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A Procedure for the Dynamic Positioning Estimation in Initial Ship-Design

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A Procedure for the Dynamic Positioning Estimation in Initial Ship-Design A Procedure for the Dynamic Positioning Estimation in Initial Ship-Design Syed Marzan Ul Hasan Master Thesis presented in partial fulfillment of the requirements for the double degree: “Advanced Master in Naval Architecture” conferred by University of Liege "Master of Sciences in Applied Mechanics, specialization in Hydrodynamics, Energetics and Propulsion” conferred by Ecole Centrale de Nantes developed at University of Rostock, Germany in the framework of the “EMSHIP” Erasmus Mundus Master Course in “Integrated Advanced Ship Design” EMJMD 159652 – Grant Agreement 2015-1687 Supervisor: Dr. Robert Bronsart , University of Rostock, Germany Reviewer: Dr. Lionel Gentaz, École Centrale de Nantes, France Rostock, February 2018 P 2 Syed Marzan Ul Hasan (This page is intentionally left blank) Master Thesis developed at University of Rostock, Germany Declaration of Authorship I, …………………………………………………………………………………………….Syed Marzan Ul Hasan declare that this thesis and the work presented in it are my own and has been generated by me as the result of my own original research. ………………………………………………………………………………………………………… A Procedure for the Dynamic Positioning Estimation in Initial Ship-Design ………………………………………………………………………………………………………… I confirm that: 1. This work was done wholly or mainly while in candidature for a research degree at this University; 2. Where any part of this thesis has previously been submitted for a degree or any other qualification at this University or any other institution, this has been clearly stated; 3. Where I have consulted the published work of others, this is always clearly attributed; 4. Where I have quoted from the work of others, the source is always given. With the exception of such quotations, this thesis is entirely my own work; 5. I have acknowledged all main sources of help; 6. Where the thesis is based on work done by myself jointly with others, I have made clear exactly what was done by others and what I have contributed myself; 7. Either none of this work has been published before submission, or parts of this work have been published as: [please list references below]: 8. I cede copyright of the thesis in favour of the University of Rostock ; Signed: ………………………………………………………………………………………………………… 15/01/2018 Date: ……………………………………………………………………………………………. P 4 Syed Marzan Ul Hasan (This page is intentionally left blank) Master Thesis developed at University of Rostock, Germany A Procedure for the Dynamic Positioning Estimation in Initial Ship-Design 5 TABLE OF CONTENTS NOMENCLATURE ................................................................................................................................ 11 ABSTRACT ............................................................................................................................................. 14 1. INTRODUCTION .......................................................................................................................... 17 1.1 Use of Dynamic Positioning ................................................................................................ 17 1.2 Significance of DP ............................................................................................................... 17 1.3 DP in Initial Ship Design ..................................................................................................... 19 1.4 Rationale for the present work ............................................................................................. 20 1.5 Final Goals or Objectives of the technical work .................................................................. 21 1.6 Organization of the Thesis ................................................................................................... 22 2. BACKGROUND STUDY .............................................................................................................. 23 2.1 Literature Review ................................................................................................................. 23 2.2 Standards and Guidelines ..................................................................................................... 23 2.3 Environmental Constraints ................................................................................................... 24 2.3.1 Wind Loads ........................................................................................................................... 25 2.3.2 Current Loads ...................................................................................................................... 26 2.3.3 Wave drift forces .................................................................................................................. 27 2.4 Operational Factors .............................................................................................................. 28 2.5 Dynamic Capability and allowance ..................................................................................... 29 2.6 Propulsion Arrangement and Constraints ............................................................................ 30 2.7 Interaction Mechanism ......................................................................................................... 30 2.8 Optimization Problem .......................................................................................................... 33 2.9 Effect of Type of Vessels ..................................................................................................... 34 2.10 Full thrust and worst case failure considerations ................................................................. 35 2.12 Traditional DP Scaling (ERN/PCR) ..................................................................................... 36 3. METHODOLOGY AND CONCEPT DEVELOPMENT .......................................................... 37 3.1 Static Force Balance ............................................................................................................. 37 3.2 Sign Convention ................................................................................................................... 39 3.3 Formulation of the Optimization Module ............................................................................ 41 3.4 Vessel Particulars ................................................................................................................. 43 3.4.1 Selection of Main Parameters ............................................................................................ 43 5 P 6 Syed Marzan Ul Hasan 3.4.2 Dynamic Allowance ............................................................................................................. 44 3.4.3 Maximum Wind Speed ......................................................................................................... 44 3.5 DP Capability Plot ............................................................................................................... 45 3.5.1 Type of Polar Plots .............................................................................................................. 45 3.6 Main Challenges .................................................................................................................. 47 3.7 Summary of the technical work ........................................................................................... 47 4. EXTERNAL FORCES ................................................................................................................... 49 4.1 Wind ..................................................................................................................................... 49 4.1.1 Wind load coefficients ......................................................................................................... 50 4.2 Current ................................................................................................................................. 54 4.3 Waves ................................................................................................................................... 58 4.3.1 Wind-wave correlation ........................................................................................................ 59 4.3.2 Wave coefficients and Forces ............................................................................................ 61 4.4 Additional Forces ................................................................................................................. 66 4.6 Resultant Components and Actual Forces ........................................................................... 67 5. THRUSTERS .................................................................................................................................. 68 5.1 Transverse thrusters ............................................................................................................. 70 5.1.1 Estimation of thrust for Transverse Thrusters ................................................................. 71 5.3 Azimuth thrusters ................................................................................................................. 72 5.3.1 Estimation of the directional thrust for Azimuth Thrusters ........................................... 73 5.3.2 Interaction effects for Azimuth Thrusters ......................................................................... 73 5.5 Propeller and Rudder ........................................................................................................... 75 5.5.1 Description ..........................................................................................................................
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