21st INTERNATIONAL TOWING TANK CONFERENCE

Transcription

1 i^poratoflum v^jfu- Schee^jsbycfrómechanJca Archief Mekelweg CD Delft T«bOt«-78S87»-Fait » P J Volume 1 21st INTERNATIONAL TOWING TANK CONFERENCE Proceedings Volume I Trondheim, Norway September 15-21,1996 NTNU [ S M f f i The Norwegian University Norwegian Marine Technology of Science and Technology Research Institute

2 ITTCK 1996 J 2Ist INTERNATIONAL TOWING TANK CONFERENCE Uboratorium voor Seheepshydromochanlca j Afchiof Mekefwsg 2, 2628 CD 'lo'.ff Wb « » Fat 015 7^^ 5 Organizing Committee Mr. Arnold K. Hansen Norwegian Marine Technology Research Institute Dr. Erling Huse Norwegian Marine Technology Research Institute Dr. Odd Faltinsen The Norwegian University of Science and Technology Sponsors MARINTEK Advanced Production and Loading A/S Det norske Veritas Classifications AIS Kvcerner Masa-Yards Inc. Royal Norwegian Ministry of Foreign Affairs Research Council of Norway SINTEF Editor Dr. Erling Huse Norwegian Marine Technology Research Institute

3 KiTTCR L 1996 J PREFACE On behalf cf MARINTEK and The Norwegian University of Science and Technology I take great pleasure in welcoming the 21st ITTC to Bergen and Trondheim. The Technical Committees and the organisers have akeady spent considerable effort in preparing the Proceedings and the Conference. It is now up to all of us to make it a fruitful arrangement, sociauy as well as professionally. Over the pastfewdecades we have witnessed a general technological development that seems to be ever-accelerating. TTietiueeyears that have passed since the 20tii ITTC have been no exception in tius respect. Looking more specifically at the area of interest to tiie ITTC community we have for instance a development witiiin information technology that changes our lives and activities significantiy. Awareness of tiie necessity to protect the environment has an impact on ship design. Interest in high speed.ships is no longer limited to naval applications. They have become an important commercial market for tiie shipping and shipbuilding industry, and tiius also more important for tiie ITTC member organisations. In the offshore industry tiie development of oil fields in very deep waters poses new challenges to us regarding numerical hydrodynamics as well as model testing techniques. Business-wise the rapid changes may represent ups and downs in the market that can be hard to predict. An overall conclusion is tiiat in order to survive our member organisations must be flexible and capable of quick response to changes in tiie industry. In tiiis situation it is important tiiat tiie ITTC be an efficient tool for the member organisations, and not an obstacle to rapid technological changes. Considering tiie present interest in ITTC shown by tiie member organisations it is my sincere belief tiiat we shall manage to maintain and augment tiie role of ITTC as tiie efficient tool we want it to be. The 21st ITTC is deviating somewhat from traditional arrangements in tiie sense that it takes place partly on board a ship. We hope tiiat you will find titis arrangement, togetiier witii tiie technical and social programs interesting, and tiiat your visit to Norway will be a rewarding and memorable one. Managing Director, MARINTEK Chair, Executive Committee, 21st ITTC

4 L 1996 J Table of Contents Proceedings ofthe 21'' ITTC Volume 1 Preface Committees of the 21st ITTC i I Report of the Advisory Council 3 1 Membership and Meetings 3 2 Activities and Recommendations of the Advisory Council 3 3 Officers for tiie 22nd Advisory Council 5 Report of the Executive Committee 7 1 Introduction 7 2 Obituaries 7 3 Committee Membership 9 4 Committee Meetings 9 5 Committee Decisions 9 Report of the Seakeeping Committee 11 1 Membership and Meetings 11 2 Recommendations of the 20th ITTC 11 3 Wave Generation and Beach Characteristics in Experimental Facilities 12 4 Numerical Predictions of Forces and Motions....' 13 5 Seakeeping in Extreme Weather Conditions 17 6 Nonlinear Rolling and Capsizing 22 7 Experimental and Testing Techniques for Seakeeping for HSMVs 27 8 Seakeeping Performance of Twin Hull Configurations 30 9 Full Scale Measurements and Real Time Forecasting Seakeeping Assessment Uncertainty Analysis and Validation Procedures Conclusions and Recommendations References 44 Report of the Cavitation Committee 63 1 Membership and Meetings 63 2 Recommendations of the 20th ITTC 64 3 Introduction 64 4 Measurements of Hull Pressure Fluctuation 65 5 Cloud Cavitation 72 6 Mechanism, Scale Effects, and Delay of Vortex Cavitation 80 " 7 Computational Efforts to Predict Cavitation 92 8 Cavitation Nuclei Effects on Inception 95 9 High-speed Cavitation Peifomiance 105

5 II pttck L 1996 J 10 Blade Cavitation Pattems Quality Control Conclusions to the Conference Recommendations to the Conference 117 References 117 Report of the Propulsor Committee General Comparative Experiments on Steady State Reynolds Number Effects 128 * 3 Evaluation of Experimental and Theoretical Prediction Techniques for Unconventional Methods of Propulsion such as Tip Plate, Ring and Ducted Propellers Provide Advice on Boundary Layer Tripping on Propulsor Siufaces that exhibit Significant Viscous Effects in Model Wake Propulsor Literature Database Guide for the use of LDV for the Collection of Propulsor Data Suitable for Validation of Numerical Calculations High Speed Propulsor and Interaction Effects for High Speed Marine Vehicles Developments in the use of Panel Methods and RANS Equation Codes for PropulsorsI59 9 Reynolds Number Dependency of Lift Coefficient for Wing Sections Standard Procedures and Codes Conforming to ISO Conclusions Recommendations to the Conference References 177 Report of the Waterjets Group General Literature Survey Discussion of Possible Power Prediction Methods for Watcrjet Propulsion System..." Recommendations to tiie Conference References 198 Appendix A Possible Power Preciction Metiiod for Waterjet systems 200 Appendbc B Proposed List of ITTC Symbols for Waterjets 204 Appendix C Direct Thrust Measurement Method 205 Appendix D Sensitivity Aspect 208 Report ofthe Performance in Ice-Covered Waters Committee General Standard Test Methods for Model Ice Properties Recommended Procedures for Ice Model Tests Recommendations for Ship Trials in Ice Analysis of tfie Cylinder Tests Model Propulsion Tests in Ice BibUography of Ships in Ice References Recommendations to the Conference 270 Report of the Ocean Engineering Committee General Survey of Existing Test Techniques and Procedures Exttapolation Technique for full Scale Low-Frequency Damping Characteristics of Model Tests Recommended Test Procedures Review on Numerical Models for Time-Domain Simulation of Slow-oscillating Motions of Offshore Structures Short-crested Wave Experimental Techniques Combination of Exffeme Wind, Wave and Current Parameters Wind and Current 296

6 nzztcr L 1996 J» 9 Validation of the Mean Wave Drift Forces using the Nearfield and Farfield Methods Short Review of Ocean Engineering Research of Interest to the ITTC Conclusions and Recommendations 305 References 307 Report of the Quality Control Group General Activities of 2 IstlTTCQCG Report of Technical Committees ' Work on Quality Control Activities ISO Certification Process ISO Certifiation - tiie Current Trend Conclusions Recommendations to the Conference References 327 Appendix A: Example: Current Marin Quality Assurance System Document 327 Appendix B: Sample DTMB ISO 9000 Procedure 329 Appendix C: Sample DTMB ISO 9000 Work Instruction 333 Report of the Symbols and Terminology Group General Work of the Group Conclusions Recommendations to the Conference,, 346 Report of the Manoeuvrability Committee General '' Special Groups ' Prediction of Forces Simulation of Dynamics : Non-conventional Craft 36\ 6 Validation, Scale Effects and Full Scale Trials 36% 7 Ship Operation & Safety, IMO Standards Evolution of Model Testing Methods Recommended Standard PMM Test Procedure Conclusions of the Committee Referances 382 Report of the Powering Performance Committee 3S»9 1 Membership and Meetings Recommendations of the 20th ITTC Introduction. ' Standard Method for Analysis of Full Scale Trial Results... AQ\ 5 Standardize Uncertainty Analysis for Representative Testing Metiiods for Powering Predictions Conformance to ISO Self-propulsion Test Methods for Separation-prone Hull Foirns Reynolds Nimiber Dependency of Form Factor A\9 9 Powering Predictions for Ships Fitted with Conu-arotating Propellers and Propellers with Stators Conclusion ].... [ [ Recommendations to the Conference Acknowledgments 431 Appendix I - An Updated Guide for Speed/Powering Trials 431 Appendix n - Propulsion Test Metiiods References "'' 435

7 IV Report of the Resistance and Flow Committee Introduction A Naval Architect's view General Trends in Computational Fluid Dynamics CFD Uncertainty Analysis A User's Guide Standard for CFD Application CFD as an Assistant to Model Experiments Conclusions 8 Recommendations to the Conference 500 References Report ofthe High-Speed Marine Vehicles Committee General Review of Research in HSMV safety of hiterest to tiie ITTC 5 lö 3 Conclusions and Recommendations References 544 Appendices 1. The Rules of the Organization 1. Aims 2. Activities 3. Membership ^^J 4. Organisation 5. Groups ^^T 6. Meetings - irz 7. Compositionof Executive Committee based on Geographic Areas 8. List of Geographic Areas r ^ ^ ^ l ^ t 9. General Additional Guidelines for tiie operation of tiie ITTC ^oz> 2. New Technical Committee Structure 1 Structure of tiie Technical Committees J^/ 2 Terms of Reference of General and Specialist Committees / 3 Mechanism for Identifying New Specialist Technical Committees ^o» 4 Tasks of Speciahst Committees of 22 " ritc 56K 3. Index of mc Documents ^'^ 1. ITTC Organisation 2. Proceedings 3. ITTC Publications 4 ITTC Addresses ^" 4. Member Organisations 5. Delegates invited to the 21" TTTC ^^"^ 6. Guidelines for Preparation of Technical Committee and Working Group Reports Overview 2. Materials 3. Page Geometry 4. Text Matiiematics ^g-j 6. Graphic material ' 1. References 579

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