Static Stability Study of a Shallow Vee Hull Airboat for Sarawak Riverine Application

Static Stability Study of a Shallow Vee Hull Airboat for Sarawak Riverine Application Peter Yek Nai Yuh Master of Engineering (Mechanical Design & Computer Simulation) 2014

Static Stability Study of a Shallow Vee Hull Airboat for Sarawak Riverine Application Peter Yek Nai Yuh This thesis is submitted in partial fulfillment of the requirements for the Master of Engineering Faculty of Engineering UNIVERSITI MALAYSIA SARAWAK JUN 2014

I declare that I have read through this project report and to my opinion this project report is sufficient in term of scope and quality for the purpose of awarding the degree of Master of Engineering Signature:.. Name of Supervisor: ASSOC. PROF. DR HJ. MOHAMMAD OMAR ABDULLAH @ MAK KHOON LING Signature:.. Name of Co-supervisor: ERVINA JUNAIDI Title: Static Stability Study of Shallow Vee Hull Airboat For Sarawak Riverine Application Date: JUN 2014

I declare that this project report entitled Static Stability Study of a Shallow Vee Hull Airboat for Sarawak Riverine Application is the result of my own work except as cited in the references. The report has not been accepted for any degree and is not currently submitted in candidature of any other degree. Signature:.. Name of Candidate: Peter Yek Nai Yuh Date: JUN 2014

ACKNOWLEDGEMENTS First at all, I would like to thank God for all the blessings and strength that He had granted me upon completing this project. Secondly, I would like to express my appreciations to my supervisors, Prof. Dr. Mohammad Omar Abdullah and Ms. Ervina Junaidi, for their support, advice and help in the completion of this project. I also take this opportunity to thank them for spending their time in helping me to prepare this thesis. I would like to express my sincere gratitude to Prof. Dr. Sinin Hamdan and Mr. Peter Kuek for their kind assistance, helpful advices and supports in the boat design and overall airboat study, respectively. I am indebted to my family for providing me with the opportunity to further my study. Special thanks to my parents, Mr. Yek Siu Tak and Mrs. Ting Heng Ing whom have always respected and supported me in whatever decision that I made. Last but not least, I am deeply grateful to all my fellow friends, especially Mr. Cyril Jourbert, Ms. Loo Yee Ling and Mr. Kong Wen Keit for their helpful initial joint-study and priceless suggestion. Without them, it is impossible for me to complete this study successfully. i

Abstract This research aims to evaluate and explore the alternative of water transport varieties. Sarawak with riverine condition has shown a high potential of airboat application and development prospect as transportation is essential to bring people closer. This research acts as a preliminary work that aims to take a fresh look on the Static stability of existing Shallow Vee hull and follow with the PROLINES simulations for another two types of hull designs, which are Flat Bottom and Modified hull. Centre gravity (KG), metacentric height (GM) and metacentre above centre of buoyancy (BM) have shown the major influencing parameters manipulating the static stability of airboat. Besides that, an airboat with Shallow Vee hull was made for the stability performance testing in UNIMAS s pool, and it has given an acceptable range of testing results. Rpm of propeller, fuel consumption and wind speed have been measured before hand. Subsequently airboat is operated to measure the average speed and observed the overall stability during the turning. Naval architecture software, PROLINES is used for simulation work of different displacement and type of hulls. Simulation results have evaluated the airboat hydrostatics and statics stability performance. As a result, Flat Bottom and Modified hull gives merits of static stability compared to Shallow Vee hull. ii

Abstrak Penyelidikan ini bertumpu pada penilaian dan meneroka untuk mempelbagaikan pengangkutan air. Keadaan Sarawak yang penuh dengan sungai dan kawasan paya menghulurkan penggunaan dan kemajuan airboat kerana pengangkutan teresebut menghubung antara satu sama lain. Penyelidikan ini sebagai usaha asal untuk menilai kestabilan melalui PROLINES terhadap hull yang berbentuk Vee cetek, rata, dan direka semula. Pusat graviti, ketinggian metacentric dan jarak metacentre dari titik keapungan merupakan tiga parameter yang memberi kesan yang utama kepada kestabilan keseluruhan. Airboat dengan hull yang berbentuk vee cetek telah memberi keputusan yang memuaskan semasa menjalani kajian pretasi stabiliti di kolam UNIMAS. Selain itu, pusingan kipas, penggunaan petrol dan kelajuan angin yang dihasilkan oleh kipas telah diuji. Kelajuan dan keseimbangaan keseluruhan juga dipertimbangkan semasa airboat membuat pusingan. Dengan menggunakan perisian PROLINES, proses stimulasi telah dijalakan untuk menilai keseimbangan kapal dengan berat yang berlainan. Di samping itu, keseimbangan hull yang berlainan juga dinilai dari segi hidrostatik dan statik keseimbangan. Keputusan telah menunjukkan kapal yang rata dan direka semula memberi keputusan simulasi yang memuaskan dan lebih baik dibandingkan dengan bentuk yang Vee cetek. iii

TABLE OF CONTENT Page DECLARATION ACKNOWLEGMENT ABSTRACT ABSTRAK TABLE OF CONTENT LIST OF TABLES LIST OF FIGURES LIST OF ABBREVIATIONS LIST OF SYMBOLS I II III IV VIII IX XI XII CHAPTER ONE INTRODUCTION 1.1 Introduction 1 1.2 Sarawak Inland Waterway Transport 2 1.3 Essential of the Research 5 1.4 Objectives of the Research 6 1.5 Scope of the Research 7 1.6 Structure of the Thesis 8 CHAPTER TWO LITERATURE REVIEW 2.1 Review of Sarawak Riverine Condition 9 2.2 Review of Sarawak Inland Waterway Transport 10 2.3 Review of Airboat s Application 12 iv

2.4 Review of Airboat s Performance Research 15 2.5 Review of hull Stability Research 16 2.6 Evaluation of the Static Stability Performance 18 2.6.1 Calculation of Righting Arm (GZ) 18 2.6.2 Righting Arm Graph 22 2.7 PROLINES Simulation Review 24 CHAPTER THREE METHODOLOGY 3.1 Introduction 26 3.2 Flow Chart of Methodology 27 3.3 Parametric Measurement 28 3.3.1 Dimensional Parameter of Existing Shallow Vee hull 28 3.3.2 Inclining Test 30 3.4 PROLINES Simulation 33 3.4.1 Setting the Load Water Level (LWL) 35 3.4.2 Calculate the Hydrostatic and Stability Data 36 3.5 Initial Performance Testing 37 CHAPTER FOUR RESULTS AND ANALYSIS 4.1 Introduction 39 4.1.1 Overview of Constructed Airboat 40 4.2 Parameters Measurement and Calculations 42 4.3 Inclining Testing for Shallow Vee hull 42 v

4.3.1 Initial Setting 42 4.3.2 Graph and GM Calculation 42 4.4 PROLINES Simulation 44 4.4.1 Hull Drawing 44 4.4.1.1 Drawing with Buttock, Waterline and Station lines 44 4.4.1.2 B-splines Drawing 46 4.4.1.3 Render Hull 48 4.4.2 Hydrostatic Simulation with Different Type of Hulls 49 4.4.3 Static Stability Simulation with Different Type of Hulls 56 4.4.3.1 Wave Drag 56 4.4.3.2 Friction Drag 57 4.4.3.3 Righting Arm Curve 58 4.4.3.4 Metacentre Radius (BM) Curve 60 4.4.3.5 Metacentre Height (GM) Curve 61 4.5 Overall Performance Testing 64 4.5.1 Rpm Measurement 64 4.5.2 Fuel Consumption Measurement 65 4.5.3 Wind Velocity Measurement 66 4.5.4 Airboat Speed Measurement 67 vi

CHAPTER FIVE CONCLUSION 5.1 Introduction 68 5.2 Conclusion 68 5.3 Recommendations for Further Works 70 REFERENCES 71 APPENDIX A Inclining experiment APPENDIX B Hydrostatics data with different displacement simulation APPENDIX C Stability simulation results of different types of hull APPENDIX D Performance testing APPENDIX E Related publication (Journal paper) APPENDIX F Conference paper vii

LIST OF TABLES Table 3.1 Airboat part label 28 Table 3.2 Dimension of existing Shallow Vee hull 30 Table 4.1 General information and dimension of existing Shallow Vee hull 41 Table 4.2 The total weight calculation of the airboat 41 Table 4.3 (a) Initial setting for the inclining experiment 43 Table 4.3 (b) Calculation of the GM values from the inclining experiment 43 Table 4.4 Hydrostatic data of Flat Bottom hull 50 Table 4.5 Hydrostatic data of Shallow Vee hull 52 Table 4.6 Hydrostatic data of Modified hull 54 Table 4.7 Advantages and disadvantages of different hull design 63 viii

LIST OF FIGURES Figure 1.1 Map indicating major navigable rivers in Sarawak 4 Figure 2.1 Metacentre above centre of buoyancy 18 Figure 2.2 Wall sided formula 20 Figure 2.3 Stability curve 22 Figure 3.1 Flowchart of research methodology 27 Figure 3.2 The airboat parts and ballasts 28 Figure 3.3 (a) The body view of existing Shallow Vee hull 29 Figure 3.3 (b) The profile view of the existing Shallow Vee hull 29 Figure 3.3 (c) The plan view of the existing Shallow Vee hull 29 Figure 3.4 Flow chart of PROLINES Simulation 33 Figure 3.5 (a) Edit with visual vertex editor 34 Figure 3.5 (b) Example of stability calculation dialog 34 Figure 3.6 (a) Tachometer used to check the rpm of propeller 37 Figure 3.6 (b) Fuel consumption measurements 37 Figure 3.6 (c) Wind velocity measured by using anemometer 37 Figure 3.6 (d) Real constructed airboat test run 37 Figure 4.1 (a) Overall drawing of constructed airboat by CATIA 40 Figure 4.1 (b) Back view of constructed airboat by CATIA 40 Figure 4.2 Results of the inclining experiment 43 Figure 4.3 (a) The Flat Bottom hull with stations, waterlines and buttock lines view 45 Figure 4.3 (b) The Shallow Vee hull with stations, waterlines and buttock lines view 45 Figure 4.3 (c) The Modified hull with stations, waterlines and buttock lines view 45 Figure 4.4 (a) The Flat Bottom hull with B-splines view 47 ix

Figure 4.4 (b) The Shallow Vee hull with B-splines View 47 Figure 4.4 (c) The Modified hull with B-splines view 47 Figure 4.5 (a) 3D Rendered Flat Bottom Hull 48 Figure 4.5 (b) 3D Rendered Shallow Vee hull 48 Figure 4.5 (c) 3D Rendered of Modified Hull 48 Figure 4.5 (d) 3D Bottom part of Modified Hull 48 Figure 4.5 (e) 3D Rendered of Body View of Modified hull 48 Figure 4.6 Hydrostatic curve of Flat Bottom hull 51 Figure 4.7 Hydrostatic curve of Shallow Vee hull 53 Figure 4.8 Hydrostatic curves of Modified hull 55 Figure 4.9 The wave drag Vs. velocity 56 Figure 4.10 The friction drag Vs. velocity 57 Figure 4.11 The value righting arm Vs. heeling angle 58 Figure 4.12 The value of longitudinal of BM versus heeling angles 60 Figure 4.13 The value of transverse of BM versus heeling angles 60 Figure 4.14 The value of longitudinal of GM versus heeling angles 61 Figure 4.15 The value of transverse of GM verses heeling angles 62 Figure 4.16 Fuel consumption vs rpm 65 Figure 4.17 Wind speed vs rpm 66 Figure 4.18 The airboat speed vs. Time 67 x

LIST OF ABBREVIATIONS A M Area of the immersed portion of the midships A Area of the waterplane WP B B Beam Breath of the submerge part BM C M C B C WP D F b GM KG KM LOA Metacentre above centre of buoyancy Midship section coefficient Block coefficient. Waterplane coefficient Depth Freeboard Transverse metacentric height Centre of gravity Transverse metacentre above keel, Length overall L Length on the waterline WL LWL T f T T T p W Length on waterline Draft forward Draught of the submerge part Draught Static thrust of propeller Displacement xi

LIST OF SYMBOLS immersed volume m 3 θ Deadrise / pitch angle specific gravity m/s 2 Heeling angle static efficiency angular speed of propeller rad s 1 xii

CHAPTER ONE INTRODUCTION 1.1 Introduction Sarawak is known as The land of many rivers (Staub et al, 2000). The rivers provide a natural means of transportation and communication which connect the rural areas and the urban areas that are not accessible through the land transport. Many rivers in Sarawak are lined with longhouses and rainforest, making a safari down these rivers a unique experience, especially for visitors and tourists from urban or metropolitan cities. According to information and statistic from the Adventure in Sarawak, (2006), the main attractions of tourism industry in Sarawak are the longhouses, which serve as homes to the local tribe of Sarawak. The rainforest is also a home to an incredible variety of more than 8,000 species of flora and over 20,000 fauna, the majority of which are insects. Some of the most popular river journeys are along the Skrang, Lemanak, Batang Ai, and Rejang rivers. Due to the above, boat plays a very important part in Sarawak water transportation. This means of boat transportation is limited to the popular conventional boat with underwater propeller. The conventional boat, however, is always limited by water level and could not compromise with the large size of unwanted objects such as woods and seaweed. Airboat is having above water, air-propelled hull thus free from the conventional river conditions. It is an alternative way to conventional water transportation. This study includes the initial analysis on both hydrostatics data and static stability of the Flat bottom, Shallow Vee and Modified hull. 1

1.2 Sarawak Inland Waterway Transport Sarawak is the largest state in Malaysia, making up to some 37.5% of the country's total area. The State is divided into eleven Administrative Divisions. Sarawak is characterised by an extensive network of navigable rivers shown in Figure 1.1, which potentially form an Inland Waterway Transport (IWT) System. Sarawak has a total of 55 rivers with a combined length of approximately 5,000 km of which 3,300 km are navigable. Of all the rivers in Sarawak, the Batang Rajang is the most important with a total length of 567 km; it is the longest river in Malaysia. The other major navigable rivers comprise the Batang Baram, Batang Kemena, Batang Tatau, Sungai Limbang, Batang Lupar, Batang Sadong and Sungai Sarawak In some rural areas, boat services are the only means of public transport. The state s river transport system has great significance to the large section of Sarawak s population who live in the interior and along the coast. Much of Sarawak s rural population relies on rivers for transportation. Express boat services utilize the many waterways inland to get to rural areas inaccessible by road. Rajang River is the longest river in Malaysia. It has a total length of 760 km with a complex river system, originated from Iran Mountains. It drains a catchment area of 51,237 km 2 and consists of large network that leads to minimum gauging station. Rajang River is connected to a few towns from upstream, namely Belaga and Kapit while towards the downstream, namely Song, Kanowit, Sibu, Sarikei, Tanjung Manis and Daro. The Inland water transport system plays a significant role as it is the primary means of communication for a large section of the population living in the interior and along the coast of Sarawak. 2

There is an urgent need to develop the riverine transport in Sarawak. The impact of developing riverine transportation will not only improve access to basic amenities, such as health and educational services, but also indirectly enhances the local economic growth. 3

..-- KALIMANTAN Figure 1.1 Map indicating major navigable rivers in Sarawak (DID, 2010) 4

1.3 Essential of the Research Airboat has great potentials in its development and application in Sarawak. Therefore more specific researches and observations need to be done in this field. Some alternatives water transportation are urgently needed to be worked out to meet the needs. Consequently, their daily lives are very much constricted by the river tidal period and its geographical condition. Water transportation is still playing a very important role in some rural areas such as Kapit and Long Lama where land transportation is still not readily available in these areas due to mountainous condition. The main objective of this research is to study the alternative of water transportation in Sarawak. Some observation on the Sarawak riverine condition has been stated in the background study. Airboat plays a very important role for ecology researches as far as the local riverine and mangrove ecology conditions are concerned. From the initial study conducted, airboat can also be a useful means to emergency usage such as life saving. It can be very useful when flood occurs at areas along Sarawak Kanan River and other tidal rivers. Further research and modification of the airboat is carried out in this work to analyze and simulate the Sarawak riverine condition. The challenging part for the airboat design is that the engine used to propel the propeller must install with a certain height from the deck of the hull, in order to improve aerodynamics efficiency. For that purpose, detail static stability analysis of the airboat is done to improve the airboat operational safety. Initially the airboat with Shallow Vee hull was studied and tested for its stability. The Shallow Vee is found to have less overall stability and lower hydrostatic performances as 5

compared to the Flat Bottom and Modified hull. The performance result is subsequently verified via PROLINES simulations. This research has taken a Shallow Vee to analyze the static stability performance and use computer simulation to simulate another two types of hulls. Every type of hull has its own advantages and disadvantages. Flat Bottom hull is widely used for airboat application purpose at many countries such as United States; however in the present study, Shallow Vee hull is proposed to investigate its performance feasibility for Sarawak water transport. Inclining experiment has been conducted for the existing Shallow Vee hull to calculate the Metacentric height (GM). Comparison study is carried out on the Flat Bottom, Shallow Vee and Modified hull for overall airboat usages performance. This is done by simulation works where the Prolines software is employed to investigate their hydrostatic and stability performance. Results from the simulation are very important to assure their safety requirements. 1.4 Objectives of the Research The research emphasis on the static stability analysis for the airboat application on the three types of hull designs, i.e. flat bottom, Shallow Vee and modified hull. These simulations could provide useful information of airboat application under Sarawak riverine condition. The study is achieved by considering the following objectives: 1. To conduct literature review to identify previous relevant works on water transportation applications and it s applicable in Sarawak Riverine. 2. To conduct a study on the initial performance of the Shallow Vee hull airboat. 6

3. To investigate and compare the advantages and disadvantages of Flat Bottom hull, Shallow Vee hull and Modified hullbased on PROLINES simulation results toward airboat application. 1.5 Scope of the Research There are many aspects of research areas can be done towards airboat. Hydrostatics parameters and factors needed to be considered, in order to have the better airboat design. Therefore, the combination with type and size of hull, engine s capability, propeller applied are major factor that need to be carefully consider. Improvement of particular aspect will give a certain impact to the airboat performance. Besides that, investigation and improvement of the airboat performance in the aspect of speed, stability, quietness, or maneuverability also need to be clarified. However, the major constrain factor to the airboat performance need to be define earlier. During initial stage of the airboat development for Sarawak riverine application, static stability of the airboat is consider as the bottleneck of the airboat performance and it become foremost parameter that need our attention. According to Mabie & Reinholtz (1987), stabilization and vibration study of the boat need to be considered in the design state and, a number of tests need to be done to have an acceptable performance of the engine and airboat (Michael, 2002). This including boat stability when travel in straight line and when turning, engine air thrust measurements, etc. 7

1.6 Structure of the thesis This thesis consists of five chapters. Chapter one is the introduction, which review the Sarawak Riverine condition, the need of river transportation development, purpose and general overview of the project to the reader. Chapter two is the literature review of the previous works and researches of airboat static stability. Chapter three presents the methodology to carry out the evaluation of existing Shallow Vee hull airboat s static stability. A major portion of this chapter is dealing with the usage of PROLINES software to compare the static stability performance with Flat Bottom and modified hull. Chapter four consists of results analysis gathered by experiment performance from inclining test and PROLINES simulations. Chapter five is the conclusion and recommendation of this research works. 8