The Experts below are selected from a list of 9102 Experts worldwide ranked by ideXlab platform
Baoji Zhang - One of the best experts on this subject based on the ideXlab platform.
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computational fluid dynamics based Hull Form optimization using approximation method
Engineering Applications of Computational Fluid Mechanics, 2018Co-Authors: Shenglong Zhang, Baoji Zhang, Tahsin Tezdogan, Yuyang LaiAbstract:With the rapid development of the computational technology, computational fluid dynamics (CFD) tools have been widely used to evaluate the ship hydrodynamic perFormances in the Hull Forms optimization. However, it is very time consuming since a great number of the CFD simulations need to be perFormed for one single optimization. It is of great importance to find a high-effective method to replace the calculation of the CFD tools. In this study, a CFD-based Hull Form optimization loop has been developed by integrating an approximate method to optimize Hull Form for reducing the total resistance in calm water. In order to improve the optimization accuracy of particle swarm optimization (PSO) algorithm, an improved PSO (IPSO) algorithm is presented where the inertia weight coefficient and search method are designed based on random inertia weight and convergence evaluation, respectively. To improve the prediction accuracy of total resistance, a data prediction method based on IPSO-Elman neural network (NN) is proposed. Herein, IPSO algorithm is used to train the weight coefficients and self-feedback gain coefficient of ElmanNN. In order to build IPSO-ElmanNN model, optimal Latin hypercube design (Opt LHD) is used to design the sampling Hull Forms, and the total resistance (objective function) of these Hull Forms are calculated by Reynolds averaged Navier–Stokes (RANS) method. For the purpose of this paper, this optimization framework has been employed to optimize two ships, namely, the DTMB5512 and WIGLEY III ships, and these Hull Forms are changed by arbitrary shape deFormation (ASD) technique. The results show that the optimization framework developed in this study can be used to optimize Hull Forms with significantly reduced computational effort.
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the design of a Hull Form with the minimum total resistance
Journal of Marine Science and Technology, 2015Co-Authors: Baoji Zhang, Aiqin MiaoAbstract:In order to obtain a Hull Form which exhibits low resistance and highly-efficient energy-saving perFormance, the overall resistance should be calculated as the sum of wave-making and viscous resistance, in which the total resistance corresponds to the objective function whereas the Hull geometry parameters correspond to design variables. Apart from considering the limited conditions due to appropriate displacement, we further ponder over the boundary-layer viscous separation caused by additional constraints. We then proceed to apply the Nonlinear Programming Method (NLP) to determine the Hull Form with the minimum total resistance. This paper aims to optimize the streamlined design of the S60 so as to get an improved Hull Form in which lower resistance and smoother Hull lines are evident. This suggests that there is no significant increase in viscous resistance during the process of Hull Form optimization with the wave-making resistance as the objective function. Therefore, this confirms the feasibility of optimizing the Hull Form by the NLP method.
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research on theoretical optimization and experimental verification of minimum resistance Hull Form based on rankine source method
International Journal of Naval Architecture and Ocean Engineering, 2015Co-Authors: Baoji Zhang, Zhuxin ZhangAbstract:To obtain low resistance and high efficiency energy-saving ship, minimum total resistance Hull Form design method is studied based on potential flow theory of wave-making resistance and considering the effects of tail viscous separation. With the sum of wave resistance and viscous resistance as objective functions and the parameters of B-Spline function as design variables, mathematical models are built using Nonlinear Programming Method (NLP) ensuring the basic limit of displacement and considering rear viscous separation. We develop ship lines optimization procedures with intellectual property rights. Series60 is used as parent ship in optimization design to obtain improved ship (Series60-1) theoretically. Then drag tests for the improved ship (Series60-1) is made to get the actual minimum total resistance Hull Form.
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shape optimization of bow bulbs with minimum wave making resistance based on rankine source method
Journal of Shanghai Jiaotong University (science), 2012Co-Authors: Baoji ZhangAbstract:The Hull Form optimization concerns one of the most important applications of wave-making resistance theories. In recent years, scholars can determine the Hull Form by using the optimization method based on the computational fluid dynamics (CFD) and other mathematical techniques. In this paper, the Hull Form optimization method based on the Rankine source method and nonlinear programming (NLP) is discussed; in the optimization process, a Hull Form modification function is introduced to represent an improved Hull surface and to generate a new smooth Hull surface by changing its frame lines and bow stem profiles under the prescribed design constraints. Numerical example is given for a practical container Hull Form. Finally, shape optimization of bow bulls is shown for non-protruding and protruding bow bulls. This study presents a simplified and practical design method to the select frame lines of bow bulls.
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the optimization of the Hull Form with the minimum wave making resistance based on rankine source method
Journal of Hydrodynamics, 2009Co-Authors: Baoji ZhangAbstract:The Hull Form optimization concerns one of the most important applications of wave making resistance theories. In order to obtain a Hull Form with the minimum wave making resistance, an optimization design method based on the CFD is proposed, which combines the Rankine source method with the nonlinear programming (NLP). The bow-body shape is optimized with the minimum wave making resistance as the objective function. A Hull Form modification function is introduced to represent an improved Hull surface, which can be used to generate a new smooth Hull surface by multiplying it by the offset data of the original Hull surface. The parameters of the Hull Form modification function are taken as the design variables. Other constraint conditions can also be considered, for example, in optimizing the lines of the bow, appropriate displacements can be taken as the basic constraints. S60 Hull Form is selected as the original Hull. Three improved Hulls are obtained by optimal design. Rankine source method proves to be an effective method in ship Form optimization based on analysis of the resistance perFormance and lines of the improved Hull.
Hohwan Chun - One of the best experts on this subject based on the ideXlab platform.
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Hull-Form optimization using parametric modification functions and particle swarm optimization
Journal of Marine Science and Technology, 2016Co-Authors: Jungeun Choi, Hohwan ChunAbstract:The focus of this paper is on devising designer-friendly Hull-Form variations coupled with optimization algorithms. Hull-Form variations are carried out through parametric modification functions. Two kinds of representative optimization algorithms are considered here. One is the well-known sequential quadratic programming which is the derivative based. The other is particle swarm optimization which is the derivative free. The results applying these two algorithms to typical Hull-Form optimization problems are discussed in the paper. The technique using the parametric modification functions has been developed for modifying the ship’s geometry according to the widely recognized naval architect’s design practice. An original geometry can be easily deFormed through the change of the variables of the modification functions; and useful inFormation about the effect of the parameters is immediately obtained. Moreover, the variables of the modification functions can be considered as the design variables in the Formulation of the optimization problem. For the perFormance prediction of the Hull Form, WAVIS version 1.3 is used for the potential-flow and RANS solver. Computational results for both single- and multi-objective problems are presented.
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Hull Form optimization of ksuezmax to enhance resistance perFormance
International Journal of Naval Architecture and Ocean Engineering, 2015Co-Authors: Jongheon Park, Jungeun Choi, Hohwan ChunAbstract:ABSTRACT: This paper deploys optimization techniques to obtain the optimum Hull Form of KSUEZMAX at the conditions of full-load draft and design speed. The processes have been carried out using a RaPID-HOP program. The bow and the stern Hull-Forms are optimized separately without altering neither, and the resulting versions of the two are then combined. Objective functions are the minimum values of wave-making and viscous pressure resistance coefficients for the bow and stern. Parametric modification functions for the bow Hull-Form variation are SAC shape, section shape (U-Vtype, DLWL type), bulb shape (bulb height and size); and those for the stern are SAC and section shape (U-Vtype, DLWL type). WAVIS version 1.3 code is usedfor the potential and the viscous-flow solver. Prior to the optimization, a parametric study has been conducted to observe the effects of design parameters on the objective functions. SQP has been applied for the optimization algorithm. The model tests have been conducted at a towing tank to evaluate the resistance perFormance of the optimized Hull-Form. It has been noted that the optimized Hull-Form brings 2.4% and 6.8% reduction in total and residual resistance coefficients compared to those of the original Hull-Form. The propulsive efficiency increases by 2.0% and the delivered power is reduced 3.7%, whereas the propeller rotating speed increases slightly by 0.41 rpm.
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Hull Form development of a twin skeg large ro pax ferry
Journal of The Society of Naval Architects of Korea, 2012Co-Authors: Hwa Joon Lee, Hagsoo Jang, Chunbeom Hong, Sungmok Ahn, Hohwan ChunAbstract:A Hull-Form for a 32,000G/T class Ro-Pax ferry has developed in accordance with a need of ferry operators to reduce fuel oil consumption(FOC) due to the drastic increase in oil prices recently and strengthening of environmental rules and regulations such as CO2 emission. A twin-skeg type is applied as the Hull-Form in lieu of an open-shaft type in order to improve propulsion perFormance. In order to achieve this object, flow control devices are installed to reduce a propeller induced vibration which is a main reason to obstruct the application of twin-skeg type passenger vessels owing to an uncomfortable vibration level. Numerical simulation by using an in-house code and a commercial code (Fluent) has perFormed to find out an optimum design of the flow control devices and to check an improvement in cavity volume. Model tests in Samsung Ship Model Basin are carried out to evaluate propulsion perFormance with the developed twin-skeg type Hull and a reference Hull of open-shaft type. In conclusion, it is shown that the twin-skeg type Hull is better than the open-shaft in FOC by around 7% and in cavity volume by 20% as well.
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a study on the Hull Form design of semi planing round bilge craft
Journal of Ocean Engineering and Technology, 2010Co-Authors: Jung Gwan Lee, Hohwan Chun, Kwang Hyo Jung, Sungbu Suh, Inwon LeeAbstract:*Hanjin Heavy Industries & Construction Co. LTD., Busan, Korea**Dept. of Naval Architecture & Ocean Engineering, Dong-Eui Uni versity, Busan, Korea***Dept. of Naval Architecture & Ocean Engineering, Busan Natio nal University, Busan, Korea****Advanced Ship Engineering Research Center, Busan National U niversity, Busan, KoreaKEY WORDS: Semi-planing Hull Form 반활주형 선형, Round bilge 곡면 선저, Stern wedge 선미쇄기, Spray strip 물보라 억제장치, Model test 모형시험ABSTRACT:This study presents the design procedure for optimizing the sem i-planing Hull Form, including appendages, using numerical and experimental methods. Four different referenced semi-planing hu ll Forms were compared to determine their hydrodynamic perForma nces, and one of the Hull Forms was modified for optimum operation at high-speed conditions (0.4
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study on resistance perFormance of icebreaking cargo vessel in pack ice condition according to variation of synthetic ice thickness and Hull Form characteristics
Journal of The Society of Naval Architects of Korea, 2009Co-Authors: Seungho Lee, Hohwan Chun, Moonchan Kim, Juncheol Cho, Byungchul Shin, Unhwa JungAbstract:AbstractThe present paper deals with characteristics of resistance perf ormance according to the variation of synthetic ice thickness and Hull Form. The resistance test has been conducted with pack ice condition in Pusan National University towing tank. Stem angle has been chosen as main parameters for the variation of Hull Form charac teristics, which is the most important factor especially in icebreaking cargo vessel. The se rial comparisons of resistance test have been done with the variation of Hull Form parameter a s well as with the different thickness of synthetic ice. The different trend of resistance perFormances with increasing of stem angle has been shown at each synthetic ice thickness. The present test results is expected to be confirmed by comparing the test results in ice t ank in the near future. ※Keywords: Towing tank(예인수조), Icebreaking cargo vessel(쇄빙상선), Synthetic ice(합성 얼음), Stem angle(선수각), Waterline angle(수선면각), Thickness variation(두께변화)접수일: 2009년 6월 5일, 승인일: 2009년 9월 2일✝교신저자: kmcprop@pusan.ac.kr, 051-510-2401
Decheng Wan - One of the best experts on this subject based on the ideXlab platform.
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Hull Form optimization based on calm water wave drag with or without generating bulbous bow
Applied Ocean Research, 2021Co-Authors: Xinwang Liu, Weiwen Zhao, Decheng WanAbstract:Abstract In the ship design process, Hull Form design and optimization play an important role. In the research and engineering fields of Hull Form optimization, the resistance perFormance is most noticed among all the hydrodynamic perFormances. In this paper, we focus on the calm-water drag optimization for a high-speed slender Hull without a bulbous bow, and the generation of the bulbous bow is introduced in detail, such as the Hull Form deFormation methods and the knot-insertion procedure for the NURBS surface. Two optimization cases are given. In case 1, only shifting method is used, while in case 2, shifting and Radial Basis Function (RBF) methods are both used. During the hydrodynamic evaluation of the new sample Hulls, the potential flow solver is applied, and the verification and validation procedure is done at first. The genetic algorithm is used to obtain two optimal ships with minimum wave drag. Optimization results show that even when we do not generate a bulbous bow, the optimal Hull will have a relatively big decrease of the wave drag coefficient. However, favorable interference of the wave systems conducted by the generated bulbous bow can help reduce the wave drag coefficient to a greater extent, showing that the bulbous bow generation method proposed in this paper has potentials in the resistance optimization of the medium- or high-speed ship Hulls.
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linear reduced order method for design space dimensionality reduction and flow field learning in Hull Form optimization
Ocean Engineering, 2021Co-Authors: Xinwang Liu, Weiwen Zhao, Decheng WanAbstract:Abstract In the earlier stage of Hull Form optimization design, a series of design variables is usually needed to control the Hull shape, so as to find optimal Hull Forms with better perFormance. In the surrogate-based hydrodynamic perFormance optimization for ships, with the increase of the dimensionality of design space, the number of new sample Hulls to construct surrogate model needs to be larger, which will bring a large amount of calculation. Through reduced order method, the dimensionality of the optimization design space can be reduced while keeping the deFormation range of the original design space to a great extent, for instance, using the linear combination of a smaller number of bases to represent the deFormation range. In addition, in the later stage of Hull Form optimization design, flow field results of the new sample Hulls can be fully utilized to do the dimensionality reduction multi-physics field learning. In this paper, the principle of the Proper Orthogonal Decomposition method is used and briefly introduced, the steps of dimensionality reduction of the design space are shown then, and some important problems for the design-space dimensionality reduction in the specific field of Hull Form optimization, such as retainability of fixed control points, irrelevance of the relative order of data to dimensionality reduction results, and decision of the new design space range after dimensionality reduction, are deep analyzed. Furthermore, taking the resistance optimization of the modified Wigley ship as an example, the specific application and error analysis of the dimensionality reduction method for design-space dimensionality reduction in the earlier stage of Hull Form optimization and the multi-physics field learning in the later stage of Hull Form optimization are given, and the applicability and reliability of the method are demonstrated by analyzing the influence of mode order and sample number on reconstruction effect of the Hull shape or flow field, and the prediction effect of flow field for not-in-the-database new Hull Form in detail. Results show that the linear dimensionality reduction method can reduce samples needed for optimization, thus reduce the amount of calculation for the surrogate-based Hull Form optimization, and be used for quick prediction of multi-physics fields of any new Form in the design space. Furthermore, it can not only be applied to the sensitivity analysis or a Pareto frontier selection in comprehensive perFormance optimization of Hull Form based on CFD, but also be implemented in the real-time forecast of the flow field and influence analysis of the ship perFormance when adjusting the Hull Form (or Hull appendages).
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Hull Form optimization based on an nm cfd integrated method for kcs
International Journal of Computational Methods, 2020Co-Authors: Aiqin Miao, Decheng WanAbstract:This paper concerns development and illustration of a hydrodynamic optimization tool, OPTShip-SJTU, which contains four main components, i.e., Hull Form modifier, perFormance evaluator, surrogate m...
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neumann michell theory based multi objective optimization of Hull Form for a naval surface combatant
Applied Ocean Research, 2017Co-Authors: Xiaoyi Liu, Min Zhao, Decheng WanAbstract:Abstract A numerical multi-objective optimization procedure is proposed here to describe the development and application of a practical hydrodynamic optimization tool, OPTShip-SJTU. Three components including Hull Form modification module, hydrodynamic perFormance evaluation module and optimization module consist of this tool. The free-Form deFormation (FFD) method and shifting method are utilized as parametric Hull surface modification techniques to generate a series of realistic Hull Forms subjected to geometric constraints, and the Neumann-Michell (NM) theory is implemented to predict the wave drag. Moreover, NSGA-II, a muti-objective genetic algorithm, is adopted to produce pareto-optimal front, and kriging model is used for predicting the total resistance during the optimization process to reduce the computational cost. Additionally, the analysis of variance (ANOVA) method is introduced to represent the influence of each design variable on the objective functions. In present work, a surface combatant DTMB Model 5415 is used as the initial design, and optimal solutions with obvious drag reductions at specific speeds are obtained. Eventually, three of optimal Hulls are analyzed by NM theory and a RANS-based CFD solver naoe-FOAM-SJTU respectively. Numerical results confirm the availability and reliability of this multi-objective optimization tool.
Hassan Ghassemi - One of the best experts on this subject based on the ideXlab platform.
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effect of Hull Form coefficients on the vessel sea keeping perFormance
Journal of Marine Science and Technology, 2013Co-Authors: Mohsen Khosravi Babadi, Hassan GhassemiAbstract:This paper investigates the Hull Form of a high speed chine vessel based on a smart model, so as to observe the effect of variations in some geometrical parameters and Hull Form coefficients, such as Cwp and Cp, on sea-keeping response by means of numerical and experimental methods. For modeling, neural networks and polynomial fitting methods are combined to achieve sufficient accuracy in modeling. The effect of variations in Cwp and Cp on the hydrodynamic response, which is calculated by the modified strip theory method and Pierson-Moskowitz (PM) wave spectrum, is illustrated. The main assumption of the paper is that variations in Hull Form parameters are so slight that each variable can be assumed independent of other variables. Displacement, speed and angle of wave approach are considered constant for the vessel and the model in this paper. All geometrical parameters and vessel Hull Form coefficients affect the vessel hydrodynamic coefficients differently. Two of these mentioned parameters are the waterplane area coefficient and prismatic coefficient whose effects on the vessel seakeeping are studied. Simulation results indicate that present modeling can be applied to vessel Hull Form design, considering geometrical limits and the desired optimal conditions.
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an evolutionary optimization technique applied to resistance reduction of the ship Hull Form
Journal of Naval Architecture and Marine Engineering, 2013Co-Authors: Hassan Zakerdoost, Hassan Ghassemi, Mahmoud GhiasiAbstract:Hull Form optimization from a hydrodynamic perFormance point of view is an important aspect of ship design. This paper presents a computational method to estimate the ship resistance (viscous & wave) in calm-water. In the optimization process the evolution strategy (ES) technique is linked to the computational method to obtain an optimum Hull Form by taking into account the displacement as design constraint. For allowing the large variation of Hull Form during optimization process the Hull surface is represented by NURBS. New Hull Forms are obtained from the well-known S60 Hull and the classical Wigley Hull taken as initial Hulls in the optimization process at Fn=0.316 . The optimization variables are a combination of ship Hull offsets and main dimensions. The benchmark results for two test cases indicate that the total resistance of optimized Hulls is reduced significantly. DOI: http://dx.doi.org/10.3329/jname.v10i1.12927
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Ship Hull Form optimization by evolutionary algorithm in order to diminish the drag
Journal of Marine Science and Application, 2013Co-Authors: Hassan Zakerdoost, Hassan Ghassemi, Mahmoud GhiasiAbstract:This study presents a numerical method for optimizing Hull Form in calm water with respect to total drag which contains a viscous drag and a wave drag. The ITTC 1957 model-ship correlation line was used to predict frictional drag and the corrected linearized thin-ship theory was employed to estimate the wave drag. The evolution strategy (ES) which is a member of the evolutionary algorithms (EAs) family obtains an optimum Hull Form by considering some design constraints. Standard Wigley Hull is considered as an initial Hull in optimization procedures for two test cases and new Hull Forms were achieved at Froude numbers 0.24, 0.316 and 0.408. In one case the ES technique was ran for the initial Hull Form, where the main dimensions were fixed and the only variables were the Hull offsets. In the other case in addition to Hull offsets, the main dimensions were considered as variables that are optimized simultaneously. The numerical results of optimization procedure demonstrate that the optimized Hull Forms yield a reduction in total drag.
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an innovative method for parametric design of planing tunnel vessel Hull Form
Ocean Engineering, 2013Co-Authors: Morteza Ghassabzadeh, Hassan GhassemiAbstract:In this work, a new mathematical procedure has been developed to automatically generate the Hull Form of planing tunnel vessels. Due to the complex and time consuming nature of the Hull Form generation, it is vital to use a nimble and precise method in designing and optimization of Hull Form of these vessels. In the present method, the minimum number of input control parameters has been employed to design the Hull Form geometry. In the first step of modeling procedure, four longitudinal guideline functions are defined that use two different approaches, namely, polynomial functions and Non-UniForm Rational B-Spline (NURBS) curves. In the second step, using specified key points, the section curves are generated via three different models including; the parabolic, the elliptic and the NURBS curves. Then, the fair transverse sections, the fair surfaces and the solid models could be generated. In a case study, the generation of a number of Hull Forms based on three different models, implies that the method is capable of designing tunnel vessels precisely and quickly.
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Automatic generation of the planning tunnel high speed craft Hull Form
Journal of Marine Science and Application, 2012Co-Authors: Morteza Ghassabzadeh, Hassan GhassemiAbstract:The creation of geometric model of a ship to determine the characteristics of hydrostatic and hydrodynamic, and also for structural design and equipments arrangement are so important in the ship design process. Planning tunnel high speed craft is one of the crafts in which, achievement to their top speed is more important. These crafts with the use of tunnel have the aero-hydrodynamics properties to diminish the resistance, good sea-keeping behavior, reduce slamming and avoid porpoising. Because of the existence of the tunnel, the Hull Form generation of these crafts is more complex and difficult. In this paper, it has attempted to provide a method based on geometry creation guidelines and with an entry of the least control and Hull Form adjustment parameters, to generate automatically the Hull Form of planning tunnel craft. At first, the equations of mathematical model are described and subsequent, three different models generated based on present method are compared and analyzed. Obviously, the generated model has more application in the early stages of design.
Jungeun Choi - One of the best experts on this subject based on the ideXlab platform.
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bow Hull Form optimization in waves of a 66 000 dwt bulk carrier
International Journal of Naval Architecture and Ocean Engineering, 2017Co-Authors: Cheolmin Lee, Inwon Lee, Jungeun ChoiAbstract:Abstract This paper uses optimization techniques to obtain bow Hull Form of a 66,000 DWT bulk carrier in calm water and in waves. Parametric modification functions of SAC and section shape of DLWL are used for Hull Form variation. Multi-objective functions are applied to minimize the wave-making resistance in calm water and added resistance in regular head wave of λ/L = 0.5. WAVIS version 1.3 is used to obtain wave-making resistance. The modified Fujii and Takahashi's Formula is applied to obtain the added resistance in short wave. The PSO algorithm is employed for the optimization technique. The resistance and motion characteristics in calm water and regular and irregular head waves of the three Hull Forms are compared. It has been shown that the optimal brings 13.2% reduction in the wave-making resistance and 13.8% reduction in the added resistance at λ/L = 0.5; and the mean added resistance reduces by 9.5% at sea state 5.
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Hull-Form optimization using parametric modification functions and particle swarm optimization
Journal of Marine Science and Technology, 2016Co-Authors: Jungeun Choi, Hohwan ChunAbstract:The focus of this paper is on devising designer-friendly Hull-Form variations coupled with optimization algorithms. Hull-Form variations are carried out through parametric modification functions. Two kinds of representative optimization algorithms are considered here. One is the well-known sequential quadratic programming which is the derivative based. The other is particle swarm optimization which is the derivative free. The results applying these two algorithms to typical Hull-Form optimization problems are discussed in the paper. The technique using the parametric modification functions has been developed for modifying the ship’s geometry according to the widely recognized naval architect’s design practice. An original geometry can be easily deFormed through the change of the variables of the modification functions; and useful inFormation about the effect of the parameters is immediately obtained. Moreover, the variables of the modification functions can be considered as the design variables in the Formulation of the optimization problem. For the perFormance prediction of the Hull Form, WAVIS version 1.3 is used for the potential-flow and RANS solver. Computational results for both single- and multi-objective problems are presented.
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Hull Form optimization of ksuezmax to enhance resistance perFormance
International Journal of Naval Architecture and Ocean Engineering, 2015Co-Authors: Jongheon Park, Jungeun Choi, Hohwan ChunAbstract:ABSTRACT: This paper deploys optimization techniques to obtain the optimum Hull Form of KSUEZMAX at the conditions of full-load draft and design speed. The processes have been carried out using a RaPID-HOP program. The bow and the stern Hull-Forms are optimized separately without altering neither, and the resulting versions of the two are then combined. Objective functions are the minimum values of wave-making and viscous pressure resistance coefficients for the bow and stern. Parametric modification functions for the bow Hull-Form variation are SAC shape, section shape (U-Vtype, DLWL type), bulb shape (bulb height and size); and those for the stern are SAC and section shape (U-Vtype, DLWL type). WAVIS version 1.3 code is usedfor the potential and the viscous-flow solver. Prior to the optimization, a parametric study has been conducted to observe the effects of design parameters on the objective functions. SQP has been applied for the optimization algorithm. The model tests have been conducted at a towing tank to evaluate the resistance perFormance of the optimized Hull-Form. It has been noted that the optimized Hull-Form brings 2.4% and 6.8% reduction in total and residual resistance coefficients compared to those of the original Hull-Form. The propulsive efficiency increases by 2.0% and the delivered power is reduced 3.7%, whereas the propeller rotating speed increases slightly by 0.41 rpm.
