Vertical Shaft System

VERTICAL SHAFT SYSTEM

Introduction Tidal energy is interminable flow of energy. But it has not been still established that what can make the use of this energy very proficiently. Since the last decade it has been a point of interest for the scientists and engineers of building cost effective and energy efficient system for extraction of wave energy. But it isn’t still possible to make it easy and well-organized. So we here with very basic idea of vertical shaft are going to explore the idea of mining the energy of tides. Tidal motion can be easily connected or can be considered as the simple harmonic motion (SHM). The sinusoidal waves of water come up and get down in some approximate periodic motion. So it is easy to imagine the SHM of tides as up and down motion i.e. as vertical oscillatory motion. This up and down motion of water is the backbone of our project. We just use this to rotate a dynamo and produce electricity. Just imagine a piston rotating the wheel of the bicycle. Just after every ignition piston moves forward and after exhaust of waste gases it moves back and with help of the crank and shaft method the linear motion is thus converted to rotatory motion. In the similar way we came up with an innovative idea to explore it with linear to and fro motion of sea tides. But here we have some different arrangement instead of piston’s crank shaft we have replaced it with the clutch and chain arrangement. Further designing details are discussed throughout the project. We have first introduced some of commonly used sources of energy for electricity production and many of projects models prepared till now by various global scientists and engineers. We may not be par comparable to their high level models but we have something different to make it good. So we have created the model which is described in model description of this report. Objective of our project is to make use of that non-lasting energy of the nature’s powerful and continuous stream of energy coming from the sea, as water tides. We have tried to build a model cost efficient and use worthy and much dependable.

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Gestalt of Energy sources 1. WIND POWER: This energy is a result of difference in temperature over the globe, which leads to difference in pressure. The wind blows from the region of high pressure to that of a region of lower pressure. This flow can be used to rotate turbine using large wind blades. Thus wind energy can be harnessed for production of electricity.

2. SOLAR POWER: The Suns energy can be harnessed using photovoltaic cells and thermal energy converters. Thus heat energy from sun is directly converted to electrical energy. When photons hits silicon cells, they emit stream of electrons. These electrons flow as electric current

3. HYDRO POWER: Flow of water can be harnessed to generate electricity using waterwheels. Here we use turbines to rotate dynamo armature and thus use it to produce electricity. Sometimes tidal energy is also grouped under hydro power. But the Tidal sector had grown into a separate tropic and the discoveries have made it a vast subject.

4. PEIZO ELECTRIC POWER: It is somewhat tedious task, however very much useful in remote places where other process can’t work. Here some special materials called peizo materials are used. When they are compressed and released they emit energy of micro or millivolts used in delicate handling of microscopic level equipment such as Nano drugs.

5. THERMAL POWER: As we all know that heat can be used to produce electric power it has been a decades old practice to produce electricity using coal. Thermal power sector has its large impact in dry areas where dam construction and windmills are distinctly difficult to introduce. The places such as Deserts is an example.

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6. NUCLEAR ENERGY: Einstein and many others from their long study and invention showed to world that what can be done by just small amount of nuclear fuel. So after a systemized study of nuclear power, generators were so designed to produce heat using nuclear fuel and thus use it to pump dynamo system. And hence was the revolution conquered in the power sector. It is hazardous to world environmental health but it is inevitable.

7. TIDAL ENERGY: Most secured and continuous form of energy is tidal energy. Tides in the sea never stop and they can be used to produce electricity. It was the revolution that the tidal energy harnessing first came to human mind, in the past decade. And now it is one of the hottest topics in engineering and physical science to extract tidal energy.

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Tides Gravitational forces between the moon, the sun and the earth cause the rhythmic rising and lowering of ocean waters around the world that results in Tide Waves. The moon exerts more than twice as great a force on the tides as the sun due to its much closer position to the earth. As a result, the tide closely follows the moon during its rotation around the earth, creating diurnal tide and ebb cycles at any particular ocean surface. The amplitude or height of the tide wave is very small in the open ocean where it measures several centimeters in the center of the wave distributed over hundreds of kilometers. However, the tide can increase dramatically when it reaches continental shelves, bringing huge masses of water into narrow bays and river estuaries along a coastline. For instance, the tides in the Bay of Fundy in Canada are the greatest in the world, with amplitude between 16 and 17 meters near shore. High tides close to these figures can be observed at many other sites worldwide, such as the Bristol Channel in England, the Kimberly coast of Australia, and the Okhotsk Sea of Russia. List below contains ranges of amplitude for some locations with large tides. On most coasts tidal fluctuation consists of two floods and two ebbs, with a semidiurnal period of about 12 hours and 25 minutes. However, there are some coasts where tide are twice as long (diurnal tides) or are mixed, with a diurnal inequality, but are still diurnal or semidiurnal in period. The magnitude of tides changes during each lunar month. The highest tides, called spring tides, occur when the moon, earth and sun are positioned close to a straight line (moon syzygy). The lowest tides, called neap tides, occur when the earth, moon and Sun are at right angles to each other (moon quadrature). Isaac Newton formulated the phenomenon first as follows: ‘The Ocean must flow twice and ebb twice, each day, and the highest water occurs at the third hour after the approach of the luminaries to the meridian of the place’. The first tide tables with accurate prediction of tidal amplitudes were published by the British Admiralty in 1833. However, information about tide fluctuations was available long before that time from a fourteenth century British atlas, for example. Rising and receding tides along a shoreline area can be explained in the following way. A low height tide wave of hundreds of kilometers in diameter runs on the ocean surface under the moon, following its rotation Basaveshwar Science College, Bagalkot

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around the earth, until the wave hits a continental shore. The water mass moved by the moon’s gravitational pull fills narrow bays and river estuaries where it has no way to escape and spread over the ocean. This leads to interference of waves and accumulation of water inside these bays and estuaries, resulting in dramatic rises of the water level (tide cycle). The tide starts receding as the moon continues its travel further over the land, away from the ocean, reducing its gravitational influence on the ocean waters (ebb cycle).

List of Highest tides (tide ranges) of the global ocean: (Country, Site, Tide range (m)) Canada, Bay of Fundy, 16.2 England, Severn Estuary, 14.5 France, Port of Ganville, 14.7 France, La Rance, 13.5 Argentina, Puerto Rio Gallegos, 13.3 Russia, Bay of Mezen, (White Sea), 10.0 Russia, Penzhinskaya Guba, 13.4 The above explanation is rather schematic since only the moon’s gravitation has been taken into account as the major factor influencing tide fluctuations. Other factors, which affect the tide range are the sun’s pull, the centrifugal force resulting from the earth’s rotation and, in some cases, local resonance of the gulfs, bays or estuaries. Thus the tidal energy may vary for practical calculations than that of theoretical deviousness. So always practical and weather affected readings are taken to be in form to face the difficulties due to every change that occurs not only by moon but with every aspect.

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Energy of Tides The energy of the tide wave contains two components, namely, potential and kinetic. The potential energy is the work done in lifting the mass of water above the ocean surface. This energy can be calculated as: E=g ρ A ∫ z dz =0.5g ρ Ah2 Where E is the energy, g is acceleration of gravity, ρ is the seawater density, which equals its mass per unit volume, A is the sea area under consideration, z is a vertical coordinate of the ocean surface and h is the tide amplitude. Taking an average (g ρ) =10.15kN/m3 for seawater, one can obtain For a tide cycle per square meter of ocean surface: E=1.4h2 watt-hour or E=5.04h2, kilojoule. The kinetic energy T of the water mass m is its capacity to do work by virtue of its velocity V. It is defined by T=0.5mV2. The total tide energy equals the sum of its potential and kinetic energy components. Knowledge of the potential energy of the tide is important for designing conventional tidal power plants using water dams for creating artificial upstream water heads. Such power plants exploit the potential energy of vertical rise and fall of the water. Such an arrangement had been added in our project to overcome decades of unruly. In contrast, the kinetic energy of the tide has to be known in order to design floating or other types of tidal power plants which harness energy from tidal currents or horizontal water Sows induced by tides. They do not involve installation of water dams. Further every design created uses only kinetic energy. This vertical shaft method has been adjusted to absorb both forms of energy.

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Extracting Tidal Energy: Traditional Approach People used the phenomenon of tides and tidal currents long before the Christian era. The earliest navigators, for example, needed to know periodical tide fluctuations as well as where and when they could use or would be confronted with a strong tidal current. There are remnants of small tidal hydro mechanical installations built in the Middle Ages around the world for water pumping, water-mills and other applications. Some of these devices were exploited until recent times. For example, large tidal waterwheels were used for pumping sewage in Hamburg, Germany up to the nineteenth century. The city of London used huge tidal wheels, installed under London Bridge in 1580, for 250 years to supply fresh water to the city. However, the serious study and design of industrial-size tidal power plants for exploiting tidal energy only began in the twentieth century with the rapid growth of the electric industry. Electrification of all aspects of modern civilization has led to the development of various converters for transferring natural potential energy sources into electric power. Along with fossil fuel power systems and nuclear reactors, which create huge new environmental pollution problems, clean renewable energy sources have attracted scientists and engineers to exploit these resources for the production of electric power. Tidal energy, in particular, is one of the best available renewable energy sources. In contrast to other clean sources, such as wind, solar, geothermal etc., tidal energy can be predicted for centuries ahead from the point of view of time and magnitude. However, this energy source, like wind and solar energy is distributed over large areas, which presents a difficult problem for collecting it. Besides that, complex conventional tidal power installations, which include massive dams in the open ocean, can hardly compete economically with fossil fuel (thermal) power plants, which use cheap oil or coal, presently available in abundance. These thermal power plants are currently the principal component of world electric energy production. Nevertheless, the reserves of oil and coal are limited and rapidly dwindling. Besides, oil and coal cause enormous atmospheric pollution both from emission of greenhouse gases and from their impurities such as sulfur in the fuel. Nuclear power plants produce accumulating nuclear wastes that degrade very slowly, creating hazardous problems for future generations.

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Tidal energy is clean and not depleting. These features make it an important energy source for global power production in the near future. To achieve this goal, the tidal energy industry has to develop a new generation of efficient, low cost and environmentally friendly apparatus for power extraction from free or ultra-low head water Sow. Four large-scale tidal power plants currently exist. All of them were constructed after World War II. They are the La Rance Plant (France, 1967), the Kislaya Guba Plant (Russia, 1968), the Annapolis Plant (Canada, 1984), and the Jiangxia Plant (China, 1985).

Aerial view of the La Rance Tidal Power Plant (Source: Electricite H de France). All existing tidal power plants use the same design that is accepted for construction of conventional river hydropower stations. The three principal structural and mechanical elements of this design are: a water dam across the Sow, which creates an artificial water basin and builds up a water head for operation of hydraulic turbines; a number of turbines coupled with electric generators installed at the lowest point of the dam and hydraulic Basaveshwar Science College, Bagalkot

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gates in the dam to control the water Sow in and out of the water basin behind the dam. Sluice locks are also used for navigation when necessary. The turbines convert the potential energy of the water mass accumulated on either side of the dam into electric energy during the tide. The tidal power plant can be designed for operation either by double or single action. Double action means that the turbines working both water Sows, i.e. during the tide when the water Sows through the turbines, filling the basin, and then, during the ebb, when the water Sows back into the ocean draining the basin. In single action systems, the turbines work only during the ebb cycle. In this case, the water gates are kept open during the tide, allowing the water to fill the basin. Then the gates close, developing the water head, and turbines start operating in the water Sow from the basin back into the ocean during the ebb. Advantages of the double-action method are that it closely models the natural phenomenon of the tide, has least effect on the environment and, in some cases has higher power efficiency. However, this method requires more complicated and expensive reversible turbines and electrical equipment. The single action method is simpler, and requires less expensive turbines. The negative aspects of the single action method are its greater potential for harm to the environment by developing a higher water head and causing accumulation of sediments in the basin. Nevertheless, both methods have been used in practice. For example, the La Rance and the Kislaya Guba tidal power plants operate under the double-action scheme, whereas the Annapolis plant uses a single-action method.

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Recent trends As mentioned earlier, all existing tidal power plants have been built using the conventional design developed for river power stations with water dams as their principal component. This traditional river scheme has a poor ecological reputation because the dams block fish migration, destroying their population, and damage the environment by Sodding and swamping adjacent lands. Flooding is not an issue for tidal power stations because the water level in the basin cannot be higher than the natural tide. However, blocking migration of fish and other ocean inhabitants by dams may represent a serious environmental problem. In addition, even the highest average global tides, such as in the Bay of Fundy, are small compared with the water heads used in conventional river power plants where they are measured in tens or even hundreds of meters. The relatively low water head in tidal power plants creates a difficult technical problem for designers. The act is that the very efficient, mostly propeller type hydraulic turbines developed for high river dams are inefficient, complicated and very expensive for low-head tidal power application. These environmental and economic factors have forced scientists and engineers to look for a new approach to exploitation of tidal energy that does not require massive ocean dams and the creation of high water heads. The key component of such an approach is using new unconventional turbines, which can efficiently extract the kinetic energy from a free unconstrained tidal current without any dams. Many models explored below help us to understand the technique behind the tidal energy extraction. Also the models are studied to know their black sides and thus to eliminate those. We know that sufficient advancement has been established in other forms of energy source but tidal energy is an exception. Besides of its age the non-steady ness has made scientist to work long with vain and succeed far apart. Various models are already at work but are not working satisfactorily. So research is the need of an hour.

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Preceding Models Helical turbine (created in around 1994): This cross-Sow turbine was developed in 1994. The turbine consists of one or more long helical blades that run along a cylindrical surface like a screw thread, having a so-called airfoil or ‘airplane wing’ profile. The blades provide a reaction thrust that can rotate the turbine faster than the water Sow itself. The turbine shaft (axis of rotation) must be perpendicular to the water current, and the turbine can be positioned either horizontally or vertically. Due to its axial symmetry, the turbine always develops unidirectional rotation, even in reversible tidal currents. This is a very important advantage, which simplifies design and allows exploitation of the double-action tidal power plants. A pictorial view of a floating tidal power plant with a number of vertically aligned triple-helix turbines is shown in Figure.

Figure of Helical Turbine

Tidal fence Tidal fences look like giant turnstiles. They can reach across channels between small islands or across straits between the mainland and an island. The turnstiles spin via tidal currents typical of coastal waters. Some of these currents run at 5–8 knots (5.6–9 miles per hour) and generate as much energy as winds of much higher velocity. Because seawater has a much higher density than air, ocean currents carry significantly more energy than air currents (wind). Tidal fences are composed of Figure of unit of Tidal fence individual, vertical axis turbines which are mounted within the fence structure, known as a caisson, and they can be thought of as giant turn styles which completely block a channel, forcing all of the water through them as shown in figure.

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Tidal turbines Tidal turbines look like wind turbines. They are arrayed underwater in rows, as in some wind farms. The turbines function best where coastal currents run at between 3.6 and 4.9 knots (4 and 5.5 mph). In currents of that speed, a 15-meter (49.2-feet) diameter tidal turbine can generate as much energy as a 60-meter (197-feet) diameter wind turbine. Ideal locations for tidal turbine farms are close to shore in water depths of 20–30 meters (65.5–98.5 feet). There are different types of turbines that are available for use in a tidal barrage.

Bulb turbine: A bulb turbine is one in which water flows around the turbine. If maintenance is required then the water must be stopped which causes a problem and is time consuming with possible loss of generation. The La Rance tidal plant near St Malo on the Brittany coast in France uses a bulb turbine. Bulb hanger Bulb hanger

Turbine blade

nger Water flow

Bulb hanger Bulb hanger

Bulb hanger

Bulb casing

Distributor Steady Plinth

Rim turbine: When rim turbines are used, the generator is mounted at right angles to the to the turbine blades, making access easier. But this type of turbine is not suitable for pumping and it is difficult to regulate its performance. One example is the Starflower turbine used at Annapolis Royal in Nova Scotia.

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Generator

Both the above turbines make use of kinetic energy of wave but never can utilize the potential energy of the wave when it’s up.

Tubular turbine: Generator Gear Box Runne r

Tubular turbines have been proposed for the UK’s most promising site, The Severn Estuary, the blades of this turbine are connected to a long shaft and are orientated at an angle so that the generator is sitting on top of the barrage. The environmental and ecological effects of tidal barrages have halted any progress with this technology and there are only a few commercially operating plants in the world. The all above described turbines work similar to wind turbine technology itself. Also they distinctly disturb water life and distract their environment due to the noise they produce. Also they are large in size and difficult to produce. It was this adverse effect we saw in the most of the devices formerly formed and hence we decided to go with most of our thing above the water. We were in need a model which is enriched with eco friendliness most particularly ocean friendly generators.

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Our Model: Vertical shaft piston. We were thinking of doing something useful which can be not just a imaginative idea but we wanted it to really carve out. We started with a topic tidal energy. We studied various models and the realized that we can work there. So we thought of various models and surfed internet for already discovered models. After studying them it was then when idea of motor vehicle piston, a to and fro linear SHM, sprouted. We then started to think how to install it into our model. It was tedious task to convert a vehicle piston design to light but strong and steady model which can work for longer linear gesture. Our model has been carefully carved as to give many facilities such as portability, resizing gears and many more. Only that we were unable to add was the height adjustment the third dimension. What we have chosen is somewhat novel to the field of electrical energy production. But may be a far success if properly propelled in various facets. We have fabricated to our level best and the diagram is shown in the next page. We have mention about material usage and design process. Now we shall highlight which paraphernalia we have used in our model. We just used bi-cycle parts (crank wheel, chain, Back wheel with clutch), bearings, dynamo, a four legged table base and wooden planks. As you can see in the model that a rim of back wheel of the cycle with a clutch arrangement is fixed to the planks. A crank wheel is fixed at equal height as that of clutch, so as to keep chain straight. Further the chain is attached to elastic band fixed on plank so that chain rounds up the clutch wheel. The other end of chain is fixed with plank, which works as our piston. To keep the plank movement stable even when the turbulent water hits, it has been fixed between sliders. The plank motion is restricted to 6cm by slide stops. All above arrangement is placed over a table base. A dynamo is placed in just contact with the rim. As the plank, piston moves to and fro this motion is then converted to rotatory motion by clutch arrangement this is then directly transferred in 1:1 ratio to rim. This rotation of rim rotates geared up dynamo. The dynamo is connected to a 3V LED which glows for the frequency of dynamo wheel of about 6Hz. This part is further discussed in the efficiency calculation part of this report. Basaveshwar Science College, Bagalkot

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Now we have come to a point where we are going to calculate the force or impulse that is going to act on the piston board of our ideal. We first have to overlook on the topics wave energy and wave spectra.

Wave Energy Wave energy E in Joules per square meter is related to the variance of sea-surface displacement ζ by:

Wave amplitude (m)

E=ρwg< ζ > Where ρw is water density, g is gravity, and the brackets denote a time or space average. A graph is shown below:

Time(s)

A short record of wave amplitude measured by a wave buoy in the North Atlantic. Wave energy do mean that the total energy stored in wave for a given instant of time and actually it is sum of both potential and kinetic forms of energy stored in the wave/tide for that particular instant. The sum here we mean not algebraic rather it is a tensor sum of both potential and kinetic energies.

Tensor: A three dimensional quantity.

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Significant Wave Height What do we mean by wave height? If we look at a wind driven sea, we see waves of various heights. Some are much larger than most, others are much smaller. A practical definition that is often used is the height of the highest 1/3 of the waves, H1/3. The height is computed as follows: measure wave height for a few minutes, pick out say 120 wave crests and record their heights. Pick the 40 largest waves and calculate the average height of the 40 values. This is H1/3 for the wave record. The concept of significant wave height was developed during the World War II as part of a project to forecast ocean wave heights and periods. Wiegel (1964: p. 198) reports that work at the Scripps Institution of Oceanography showed ... Wave height estimated by observers corresponds to the average of the highest 20 to 40 per cent of waves ... Originally, the term significant wave height was attached to the average of these observations, the highest 30 per cent of the waves, but has evolved to become the average of the highest one-third of the waves, (designated HS or H1/3)…. More recently, significant wave height is calculated from measured wave displacement. If the sea contains a narrow range of wave frequencies, H1/3 is related to the standard deviation of sea-surface displacement (NAS, 1963: 22; Hoffman and Karst, 1975). H1/3 =41/2 Where 1/2 is the standard deviation of surface displacement. This relationship is much more useful, and it is now the accepted way to calculate wave height from wave measurements. Also wind speed can be taken as the parameter for the wave height. The winds sweep decides a major part in this aspect. And the relation goes directly proportional. And on that here we have a sample data derived from calculations by Pierson-Markowitz during their study of wave spectrum. The graph of a typical wave height versus wind speed is shown in figure below. By figure it is clear that for linear increase in wind speed height of wave increase very smoothly in curve form below wind speed.

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Period (s)

Significant Wave Hei (m)

Wind Speed (m/s)

Wave Momentum Momentum in general is the product of velocity and mass, which describes the quantity that a body can impart to another with which it collides. But wave momentum is somewhat different and complex to understand hence it is clearly explained below The concept of wave momentum has caused considerable confusion (McIntyre, 1981). In general, waves do not have momentum, a mass flux, but they do have a momentum flux. This is true for waves on the sea surface. Ursell (1950) showed that ocean swell on a rotating Earth has no mass transport. His proof seems to contradict the usual textbook discussions of steep, non-linear waves such as Stokes waves. Water particles in a Stokes wave move along paths that are nearly circular, but the paths fail to close, and the particles move slowly in the direction of wave propagation. This is a mass transport, and the phenomena is called Stokes drift. But the forward transport near the surface is balanced by an equal transport in the opposite direction at depth, and there is no net mass flux.

Solitary Waves Solitary waves are another class of non-linear waves, and they have very interesting properties. They propagate without change of shape, and two solutions can cross without interaction. The first solution was discovered by John Scott Russell (1808–1882), who followed a solitary wave generated by a boat in Edinburgh’s Union Canal in 1834.

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s

(

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Scott witnessed such a wave while watching a boat being drawn along the Union Canal by a pair of horses. When the boat stopped, he noticed that water around the vessel surged ahead in the form of a single wave, whose height and speed remained virtually unchanged. Russell pursued the wave on horseback for more than a mile before returning home to reconstruct the event in an experimental tank in his garden.—Nature 376, 3 August 1995: 37 The properties of a solitary waves result from an exact balance between dispersion which tends to spread the solitary wave into a train of waves, and nonlinear effects which tend to shorten and steepen the wave. The type of solitary wave in shallow water seen by Russell, has the form: ζ = a sech2 [(3a/4d3)1/2(x − ct)] Which propagates at a speed: c = c0

(1+

a 2d

)

You might think that all shallow-water waves are solutions because they are non-dispersive, and hence they ought to propagate without change in shape. Unfortunately, this is not true if the waves have finite amplitude. The velocity of the wave depends on depth. If the wave consists of a single hump, then the water at the crest travels faster than water in the trough, and the wave steepens as it moves forward. Eventually, the wave becomes very steep and breaks. At this point it is called a bore. In some river mouths, the incoming tide is so high and the estuary so long and shallow that the tidal wave entering the estuary eventually steepens and breaks producing a bore that runs up the river. This happens in the Amazon in South America, the Severn in Europe, and the Tsientang in China.

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Waves and the Concept of a Wave Spectrum If we look out to sea, we notice that waves on the sea surface are not simple sinusoids. The surface appears to be composed of random waves of various lengths and periods. How can we describe this surface? The simple answer is, Not very easily. We can however, with some simplifications, come close to describing the surface. The simplifications lead to the concept of the spectrum of ocean waves. The spectrum gives the distribution of wave energy among different wave frequencies of wave lengths on the sea surface. The concept of a spectrum is based on work by Joseph Fourier (17681830), who showed that almost any function ζ(t) (or ζ(x)ifyou like), can be represented over the interval −T/2 ≤ t ≤ T/2asthe sum of an infinite series of sine and cosine functions.

Sampling the Sea Surface The most important and tedious job of any project is to find whether the prototype can with stand various other side effects and can tolerate other difficulties that may cause damage. So testing a sample has been a part of all projects. Here we are taking into the world of tidal energy the test of sea for a sample. Calculating the Fourier series that represents the sea surface is perhaps impossible. It requires that we measure the height of the sea surface ζ(x, y, t) everywhere in an area perhaps ten kilometers on a side for perhaps an hour. So, let’s simplify. Suppose we install a wave staff somewhere in the ocean and record the height of the sea surface as a function of time ζ(t). We would obtain a record like that in figure 16.2. All waves on the sea surface will be measured, but we will know nothing about the direction of the waves. This is a much more practical measurement, and it will give the frequency spectrum of the waves on the sea surface. Working with a trace of wave height on say a piece of paper is difficult, so let’s digitize the output of the wave staff to obtain ζj ≡ ζ(tj), jt≡ j∆ j =0, 1, 2, ···,N− 1 Where ∆ is the time interval between the samples, and N is the total number of samples. The length T of the record is T = N ∆. Figure shows the first 20 seconds of wave height from figure 4 digitized at intervals of ∆ Basaveshwar Science College, Bagalkot

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= 0.32 s.

Figure representing the first 20 seconds of digitized data for ∆ = 0.32 s.

Now after the discussion of all associated issues let’s just estimate efficiency of our assembly. So let’s first analyze and practically compute the efficiency. Considering the prototype, gear up system take a major role and hence first let’s calculate its numerical traits and statics.

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Analysis of the Prototype Clutch wheel radius, r=3.5cm=0.035m Circumference of clutch wheel=2x3.142x r =2x3.142 x 0.035 =0.21994m Chain that rolls over the clutch wheel= the difference in length of elastic band expanded and compressed (