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There is considerable energy available from ocean currents. The velocity of these is generally low and it varies with location, the seasons, and with depth from the ocean surface. It is possible to use this energy for power generation and an analysis is presented reviewing various types of water turbines, including Water Wheels, Kaplan Turbines, Propeller Turbines and Vertical Axis Machines. The analysis evaluates the effects of velocity gradients and the machines best suited for this application. Due to the low energy flux, the machinery will get relatively large and is of slow speed. However, since substantial amounts of energy are available, such water turbines may become of interest in specific locations where such units can be built close to the source of energy demand.

The oceans and their environment have long been envisioned as renewable sources of energy. It is the purpose of this paper to assess the feasibility of drawing on the sea for power and to determine the extent to which the oceans are likely to serve future energy needs. A review is made of recent U. S. funding levels for the research and development of renewable energy sources during the fiscal years 1971–1975, and a study is made of the technical and environmertal acceptability status of tidal, wind, and sea thermal power generation systems. The estimated costs of these environmental power sources are compared with the prevailing power costs for nuclear and coal plants. On the basis of these comparisons, recommendations are made for a program of research and development culminating in the construction of prototype plants for wind and sea thermal power plants. Tidal power generation is found to be technically feasible but economically uninviting at present.

Many unique advantages have stemmed from the use of aircraft-type gas turbine power plants in selected marine propulsion applications; and, as expected, special problems have arisen because of the marine environment, primarily in the areas of parts integrity resulting from cold and hot corrosion and performance deterioration due to compressor fouling. Sulfur in the fuel, together with sea salt in the fuel and combustion air, creates major problems. Programs directed to reduce the detrimental effects, and the results attained are described.

Considerable progress has been made in the understanding of the concepts underlying the exploitation of tidal energy during the last 20 years; this progress has culminated in the actual construction of a tidal plant at the mouth of the Rance River near St. Malo, France. Since the Bay of Fundy is one of the largest reservoirs of tidal energy in the world, the theory of exploitation of tidal energy has been reviewed with a view to its application to the Bay of Fundy.The rate of change of the energy contained in an oscillating mass of water in a basin on a rotating earth can be written out using the equations of hydrodynamics. The concept of power transfer arises immediately, which enables one to follow the transit of power from one part of the basin to another. This makes it possible to establish a balance of the power present in the basin.Only the potential energy present in the tide can be profitably exploited, and it is obtained by enclosing part of the basin by a dam in which some turbines and pumps are imbedded, as well as some complementary sluices. The emptying and filling of the enclosed part of the basin through the turbines during the fall and rise of the sea leads to the production of energy. The upper bounds of the energy available in this way can be easily established and it can also be readily shown that the use of pumps increases the amount of energy available. The actual amount of energy drawn from the reservoir is limited by the smaller range of the tide inside the reservoir and the efficiency of the turbines. The timing and duration of the various operations involved in the operation of a tidal plant, pumping, generating power, opening or closing the sluices, waiting for a head to develop, can be studied quantitatively.For this purpose the type and number of fundamental operations are carefully studied and accurate definitions are given of them, permitting calculations on a number of possible sequences of operations up to 25 tidal periods. The number of possible sequences is very large and it is not possible to study all of these sequences individually.Under some circumstances a given sequence of operations for the actual times of starting and stopping the turbines, starting and stopping the pumps, opening and closing the sluices, waiting for a head, and the changes of level inside the reservoir can be calculated with the help of the calculus of variations. For instance, these quantities yield to systematic calculation if the plant is operated with the purpose of producing the maximum amount of energy. The calculus of variations, however, cannot help directly when other modes of operation are considered, such as operating the plant in such a way as to supply power only during peak demand.The response of the basin to the oscillating ocean will be altered after the construction of the reservoir needed for the operation of the tidal plant. This modification may be important when the plant draws considerable amounts of energy from the tide.With the help of the concepts developed it becomes an easy task to make a balance sheet for the tidal power present in the Bay of Fundy, restricting ourselves to M2, the main lunar semidiurnal constituent that is representative of average conditions. Many sites in the Bay of Fundy are found to be suitable for the generation of energy; some involve relatively simple engineering and yield modest amounts of energy such as the Digby site; others, such as the Minas Channel site, could yield very considerable amounts of energy but the engineering difficulties associated with their construction might prove prohibitive.

The main difficulty in harnessing solar energy is collecting it. The collection mechanism for solar sea power is the ocean. Solar energy, absorbed by the surface waters of tropical oceans, can be converted first into electric power by solar sea power plants, then convented by electrolysis into chemical energy, and transported by ship for distribution to heat homes, power transportation facilities, and form a basic ingredient in materials processing. The problems involved for a SSPP are insufficient temperature difference, corrosiveness of sea water, microbial fouling, plant anchoring, diluteness of solar energy in the ocean, and environmental effects. (MCW)

The marine power plant is usually designed only from the standpoint of its steady state. However, the accurate knowledge of the kinetics of the marine plant is quite necessary for its advanced design, especially for its automation.The kinetics of marine boilers and turbines have been investigated by some of the authors, but the transient characteristics of a whole plant have not been studied yet.In this paper, the authors show the experimental results of the plant-kinetics as to a big steam tanker, which were measured during the starting, power change, astern-and inertia-tests. The test results are also analized with an analog computer. And it is confirmed that the marine steam plant can be simulated with a simple mathematical model.

It is emphasized that reliability is by far the most important requirement in the control system of a marine power plant. The controls of the Pametrada 3,500-h.p. gas turbine, which is taken as a typical marine unit, are then discussed. The sprayers, control blocks, fuel system, transmission, reversing mechanism, and governors are described in turn, and the reasons are given why various features were adopted in preference to the possible alternatives. There is an account of test-bed experience concerning these items. Probable future developments in the field of controls are then considered, but these are found to depend mainly on the way in which the gas turbine itself is developed for marine purposes. The paper therefore concludes with a discussion of the type of gas turbine most likely to be installed in merchant vessels, and the means whereby it will be controlled.

The need for preventive maintenance of shipboard machinery has been well established. The necessity of insuring increased reliability of machinery and therefore availability of vessels can clearly be justified on economic grounds alone. Various methods to date rely on statistical means of predicting failure rates. This requires a large number of inspections of failures to develop confidence in the system. An alternative method to statistical analysis is one which is continuous in nature. This method of analysis is called the Deviation Concept. The application utilizes a portion of an on board computer for acquiring and analyzing equipment data. This data which is currently available aboard ship via instrumentation can be utilized effectively by the Deviation Concept.

Seasat-A is a new NASA satellite dedicated to oceanographic measurements of interest to a broad spectrum of the marine community. Its strong suit is an array of active and passive microwave instruments that give it the ability to view surface features on a day-night, near-all-weather basis. It will measure such features as wave heights, lengths, and directions; surface wind velocities; currents; temperatures; ice cover; and the marine geoid. Sensor capabilities and examples of their data output will be given, and the usefulness of these data for understanding the coastal marine environment will be discussed.

Publisher Summary This chapter discusses combustion in industrial gas turbines. Attempts have been made to operate industrial gas turbines on solid, liquid, and gaseous fuels of many different types, for application to the whole wide range of industrial and marine power production. The chapter discusses open, closed, semiclosed, and exhaust heated cycles. Long-life base load units have been derived by blending aero-techniques with steam turbine experience; short-life peak load units have been evolved by using aero-gas turbines as gas generators feeding power turbines. The fates of these many combinations of fuels, power plants, and applications have been determined by their technical feasibilities, practical operating characteristics, and overall running costs relative to the established prime movers. If the design of a single combustion chamber with a single atomizer and air register is attempted for an industrial unit of, say 4000 kW output, the resultant component may dominate the engine. In addition, to obtain an acceptable spray particle size would require a far higher fuel pressure than can be contemplated with confidence. Therefore, in large units, to obtain fine atomization, it is necessary to subdivide the fuel flow between a number of atomizers.

After presenting some of the attractive features and characteristics of the aircraft gas turbine for selected marine propulsion applications, this paper looks at those features of such engines that need improvement in order that they may become true marine power plants. Both cold and hot-corrosion problems are created by the marine atmosphere and the change from aircraft-type fuels to higher-sulfur-content marine fuels. Phases of a development program to produce the required features in the General Electric LM 1500 gas-turbine power plant are discussed.Copyright © 1965 by ASME

The general problem of the mixed-layer depth of the ocean's surface layers is discussed. Wind mixing and its contribution to mixed-layer depth at ocean station Papa during the year 1958 is evaluated. A model of mixing by wind- generated wave motion is tested along with two other models, and the results are discussed.

I REGRET that I am not able to accept the criticisms of Mr. C. Callaway on my notice of Prof. Ball's lecture. I have studied the effect of tidal and wind waves on many coasts through many years, and my observations do not warrant the statements he makes. Every schoolboy knows the distinction between waves of undulation and translation, and it is in no sense true that I have confused them. With waves of undulation such as occur in mid ocean we have nothing to do in this discussion, but it cannot be unknown to Mr. Callaway that all such waves when reaching a shore, become waves of translation, and more or less powerful denuding agents. If he will have the kindness to refer to my “Report on the Geology of Ohio,” vol. i. pp. 52, &c., he will find that I have done ample justice to the efficiency of wind waves as agents of geological change. The great tidal current rushing around the earth, with which he credits me, exists only in his Own imagination. I have suggested nothing of the kind, but the rapid ebb and flow over the shores of continents of tidal waves several hundred feet in height must necessarily act with great violence upon such shores, and I insist that such tidal waves as pictured by Prof. Ball would have left a very different record from that we find in our Palaeozoic rocks. Some of our American Silurian strata were deposited on shores that faced toward the east, where they had an unbroken stretch of several thousands of miles of ocean over which the tidal wave would come to them without obstruction, and there the maximum effect of such tides as Prof. Ball describes would be produced, but no traces of them are found.

In this paper the most suitable locations for erection of tidal power plants on the North Atlantic Coast are reviewed and classified in respect to the possible pool arrangement. The harnessing of the tides to produce power in various layouts is described. Due to the limited length of this paper, it was only possible to discuss and compare the power output from two proposed tidal power projects, Passamaquoddy Bay and Shepody Bay, and also to discuss some auxiliary power sources to supplement the varying output of tidal power. The tide producing forces and the effect of the coastline on the tide height is also briefly introduced.