvius and Pliny, the aqueduct as
elevated Monument is a Roman creation.
7
The Roman aqueducts
The aqueducts were invented and planned in Rome
in the V century a.c. because the water supply of
the city that drew water from the river Tiber or
from wells was not enough. Rome was getting the
bigger than most earlier towns had been so it got
too hard for the people in Rome to get drinking
and washing water. Because raw sewage was
draining into the rivers, people who drank river
water often got very sick or died. Local
governments decided to build long stone channels
to carry clean water from nearby hills to the
towns. These were called aqueducts from the latin
word for water (aqua) and the latin word for
channel (ducts) .The first aqueduct was the Aqua
Appia built in 312 a.c. and commissioned by the
homonym Consul Appio Claudio. Most Roman towns
had at least one aqueduct to bring fresh water,
and big cities like Rome had ten or more.
8
The structure
When we think of Roman aqueducts, we imagine high
and elegant structures and arcades supported by
pillars. These aqueducts were quite a challenge
to build. The engineering had to be just rigth in
other to get the water to run through the
channels and get to the city without stagnating
in the channel or coming too fast into the city.
They had to keep the slope the same all the time,
so sometimes the aqueducts had to run on high
arches, and other times along the ground in stone
channels or even under the ground in tunnels.
9
How Roman aqueducts worked
The aqueducts collected the water from various
natural springs situated very far from the town.
The water was chosen according to many factors
the position of its source, its purity, its
taste, its temperature and sometimes its supposed
curative properties. The water flew towards the
town thanks to the force of gravity. The aqueduct
worked as a continuous chute along the distance
which separated the springs from the outflow
point. In order to have this quality each
aqueduct was planned and designed in a way that
any single part of the course ran slightly
shorter than the previous one. That is why the
water had to be taken from the springs on the
hill.
10
The roman wit
The roman architects were skilful at doing this
activity for which they had sophisticated tools
at their disposal besides the common level they
used the chorobates, a kind of bench with
plumb-bobs on the sides to measure the
inclination of the terrain. The dioptra was a
different kind of level it was placed on the
ground and calibrated through the angle and
rotation of its upper part. It could calculate
the angle of descent of a part of the aqueduct,
pointing it with a system of rotating
viewfinders.
11
The course of the waters
Huge tanks along the course of many aqueducts
were used for removing any impurities from the
waters. Far from the urban area the course of the
waters flew underground. Vertical wells were dug
to Keep the way down, then the channel was cut
through the rock. The walls of the channel were
coated with a kind of cement called cocciopisto.
12
The Roman channels
The standard-size section of a Roman channel was
about 1 m. in width multiply by 2 m. in height,
but it could vary with the flow. The open
vertical wells were used for the maintenance of
the aqueduct. As water in Rome was rich in
calcium salt, an enormous number of sediments had
to be removed very often.
13
The respect for the aqueducts
To prevent damages and pollution along the
external course of the aqueduct, every 240 feet,
a big stone warned of the presence of an
underground channel and the respect for a safe
distance of 5 feet away from it. Since the
aqueducts were government property their damage
or pollution was severely punished. The same
accurred with the illegal use of the public water
mains.
14
Thespecus
The specus(channel) was coated with slabs to
protect water from the sunlight, from the mould,
from the leaves etc. the covering could be flat,
roundish or hipped.
15
The Roman Masonries
When the duct reached a wall or a gorge, a
possible solution was to build a bridge to cross
the leap and to reach the opposite side to a
slightly inferior height. Another way of
overcoming such natural formations was to cross
them with the inverted siphon, a technique
based on a simple physical principle.
Just before the leap, water was caught in a
cistern or tank from which a piping conducted it
towards the precipice because of the force of
gravity, after that it went up again to a second
tank thanks to the pressure produced along the
descent. A small viaduct was often built
downriver, to reduce the maximum height of the
leap.
16
The Arcades
Where the terrain was plane, famous series of
arcades were built. Some of them were about 30 m.
high. It was along these great structures that
the aqueducts arrived at Rome.
17
Medieval Aqueducts
Ancient techniques for water supply were used by
Architects in the construction of monasteries.
During the excavation of the Domenican Convent of
Zurich(1990) a clay piping in mortar casting came
to light. The water supply of the fortresses had
to work also in a state of sienge so pulley wells
and rainwater reservoirs were prevalent in this
period.
18
The medieval aqueduct Devils Arches
Devils Arches is the strange name that nowdays
the Salernitans give to the ancient aqueduct
erected in Salerno. According to the legend it
was built by a magician Pietro Barliario with the
help of the prince of darkness in one night
during the XIII century, saving people from the
death of thirst.
19
The aqueduct of Salerno has the same structure as
the Roman one. The particular beauty of this
construction convinced people that it had been a
diabolic work .As a matter of fact legend has it
that Pietro Barliario had made a pact with the
devil and the popular famous name devils
arches derives from that. The first arcade is
about 100 metres long , it raises up on piers
with square or rectangular bases that support 23
arches 3.10 metres long. The structure is made up
of limestone mixed to alluvial pebbles fragments
of brick, sandstone and travertine all binded by
a fine mortar. The length of the shaft is 16
metres long, the structure is similar to the
first shaft. Arch street , where the presence
of this aqueduct is stronger, has become one of
the busiest street in the city where many
buildings depreciate the beauty of this splendid
monument.
20
The Carolingian aqueduct and the bridges of the
Maddaloni Valley
It was necessary to build the Carolingian
aqueduct not only to feed the numerous fountains
and falls of the Royal Palace of Caserta but most
of all to guarantee the new Capitals water
supply and to provide the essential motivity for
the silk factories in the near San Leucio
The Vanvitellis masterpiece was commissioned by
the king Carlo III of the Bourbon dynasty, from
which the name Carolingian derives, to create
the extraordinary jet fountains in the gardens of
the Royal Palace of Caserta. It is one of the
most original work of the hydraulics architecture
in all times
21
The building of the Arcades as a Vanvitelli
loved calling them was started in March 1753 and
finished in November 1753. It was inaugurated on
7th May 1762.The complete work cost 600.000
ducats.
22
With its 529 m in lenght,55.80 m in height, three
lines of arcades of 19.28 and 43 for a total of
90 arcades, the great bridge links Mount Logano
(in the East) to Mount Garzano (in the West)
23
Turning waters mechanical energy into electricity
  • Since the time of ancient Egypt, people have used
    the energy in flowing water to operate machinery
    and grind grain and corn. However, hydropower had
    a greater influence on peoples lives during the
    20th century than at any other time in history
    and continues to produce 24 percent of the
    worlds electricity and supply more than 1
    billion people with power.

24
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25
Evolution of Hydropower
  • The first Hydroelectric power plant was built in
    1882 in Appleton, Wisconsin to provide 12.5
    kilowatts to light two paper mills and a
    home.Today hydropower plants generally range in
    size from several hundred kilowatts to several
    hundred megawatts, but a few mammoth plants have
    capacities up to 10,000 megawatts and supply
    electricity to millions of people.

26
How Hydropower Works
  • Hydropower is currently the largest and least
    expensive source of renewable electricity
    produced in the world. It captures the energy of
    falling water to generate electricity. The
    quantity of electricity generated is determined
    by the volume of water flow and the amount of
    head (the height from turbines in the power
    plant to the water surface) created by the dam.
    The greater the flow and head, the more
    electricity produced. A typical hydropower plant
    includes a dam, reservoir, penstocks (pipes), a
    powerhouse and an electrical power substation.
    The dam stores water and creates the head
    penstocks carry water from the reservoir to
    turbines inside the powerhouse the water rotates
    the turbines, which drive generators that produce
    electricity. The electricity is then transmitted
    to substation where transformers increase voltage
    to allow transmission to homes, businesses and
    factories.

27
Here are the basic components of a conventional
hydropower plant
  • DAM
  • PENSTOCK
  • TURBINE
  • GENERATORS
  • TRANSFORMER

28
Dam
Most hydropower plants rely on a dam that holds
back water, creating a large reservoir. Often,
this reservoir is used as a recreational lake,
such as Lake Roosevelt at the Grand Coulee Dam in
Washington State.
29
Penstock
A pipeline that leads to the turbine. Water
builds up pressure as it flows through this pipe.
30
Turbine
The water strikes and turns the large blades of a
turbine, which is attached to a generator above
it by way of a shaft. The most common type of
turbine for hydropower plants is the Francis
Turbine, which looks like a big disc with curved
blades. A turbine can weigh as much as 172 tons
and turn at a rate of 90 revolutions per minute
(rpm), according to the Foundation for Water
Energy Education (FWEE).
Francis type
Kaplan type
Pelton type
31
  • There are many types of turbines used for
    hydropower, and they are chosen based on their
    particular application and the height of standing
    waterreferred to as "head"available to drive
    them. The turning part of the turbine is called
    the runner. The most common turbines are as
    followsPelton TurbineA Pelton turbine has one
    or more jets of water impinging on the buckets of
    a runner that looks like a water wheel. The
    Pelton turbines are used for high-head sites (50
    feet to 6,000 feet) and can be as large as 200
    megawatts.Francis TurbineA Francis turbine has
    a runner with fixed vanes, usually nine or more.
    The water enters the turbine in a radial
    direction with respect to the shaft, and is
    discharged in an axial direction. Francis
    turbines will operate from 10 feet to 2,000 feet
    of head and can be as large as 800
    megawatts.Propeller TurbineA propeller has a
    runner with three to six fixed blades, like a
    boat propeller. The water passes through the
    runner and drives the blades. Propeller turbines
    can operate from 10 feet to 300 feet of head and
    can be as large as 100 megawatts. A Kaplan
    turbine is a type of propeller turbine in which
    the pitch of the blades can be changed to improve
    performance. Kaplan turbines can be as large as
    400 megawatts.

32
Generators
As the turbine blades turn, so do a series of
magnets inside the generator. Giant magnets
rotate past copper coils, producing alternating
current (AC) by moving electrons.
33
Transformer
The transformer inside the powerhouse takes the
AC and converts it to higher-voltage current.
34
The end
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