Design for Support in the Initial Design of Naval Combatants
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Design for Support in the Initial Design of Naval Combatants by Syavash Esbati A thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy (Naval Architecture and Marine Engineering) Department of Mechanical Engineering University College London 2018 1 To my family. 2 Declaration I, Syavash Esbati, declare that except where explicit reference is made to other sources, this thesis is the result of my own work. I confirm that this thesis has not been submitted for any other degree at University College London or any other institution. Print Name: Signature: 3 Abstract The decline of defence budgets coupled with the escalation of warship procurement costs have significantly contributed to fleet downsizing in most major western navies despite little reduction in overall commitments, resulting in extra capability and reliability required per ship. Moreover, the tendency of governments to focus on short- term strategies and expenditure has meant that those aspects of naval ship design that may be difficult to quantify, such as supportability, are often treated as secondary issues and allocated insufficient attention in Early Stage Design. To tackle this, innovation in both the design process and the development of individual ship designs is necessary, especially at the crucial early design stages. Novelty can be achieved thanks to major developments in computer technology and in adopting an architecturally-orientated approach to early stage ship design. The existing technical solutions aimed at addressing supportability largely depend on highly detailed ship design information, thus fail to enable rational supportability assessments in the Concept Phase. This research therefore aimed at addressing the lack of a quantitative supportability evaluation approach applicable to early stage naval ship design. Utilising Decision Analysis, Effectiveness Analysis, and Analytic Hierarchy Process, the proposed approach tackled the difficulty of quantifying certain aspects of supportability in initial ship design and provided a framework to address the issue of inconsistent and often conflicting preferences of decision makers. Since the ship’s supportability is considered to be significantly affected by its configuration, the proposed approach utilised the advantages of an architecturally-orientated early stage ship design approach and a new concept design tool developed at University College London. The new tool was used to develop concept level designs of a frigate-sized combatant and a number of variations of it, namely configurational rearrangement with enhancement of certain supportably features, and an alternative ship design style. The design cases were then used to demonstrate the proposed evaluation approach. The overall aim of proposing a quantitative supportability evaluation approach applicable to concept naval ship design was achieved, although several issues and limitations emerged during both the development as well as the implementation of the approach. Through identification of the research limitations, areas for future work aimed at improving the proposal have been proposed. 4 Impact Statement Despite the considerable number of issues that need further investigation, it is considered that this research has contributed to advancing the extent of what can be assessed in the early, formative stages of the design process of what Graham (US Navy Commander, quoted by Gates and Rusling (1982)) described as ‘the most the most complex, diverse and highly integrated of any engineering systems’ that is regularly manufactured today. The existing body of knowledge regarding the Early Stage Design of naval ships could benefit from this research in a number of ways, both outside and inside academia. This project was partly sponsored by BAE Systems; the largest defence and shipbuilding company in the UK and one of the world’s largest producers of complex warships. During three and half years of research work at UCL, regular project meetings with BAE Systems representatives helped gain valuable practical insights. Additionally, the ship designs developed as part of this research were based on the broad specifications of the Type 26 Global Combat Ship programme that recently entered construction at BAE Systems’ Govan and Scotstoun shipyards on the River Clyde in Glasgow, UK. It is hoped that the outcome of this research will support BAE Systems involvement with the UK MoD in better addressing the UK MoD’s stated intentions to give equal emphasis to through-life (support) issues as to initial (purchasing) affordability. By stating how Design for Support (DfS) can start to be addressed at the earliest design stages in complex naval vessels, this research will encourage BAE Systems to take such approaches as are demonstrated in this thesis into actual ship design programmes of the future. The insights generated could be used to justify further research into a number of areas, namely naval ship life cycle costing and application of the proposal in this thesis to those aspects of naval ship supportability that were not considered in this research and to a wider range of ship types. In addition, the feedback from this research on the application of academic concept ship design tools could help improve these softwares’ robustness and capability. 5 Acknowledgments Whilst I as sole author bear full responsibility for the research presented in this thesis, it would not have been possible without the support and encouragement of a number of individuals both from within the UCL community and beyond. First and foremost, I would like to express my gratitude to my supervisors; Prof. David Andrews, for giving me the opportunity to work in his research groups and his exemplary support and guidance throughout my PhD; and Dr. Rachel Pawling for her generous assistance, insightful comments, and the many casual, yet productive discussions. I would also like to acknowledge the help readily provided to me by the staff of the Naval Architecture and Marine Engineering Office and the wider UCL Department of Mechanical Engineering, in particular Dr. Alexander Piperakis and Dr. Nick Bradbeer. Funding for this project was provided by EPSRC (CASE studentship) and sponsorship by BAE Systems, for which I am grateful to both institutes. Special thanks go to BAE Systems representatives – Dr. Malcolm Robb; Dr. Richard Trumper; and Mr David Lewis, all of whom belong to the Research & Technology Group at BAE Systems Maritime Naval Ships – for the valuable practical insights gained during regular project meetings. Finally, I am especially grateful to my family for their infinite support, understanding, and continued encouragement throughout my PhD. 6 Design for Support in the Initial Design of Naval Combatants Table of Contents Table of Contents ___________________________________________________ 7 Table of Figures ____________________________________________________ 11 List of Tables ______________________________________________________ 18 Nomenclature______________________________________________________ 21 List of Symbols ____________________________________________________ 27 Chapter 1: Introduction ___________________________________________ 29 1.1 Preamble ______________________________________________ 29 1.2 Research Scope and Aim _________________________________ 31 1.3 Thesis Structure _________________________________________ 33 Chapter 2: A Review of the State of the Art in Design for Support for Naval Ships _________________________________________________ 35 2.1 Introduction ____________________________________________ 35 2.2 Naval Ship Design ______________________________________ 37 2.2.1 Background to the Process of Naval Ship Design and Procurement ___________________________________________________ 37 2.2.2 The Cost of Owning a Warship __________________________ 39 2.2.3 Introduction to Naval Ship Design ________________________ 47 2.2.4 Traditional Early Stage Naval Ship Design _________________ 51 2.2.5 Architectural Modelling in Early Stage Naval Ship Design _____ 54 2.2.6 The Design Building Block Approach _____________________ 57 2.3 Naval Ship Supportability _________________________________ 66 2.3.1 Introduction to Naval Ship Supportability __________________ 66 2.3.2 Architecturally Discernible Aspects of Naval Ship Through-Life Support _____________________________________________ 69 2.3.3 Technical Solutions Addressing the Architecturally Discernible Aspects of Naval Ship Through-Life Support _______________ 72 2.4 Top-down Structuring of Multi-Criteria Decision Problems ______ 84 2.4.1 Decision Analysis _____________________________________ 84 2.4.2 Effectiveness Analysis _________________________________ 85 2.4.3 Multi-Criteria Decision Making Techniques ________________ 88 2.5 Conclusion from the State of the Art Review __________________ 92 Chapter 3: Development of the Design for Support Evaluation Approach _ 96 7 Design for Support in the Initial Design of Naval Combatants 3.1 Introduction ____________________________________________ 96 3.2 Initial Proposals for the Design for Support Evaluation Approach ________________________________________ 97 3.2.1 Critical Path Method and Programme Evaluation and Review Technique ___________________________________________ 97 3.2.2 Prospect Theory-Based Real Option Analysis _______________ 99 3.3 The Proposed Design for Support Evaluation Approach ________ 102 3.3.1 Top-Down Structuring of the Evaluation of Naval Ship TLS __ 102 3.3.2 Developing Rational and Indicative