Design Study of Optimal Material and Energy Usage for Transport Thesis
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Design Study of Optimal Material and Energy Usage for Transport Thesis presented for the degree of Ph D in the 'University of London and for the Diploma of Membership of.Imperial College of Science and Technology by John West, B Sc, C Eng, FRINA, FI Mar E January 1980 CONTENTS 1. Preliminaries 2. Survey of Recent Trends in all Forms of Transport 3. A Concept of 'in depth Design of a Ship' 4. The Design of an Aerostatic Vehicle for Use in Low Air Corridors (Skyship) 5. The Hybrid Car 6. Conclusions 7. Suggestions for Further Work 8. References 1 PRELIMINARIES 2 1 PRELIMINARIES 1.1 SYNOPSIS AND OBJECTIVES There are numerous and varied definitions of "Design" but few of them adequately portray its true meaning when considering systems or complex structures. Design begins with an "in-depth" relationship with the subject and its environs. It requires experience directly or closely associ- ated with the subject. It demands clarity of thought in dealing with the varied claims which must be chronicled in order of importance, before the designer can begin to search for a solution. It also requires an innovatory skill so that solutions can be naturally born. Finally it demands our economic perception so that as the project is developed it is viable from all points of view. The present world plight adds a further dimension to design. Shortages of space, material and engery are coupled with increasing population and a need to improve the standard of living of the Third World. The projects covered in this thesis are at the other end of the spectrum from the supersonic 'Concorde' and the high performance motor car. It was this background which caused the rejection of a *project which had been studied extensively by the writer, namely the submersible or semi-submersible cargo ship. This was because, although the performance of such vessels improves with speed, there is no commercial case for fast ships. 'Skyship' and the 'hybrid' car, both of which are described later in this thesis, require minimum fuel, are designed for their environment, use simple forms of construction are create local industry. Finally the satisfactory result of good design is its translation into acceptable hardware. For both Skyahip and the hybrid car, the procedure for realising this goal is outlined in what follows. 1.2 DEDICATION This work is dedicated to the cause of strengthening the links between the academics and the practitioners. The practical application of the knowledge accumulated in Universities and research establishments can only bring benefit to the developing world. 5 1.3 ACKNOWLEDGEMENTS For Canberra, the small design team of- the Peninsular & Oriental Steam Navigation Company, Yarrow Admiralty Research Department, both hydrodynamics and aerodynamics departments of the National Physical Laboratory and Rupert Cameron, Naval Architect of the shipbuilders Harland and Woolf all shared in its development. For Skyship, wind tunnel tests and useful discussions have taken place at British Hovercraft and Cranfield Institute of Science and Technology. Considerable advice has also been given by John Wood of Airships Development Ltd., and critical appreciation of the earlier studies by Patscentre International. For the hybrid car, Val Pender of Nova Cars, Jeffrey Lee of Lee-Dickens and the Department of Electrical Engineering at Warwick University have all made substantial contributions. General advice on energy saving in Transport has been given by John Allen of Hawker Siddely Aviation and Professor John M Alexander as Supervisor has provided considerable assistance and guidance as a result of discussions and debate. For typing and compiling the Thesis the work of Trisha Cocking and Juliet Rigby is acknowledged and appreciated. 2 SURVEY OF RECENT TRENDS IN ALL FORMS OF TRANSPORT 7 2.1 INTRODUCTION The evolution of world transport over the last 150 years has been marked by extensive innovation in specific areas and there seems little abatement to the flow of novel ideas or the re-emergence of old concepts. Total traffic volume in the world continues to increase at a substantial rate and there is plenty of scope for new solutions, particularly in developing countries. However, not all novelties succeed - in fact there are far more failed ideas than actual successful systems. At the present time the interplay between transport novelties and new opportunities on the one hand and lack of resources and indecision on the other, is probably as complex as at any time in history.. Old successes and the potential of new ideas all rely upon accurate definition of fundamental requirements of transport systems. It is essential to list major criteria for choice between old and new alternatives and attempt to identify some of the more promising new systems expected to be developed in the next two or three decades. Responding to changes in availability of energy will be a major factor but there are several opportunities for novelty, provided the very special circumstances needed for their introduction can be successfully arranged. 2.2 INVENTION AND EXPLOITATION Next to housing and food, transport must be mankind's major requirement that makes demands on his ingenuity, finance and resources. Transport, whether it be horse chariot or Jumbo jet, has had remarkable effects on civilisation and large changes of liftstyle, culture and opportunity follow the introduction of new transport means such as the steam ship, railway and motor car. The place of the inventor is crucial in the process of novelty and it is sterile to argue whether the inventor or the need is the primary motive. What is clear is that for any successful new transport system there are many more allegedly superior alternatives that, in spite of clear advantages and consider- able effort, fail to dislodge the established method. To the economist the introduction of a major new transport system can be regarded from the viewpoint of penetration of a market. The work of Marchetti and Nakicenovic (Reference 1) in developing logistic substitution models illustrates this market feature very well (Figure1.) Figures 2.& 3.(Reference 2) shows how US and UK intercity car traffic grew at the expense of rail and how it will possibly itself later be penetrated by the growth of air travel. The growth 10 F 1 - F F 102 0.99 101 0.90 COAL WOO 10° 0.50 0.10 OIL,. I' NATURAL GA & NUCLEAR 10-2 0.01 1850 1900 1950 2000 2050 YEAR g. 1. WORLD - PRIMARY ENERGY SUBSTITUTION (SHORT DATA) 11 F F 1 - F 0.99 102 101 0.90 .\` / \ CAR / ,\ / AIR 0.50 10° \ . / / \ / \,` / / 0.10 \ i TRA:N / \ -2 10 0 01 1900 1950 2000 2050 2100 YEAR Fig.2. INTERCITY PASSENGER KM IN U.S. 12 F 1 - F 1.0 ROAD 1.0 .10 _._...WATER_ _ .01 4 1960 1962 1964 1966 1968 1970 1972 Fig. 3 BRITISH TRANSPORT `;ODUL SPLIT 13 of transatlantic air travel, leading to the demise of the ocean-going passenger liner is shown in Figure 4, which also illustrates the marked acceleration of the process by the coming of the jet engine. Although the logistic substitution model - has proved to be a powerful tool in quantifying historical evidence and is also being used for prediction of future trends it is too coarse to discriminate between competing embryonic systems. Only when the market penetration has reached 1% does the logistic substitution model become a reliable predictor. This is remarkable enough, but the major decision to embark on the quite substantial launching costs of a new system would have to be committed long before even 1% market penetration was achieved. Hence this otherwise powerful technique could not be used to decide between say the Stirling Cycle engine, the electric battery or a hybrid of the two as a major replacement system for the present day simple motor car with its internal combustion engine running on petrol. Some other criteria for select- ing new opportunities are clearly needed. Various analyses of alternative means of transport means covering wide ranging distances and trip times have been used in attempts to 14 F F 1 — F 102 c .99 JET i01 .90 i . PISTON i . 10° / J .50 i 11 / / / . / .10 10-2 .01 1950 1960 1970 1980 YEAR Fig. 4. AIR v SHIP NORTH ATLANTIC PASSENGERS 15 identify missing systems requiring development. Gabrielli and Von Karman (Reference 3) plotted the characteristics of all transport vehicles on a basis of specific power indicating a universal practical limit to efficiency for a given speed. The hovercraft filled an obvious need shown by this relationship. Elle (Reference 4) established a simple relationship between travel time and distance, viz t = 0.1 x X0.65 (Figure 5) and Bouladon (Reference 5) restated this in a way which indicated two significant transport gaps. These were at speeds and distances lying between walking and the motor car, typically encountered in a town or city, and between the railway train and the long distance airliner over a few hundred kilometres. It is worth studying the progress in attaining these two deficiencies.. The first is essentially the travelator or horizontal escalator, much loved by the science fiction writer. The requirement is for a speed of about 30 mph over intra-urban distances of a few miles. Bouladon developed this concept further than any previous system (Figure 6). His "Integrator" ingeniously arranged an accelerating stage which provided a smooth transition from walking on the travel- ator to its steady cruising speed. This was proved by actual demonstrator equipment. Another essential innovation overcame the problem of capital 16 10.0 .',..RAIL . PRIVATE CAR BICYCLE BUS ' WALKING ''' .•',. ON 0.1 DURATI 0.01 0.1 1.0 10.0 100 1000 X (DISTANCE IN KM) t = 0.10 x o.65 Fig.