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Article type: Cover
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Cover1-
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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Article type: Appendix
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App1-
Published: March 25, 2000
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Article type: Index
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Toc1-
Published: March 25, 2000
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Article type: Index
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Published: March 25, 2000
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Mashud KARIM, Mitsuhisa IKEHATA
Article type: Article
Pages
1-9
Published: March 25, 2000
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A genetic algorithm(GA)based optimization technique is used in combination with boundary element method. Firstly, the boundary element method is applied to analyze the hydrofoil for a wide range of angles of attack, aspect ratios, and maximum camber and thickness ratios assuming that the thickness and camber distributions of hydrofoil section are given. Then the lift, drag and other parameters involved in the imposed constraints are approximated by the second-degree polynomial functions of angle of attack, aspect ratio and maximum camber and thickness ratios. The coefficients of these polynomials are solved by the method of least squares using the information provided by the boundary element analysis. The optimization algorithm then searches for an improved geometry of the hydrofoil of minimum drag satisfying all of the specified requirements.
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Shoji SHINGO, Mitsuhisa IKEHATA
Article type: Article
Pages
11-16
Published: March 25, 2000
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In this paper, the scale effect of flow field around ship is studied by the CFD simulation at model scale and full scale Reynolds numbers in towing condition. A finite-volume upwind scheme, pseud-compressibility and two turbulence models are used as the numerical method. Turbulence models are Baldwin-Lomax turbulence model and SR222 modified Baldwin-Lomax turbulence model, which are included in the category of zero equation turbulence model. Present calculation is applied to Series 60 Cb=0.6 and Ryukou-maru hull form. In conclusion, the numerical calculation can be useful tools in studying scale effect of wake distribution and resistance performance.
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Tadanori KANEKO, Makoto UCHIDA, Eiichi NISHIKAWA
Article type: Article
Pages
17-22
Published: March 25, 2000
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Performance tests of a fully submerged hydrofoil travelling near a water surface are carried out. The lift and drag forces are measured by a load cell in the towing tank of Kobe University of Mercantile Marine(KUMM). The flow characteristics around the hydrofoil are observed in both of the towing tank and the circulating water channel of KUMM. The examined hydrofoil is made by author's own hands with FRP materials. The type of wing section is NACA2410. Test variables are attack angle, immersion depth and advance speed. The immersion depth and advance speeds are varied extensively in order to examine the relation between the performance of hydrofoil and the flow characteristics in detail. The obtained results are summarized as follows. (1)In a low Froude number region, the performance of hydrofoil changes drastically. (2)In case of little immersion depth, the lift performance remarkably declines in the region of Froude number defined with immersion depth Fr-I=1.0-1.3. In the nighborhood of Fr-I=1.1, the lift takes a minimum value. (3)In this neighborhood, a wave-breaking phenomenon is observed just over the hydrofoil. The location of a wave breaking moves backward with advance speed. (3)Wadlin's estimation method is applicable in case of large immersion depth or large Fr-I. However, in the region where the water surface effects are remarkable on the hydrofoil performance, the estimation method is not applicable.
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Yoshiaki TSUKADA, Munehiko HINATSU, Yoshimasa MINAMI, Masaru TSUJIMOTO ...
Article type: Article
Pages
23-28
Published: March 25, 2000
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Ship Propulsive performance so far has been evaluated mainly in still waters. However, since ships are operated in actual seas with winds and waves, we should exert to evaluate propulsive performance in ship operating conditions. Seiun-maru, a training ship which belongs to Institute for Sea Training equips an automatic monitoring system for voyage data related on propulsive performance. This paper presents a method to evaluate a ship propulsive performance using voyage data gathering through a voyage round the world of Seiun-maru. The effects of natural forces such as winds and waves on the propulsive performance are estimated through the analyses. The reduction of propulsive performance due to natual forces is also estimated using theoretical and experimental methods. Discussions are carried out with comparing voyage and estimated data of propulsive performace.
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Hiroyoshi SUZUKI, Kiyoshige MATSUMURA
Article type: Article
Pages
29-38
Published: March 25, 2000
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An improvement method of zero-equation turbulence model was proposed. The improvement was carried out being approximated κ and ε used in the eddy viscosity expression of Shih-Lumley model to the characteristics of time-averaged velocity field like free stream velocity or displacement thickness. The method suggested a way to reduce higher-order turbulence model like an ASM(Algebraic Stress Model)to zero-equation turbulence model. CFD computations were carried out using this improved model. The model could simulate longitudinal vortices in hull ship stern flow, but the approximate method of turbulent length scale and turbulent velocity scale needed being modified.
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Ritsuo SHIGEHIRO, Takako KURODA, Akihiko MATSUDA, Sirou SUZUKI
Article type: Article
Pages
39-48
Published: March 25, 2000
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The reduction of the pitching motion of ships by mean of anti-pitching fins at the bow is analyzed both qualitatively and quantitatively through theoretical and model experimental approaches. This paper is intended to show the effect of anti-pitching fin at the stern from the viewpoint of passengers' comfort. This idea has two advantage. Firstly, the maximum force acting on the fin at the stern is smaller than that on the fin at the bow in slamming conditions. Secondly, since the fin at the stern is in wake of hull, the added resistance of fin at the stern is smaller than that of the fin at the bow. Model experiments were conducted to evaluate the effect of the anti-pitching fins on ship motions. The fin at the stern reduces vertical accelerations from 0.25G to 0.20G at the position of the bridge on the condition of a wave height of 2.0 m in head seas. Also, the authors present a new method for evaluating passenger' comfort based on questionnaires given to passenger and measured ship motions of the Kagoshima maru. The correlation coefficient between the new method and questionnaires is 0.71. We can mention that the method is reliable for estimating passengers' comfort.
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Akinori YUMURO, Takayuki TSUTSUMI, Masatomo MAEMURA
Article type: Article
Pages
49-53
Published: March 25, 2000
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This report relates to some model experiments with respect to the shallow water effect on roll damping of a ship with forward speed. The free and forced rolling tests were carried out to obtain the roll damping coefficients. These tests were conducted by employing a tanker type ship named ESSO OSAKA. The experimental results indicate that roll damping force increases with decrement of water depth regardless of the extent of the ship speed. In addition, it can be said that rate of the increase in shallow water is grater than that in deep water. Moreover, the lift component of roll damping force in shallow water was estimated from the steady characteristics of lateral forces on the ship hull. The lateral forces were determined from oblique tow tests performed at finite water depth. There is fair correspondence between the lift component and roll damping force due to forward speed. As a result, it may be concluded that in shallow water condition the lift component occupies the major portion of roll damping caused by advance speed.
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Toru KATAYAMA, Takashige HINAMI, Yoshiho IKEDA
Article type: Article
Pages
55-62
Published: March 25, 2000
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It is known that planing craft suffer significant wave load and impact force=when they run in wave at high-speed. Some peculiar violent motions for planing craft occur in severe seas. For example, jumping from wave crest and falling down to wave surface and so=on. Recently, this type of craft is widely used as a leisure boat and Froude=number of such craft is over 6.0. For such super high-speed craft, even small waves cause dangerous. However, =it has not been clarified what sea state are the limiting criteria for full=speed running. In the present study, the ship motions of such a craft at super high-speed, =that means at Fn=2.0 to 5.0, in regular head waves are measured in a=towing tank. The results shows that the motion can be divided into some different types=those are linear motion, non-linear motion with and without jumping. The criterion of each type is determined according to running conditions ; =Froude number, wave period and wave height and so on. In addition, it is studied that the existent theoretical method based on=potential theory(non-linear strip method^<4)-9))>and a proposal method, =in which some hydrodynamic forces are replaced by experimental data, apply=to estimate motions of planing craft at super high-speed to compare with=measured ones.
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Kenji YAMAKAWA, Shoichi HARA, Kunihiro HOSHINO, Kazuhiro YUKAWA, Hiros ...
Article type: Article
Pages
63-69
Published: March 25, 2000
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The occurrence of marine disasters tends to increase in recent years. In many cases, a large quantity of crude oil spilled into the sea from shipwreched tankers in addition to the damage of ship hull. These accidents strongly remind us the necessity of marine environment protection. Based on this experience, we started a project to develop a new technology to recover spilled oil effectively in the open sea. We investigated the barge type Oil Recovery Vessel(length 70m, width 24m, water depth 2.5m), which is generally operated as a multipurpose work vessel for an offshore construction, sea surface cleaning and so on. In order to provide calm water surface in a moon-pool inside a barge type Oil Recovery Vessel, the motion characteristics of the vessel and water surface elevation in the moon-pool in following and head wave have been examined with a 1 / 20 scale model ship of the Oil Recovery Vessel. The model ship consists of 3 parts ; intake, waterway, and moon-pool. In this paper, we compared the effects on the water surface elevation without or with some different kinds of attachments to provide calm water surface in the moon-pool inside the model ship. From these results, we obtained the following concluding remarks. It has been found that the rate of relative motion of water surface in the moon-pool to the incident wave height becomes 0.3〜0.4 and 0.1〜0.2 on the following wave and head wave condition respectively by equipping the Oil Recovery Vessel with these attachments.
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Shoichi HARA, Kenji YAMAKAWA, Kunihiro HOSHINO, Kazuhiro YUKAWA
Article type: Article
Pages
71-78
Published: March 25, 2000
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There were many accidents in the past causing oil leakage due to damage without the effective towing measures like 'Nakhodka' oil leakage incident. In the oil leakage incident of the tanker 'Braer' which drifted due to engine problems offshore of Scotland, the trial of settling up the towline failed resulting in the oil leakage of 95, 000 kl. Our country imports the large quantity of crude oil, liquid gas, and also transports and exports the domestic produced chemicals. Besides, sea areas are the course of crude oil transportation, so there is a frequent traffic of Japanese and foreign tankers. Moreover, sea condition around our country is very rough especially in winter. This may cause damaged, superannuated ships, or engine trouble, and those wrecked part of the ships would cause oil leakage, collision, explosion, or fire. Therefore the towline tension and unstable motion of the disabled and damaged ships have been investigated in this paper using the geometrical model ship in the towing experiment in order to establish the estimation method of the towing force and towing method.The towing experiment has been carried out both in still water and in waves. The towing resistance coefficients on various kinds of conditions such as towing direction, towing speed, ship status and towing points have been compared in still water. The unstable motion in regular waves has also been compared with that in still water concerning sway amplitude, yaw amplitude and yaw period. It is found that the unstable motion in waves is small compared with the case in still water on the condition of the towing speed less than 6 kt in full-scale. The yawing period is approximately equal to that in waves irrespective of ship status during towing. The towing resistance becomes proportional to third power of the towing speed rather than second power especially when the damaged ships are towed including mass of water inside the broken hull.
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Hiroshi ISSHIKI, Syuichi NAGATA
Article type: Article
Pages
79-86
Published: March 25, 2000
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Variational principles related to motions of an elastic plate floating on a water surface are discussed. Hamilton's principle related to motions of a plate and Kelvin's principle related to those of water are unified into Hamilton-Kelvin's principle. Hamilton-Kelvin's principle is then transformed into Hamilton-Dirichlet's principle. Some versions of the last principle are derived for applications to numerical calculations.
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Shigehiro HAYASHI, Naruyoshi IZUMI, Kentaro KIMURA
Article type: Article
Pages
87-92
Published: March 25, 2000
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ISO6954(Guidelines for the overall evaluation of vibration in merchant ship), which was adopted by ISO(International Standard Organization)in 1984, is generally used as the guideline for evaluation of vibration level in a superstructure. It is necessary to design the superstructure, in such a way, the vibration that occurs in the superstructure should satisfy the evalution curve of this guideline. In this paper, the vibration level is defined, which contains the vibration force of engine, and the optimization system for vibration level is verified by applying it to a simple approximated FE model of ship structure. In this way a more realistic system can be analised.
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Sunil MUKHERJEE, Shigehiro HAYASHI
Article type: Article
Pages
93-98
Published: March 25, 2000
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The complexity of ship structure analysis may result in a possibility that certain parts of the structure may not be optimum or may even violate the stipulated rule requirements. Carrying out a global analysis to bring these objectives under rule requirements is prohibitively expensive and time consuming also. The concept of zoom analysis can effectively be utilized to isolate these critical structural areas and then optimizing it for the required criterion could be thought of as a viable solution. Here a variational approach is given by zooming the particular region of the ship structure first and optimizing it for a particular criterion. The transverse section of a typical Bulk Carrier is taken as an example and optimization is carried out with respect to the design of maximum value of von-Mises stress over selected regions of the frame. The results show a gradual reduction of stress levels in the critical regions after the optimization through this method.
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Tetsuya YAO, Masahiko FUJIKUBO, Chikahisa MURAKAMI, Takeshi MORIGUCHI
Article type: Article
Pages
99-106
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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Web panels of girders and floors in a ship structure have many openings for piping and passing. These openings reduce the buckling strength of panels in most cases, and it is very important to estimate the influence of openings on the buckling strength of panels. From this point of view, a series of eigenvalue analyses were performed to evaluate the elastic buckling strength of perforated panels. The influence of adjacent panels without opening was also examined. It has been found that : (1)The regions with high stress and low stress are produced because of stress concentration due to opening. When buckling deflection takes place at a high stress region, buckling strength is reduced. On the other hand, it is increased when buckling deflection takes place at a low stress region. (2)When an opening in a web of a girder with horizontal stiffeners is large, high stress region is produced in the adjacent panels without opening. In this case, the buckling of adjacent panels dominates the buckling strength of the web as a whole. (3)In some cases, rule formulae of classification societies give relatively low elastic buckling strength for perforated plates compared to the results of FEM analyses.
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Hiroo OKADA, Masaharu TANAKA, Takashi TSUBOGO, Koji MASAOKA
Article type: Article
Pages
107-113
Published: March 25, 2000
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This paper deals with the dynamic response and strength of long submerged structures with tension legs in regular waves. First, a simplified estimation method is presented for dynamic responses of such a structure in regular waves using a simple beam model on an elastic foundation. Then, effects of the incident wave frequency, wave direction and the tension leg on the characteristics of the frequency response amplitude for the deflection and bending stress are numerically identified. Next, in order to demonstrate the validity of the above method, experimental studies are carried out for a basic model which is compoded of a vinyl chloride pipe as the main structure with polystyrol form blocks as buoyancy members and with tension legs(silicon rubber strings). Finally, it is found that the simplified estimation results are in good correspondence with the experimental results for the dynamic response of long submerged structures with tension legs.
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Koji MASAOKA, A.L. TALAVERA, Yasuhiro TSUKAMOTO, Hiroo OKADA
Article type: Article
Pages
115-121
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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It is important to know longitudinal strength of ship structures. Collapse of hull girder under the longitudinal bending moment is the most serious ship collapse mechanism. In this paper, ultimate longitudinal bending moment is calculated using Smith method. Stress-strain curves of rectangular plates, which are used in Smith method, are obtained from numerical database of F.E.M considering large deflection and elasto-plastic behavior. This method is applied to reliability analysis and statistical values such as standard deviations and reliability indexes are investigated by Monte Carlo simulation and sensitivity analysis. It is found from this study that the values of COVs of ultimate longitudinal bending moments are less than half of ones of yield stresses.
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Susumu MATSUNO, Setsuo IWATA, Kazuhiro YASUDA, Hiroshi TANAKA, Masakat ...
Article type: Article
Pages
123-128
Published: March 25, 2000
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Results from an experimental and FEM analysis of the composite steel concrete cylindrical shell structures of open sandwich system on ultimate strength are reported. In the experimental investigation, concentrated loading tests were conducted on open sandwich type composite cylindrical shell panels. From the experiments, it was clarified that the composite shell panel under concentrated loading showed the punching shear failure, but the composite panels exhibited the high load bearing capacity after the punching shear failure. In the FEM analysis, the deflection and stress distribution of the models were calculated.
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Kohei MATSUMOTO, Toshimasa SAITOH, Hiroshi TANO
Article type: Article
Pages
129-134
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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In vibration design of resonant avoidance to fore and aft vibration of superstructure, it is an important technology to estimate accurate natural frequency and to avoid it from resonant zone of blade or cylinder frequency in case of resonance. In this second report, authors investigated coupled vibration effect of local vibrating body such as funnel or dodger upon natural frequency of superstructure. By connecting funnel casing and deck of superstructure, natural frequency of superstructure becomes extremely high when its fundamental frequency exists higher than that of funnel. It is shown that this phenomenon can be applicable to avoid resonance in actual ship design of superstructure vibration. Long wings(dodgers)which exist at navigation bridge deck also affect the natural frequency of superstructure. Coupled vibration effect of dodger is found to lower natural frequency of superstructure.
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Yasumitsu TOMITA, Kiyoshi HASHIMOTO, Naoki OSAWA, Nobuyuki YAMAGA, Rei ...
Article type: Article
Pages
135-140
Published: March 25, 2000
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The propriety of the approximate calculation method for cyclic deformation behavior analysis proposed by Reppeto-Ortiz[Acta mater. 45, 6(1997)2577-2595]based on the constitutive model developed by Ortiz-Popov[Proc.R.Soc.Lond.A 379(1982)439-458]which emanates directly from a clear micromechanical picture is examind. It is needed to establish such calculation method in order to deepen our understanding of micromechanical aspects of PSBs formation process. As a result, it is found that Repetto's approximate method gives a good account of the nature of the relationship between shear atress range and shear strain range qualitatively and quantitatively.
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Zhengqi WU, Atsushi EMOTO, Hisashi SERIZAWA, Hidekazu MURAKAWA
Article type: Article
Pages
141-148
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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The behavior of a crack in an elastic strip under pre-stretching load is atudied using the proposed interface element. For this study, the critical pre-stretching load at which the crack becomes unstable is computed as a static problem first. Then, based on the knowledge obtained for the stability of the crack, the speed of the crack propagating in the pre-stretched plate with an initial crack at the center is clarified. Especially the influences of various factors, such as the pre-stretching, the surface energy, the bonding strength and the size of element on the crack speed under steady propagation are investigated. Through this study it is found that the behavior of the simulated crack at the onset of the instability can be divided into the stress controlled and the energy controlled types. When the surface energy is small, the scale parameter of the interface potential is large and the mesh size is sufficiently small the behavior of the crack becomes the energy controlled type. In case of the energy controlled type the speed of the crack under steady state is determined only by the surface energy. The influence of the bonding strength and the mesh division is small. As for the pre-stretching, the crack speed increases with the pre-stretching and it converges to Layleigh wave speed.
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Masakazu SHIBAHARA, Hisashi SERIZAWA, Hidekazu MURAKAWA, Zengqi WU
Article type: Article
Pages
149-155
Published: March 25, 2000
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In the previous report, a finite element method(FEM)using temperature dependent interface element is proposed for the occurrence and propagation of hot cracking under welding. The appropriateness of proposed method is investigated, and it is found that the computed results agree with the phenomena generally observed in experiments. In this report, the potential usefulness of the proposed method for clarifying the mechanism of hot cracking is demonstrated using the Fish Bone type hot cracking test. There are two types of Fish Bone test depending on the choice of the welding direction. In case of the originally proposed test, the welding starts from the wider side. The test with welding in the opposite direction is also commonly employed. But clear deference between the two methods is not given. After brief discussion on the analysis of Fish Bone test, the acceptability of the computed results by the proposed method is closely examined. Especially, effects of the BTR(Brittleness Temperature Range), the strength ratio between yield stress σ_Y and interfacial bonding strength in BTR σ_<cr>, the scale parameter γ_0 involved in the interface potential @φ@ and the size of the mesh are investigated. Through this study, it is found that the hot cracking simulated by the proposed method is basically determined by the BTR and the scale parameter γ_0. This agrees with the concept proposed by Matsuda through high temperature ductility curve. Finally, the possible procedure to determine these parameters used in the proposed method is discussed.
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Yasushi HIGO
Article type: Article
Pages
157-160
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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When the seaquake acting on a floating structure is discussed, the effect of free-surface waves is usually ignored. However, when sea-bed vibrates due to earthquake, the compressional waves ; i.e.the sound waves ; in sea water and the water waves on the free-surface occure at the same time. If the interaction between both waves may exist, the combined theory of the sound and water waves should be considered. This paper gives the investigating results of the interaction between free-surface waves and underwater sound waves in frequency domain.
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Yasushi HIGO
Article type: Article
Pages
161-165
Published: March 25, 2000
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This paper gives the fundamental equation of underwater sound propagation. When the problem such as seaquake is solved in time domain, the interaction between free-surface waves and underwater sound waves should be considered. We have to use the governing equation of the underwater sound propagation on the fields with gravity effect at that time. In this paper, the equation that governs the sound propagation is derived based on the combined theory of sound and gravity waves. Then the final governing equation of sound propagation in the water with gravity effect is expressed by means of the formula of thermodynamics.
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Nobuhiro BABA, Ken-ichi KITAURA, Kazuyoshi YAMAMOTO, Kosuke ARAI
Article type: Article
Pages
167-172
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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The mixing of stratified fluid through horizontal circulation in the ocean=is investigated in the laboratory. The circulation is generated by a=rotating vertical cylinder in the stratified fluid in a cylindrical cavity=in the visualization experiments. The deepening of a mixed layer into a=stratified fluid with linear density gradient is observed by the=shadowgraph method. The density profiles are measured with a conductivity=probe to examine the characteristic of the density interface in the=cylindrical cavity. The mixing occurs soon after the start of the experiment by the=three-dimensional motion around the rotating cylinder. The density=interface is formed beneath the end of the circular cylinder by erosion of=the basic density and the larger-scale horizontal circulation develops to=enforce the mixing across the pycnocline by the vertical shear as well as=the three-dimensional motion peculiar to the circulation. It is found that=in the mixed layer the vorticity concentration leads to the generation of=the vortex core in which the upwelling pumps up the dense fluid across the=interface.
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Takayuki KASHIMA, Nobuhiro BABA, Ken-icni KITAURA
Article type: Article
Pages
173-178
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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This paper describes experiments on the mixing of stratified fluid by=surface cooling. A small tank is filled with water with a constant=temperature gradient in depth and cooled at the top copper plate by=circulating cool water of a constant temperature. The two-dimensional=primary flow is visualized using fluorescence dye and analysed by the=digital image processing. The temperature fluctuation is measured using a=platinum resistance wire. Soon after the cooling starts, a thin layer beneath the cooled top plate=becomes unstable so as to make periodic lateral fluctuation visible. The=periodic mass concentration due to this instability leads to the formation=of regular flow structure with a raw of drops of dense water. While=falling down, these drops grow into blobs by entrainment of ambient fluid. =It is confirmed that although the interaction of the blobs with each other=such as coalescence, merging and absorption seems to be chaotic, the depth=of the mixed layer increases at the rate proportional to the root of time. =These experimental results are consistent with the computational results of=the two-dimensional flow structure reported in the preceding paper. It is=concluded that the two-dimensional features of the mixing by surface=cooling are simulated in a successful manner in the experiment and in the=computation.
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Hidemitsu YAMADA, Kazuhiko HASEGAWA, Tetsunori YAMASHITA
Article type: Article
Pages
179-186
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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This paper describes the optimal weather adjustment using Kalman filter with wave estimator. During ocean going, vessels are always affected by external disturbances such as winds and waves, especially waves strongly affect vessel's yawing motion. From the beginning, vessel's autopilots have the facilities which reduce yawing motion induced by wave as much as possible, and this is called weather adjustment mechanism. There are many types of weather adjustments. Most popular types are simple nonlinear elements, but these types have not performed enough as might be expected. Several studies were done applying Kalman filter as weather adjustment, but wave effects were considered as white noise in system equations. Tanaka et al.proposed Kalman filter with wave estimator, and they called "optimal weather adjustment". The purpose of this paper is to confirm the effectiveness of "optimal weather adjustment" applying to the sea trials. Furthermore we have considered wind effect and proposed a new method to identify the parameters of wave and wind estimators. This optimal weather adjustment shows much more performance to reduce rudder movement than conventional weather adjustment.
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Tatsuo NISHIKAWA, Koji MASAOKA, Yusuke TAHARA, Yoji HIMENO
Article type: Article
Pages
187-197
Published: March 25, 2000
Released on J-STAGE: April 01, 2018
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This paper presents a numerical analysis on unsteady aeroelastic problem for half cylinder membrane structure in onset viscous flow. For the flow field, the unsteady incompressible 2D Navier-Stokes(NS)and continuity equations are solved by a time marching numerical scheme. A Finite-Element Method(FEM)considering large deflection with membrane finite element is used to estimate the elastic characteristics of the membrane. The dynamic equations are solved by Newmark β method. At first, the kernels of these numerical methods are developed and verified, and an overview is given of the present numerical approach. The computational results are presented and discussed for a half cylinder membrane structure. The vortex-induced vibration is most essential in the present study, and in this paper the computation has been successfully implemented about a=basic model which induces large deflection and vibrations by wind force.
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Article type: Appendix
Pages
App2-
Published: March 25, 2000
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Article type: Cover
Pages
Cover2-
Published: March 25, 2000
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