著者

土井 康明 上田 隆浩 茂里 一紘 二宮 伸治

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.186, pp.89-96, 1999-12

被引用文献数

3 2

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A numerical simulation method of the motion of a rowing race boat is developed in order to evaluate the performance of oar size and rowing pattern. The driving force of blade is measured experimentally. The resistance of the boat is referred to the experimental result carried out in a towing tank. The motion of crew, which is most important in the simulation, is evaluated from the equation of a boat motion where the other terms are experimentally measured. These measured external forces are modeled by Fourier series or polynominal expressions. The equation of a boat motion is numerically solved by use of Runge-Kutta method. The Simulated boat velocity and force acting on blade are compared with the measured ones. The experiment was carried out in cooperation with the crew at Hiroshima University. Good agreement with the simulated results and measured ones shows that the present simulation method has merit to evaluate the rowing performance. Through the present simulation method, outboard length, blade area, stroke rage and phase of catch are evaluated.

著者

岡村 尚昭

出版者

The Japan Society of Naval Architects and Ocean Engineers

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

vol.1975, no.138, pp.118-127, 1975 (Released:2009-09-04)

参考文献数

18

被引用文献数

1 1

---

This paper is concerned with the development of a method for calculating the hydrodynamic characteristics of marine propellers in a viscous fluid.Firstly, the characteristics in a non-viscous fluid are calculated by applying the propeller lifting surface theory and at each propeller section, a so-called corresponding two-dimensional wing which has the same hydrodynamic property and geometrical thickness distribution as the corresponding propeller section, is derived from the calculated circulation distribution. Then circulations corrected by the effects of viscosity and drag coefficients of propeller sections are obtained by using calculated boundary layer properties of the corresponding two-dimensional wings. Finally, the propeller characteristics in a viscous fluid can be obtained from these circulations and drag coefficients.Calculated results of propeller performances are compared with open-water test results and agreement between calculation and experiment is good. Also scale effects of propeller performance are examined by this method.

著者

高田 憲尚

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.190, pp.13-25, 2001-12

被引用文献数

3 1

---

The incompressible Reynolds Averaged Navier-Stokes (RANS) code using the multi-block grid method has been developed for simulating the steady free suface flows over ship having complex geometries. "Horizontal Mode","Vertical Mode"and"BJ-SGS" which are methods of updating boundary conditions on block interfaces are incorporated in the present code and investigated in the computation of free surface flows about Wigley hull. The new code is applied to computation of transom stern flow about a container ship and a high speed vessel and those numerical results are compared with the experimental results.

著者

児玉 良明

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.172, pp.147-155, 1992-12

被引用文献数

16 6

---

A globally conservative NS solver for flow past a ship hull has been developed. It uses a 3rd-order accurate upwind differencing of the preprocessing (MUSCL) type for inviscid terms, in which the non -uniformity of grid spacing is taken into account. Using the solver, the drag of a fiat plate at zero incidence was computed in the Reynolds number range R_e=4.0 × 10^5 to R_e=4.0 × 10^7. The dependence of the drag on the degree of clustering of grid points was checked. The computed drag agreed with the Schoenherr value within 4%. An appropriate criterion for the minimum grid spacing Δ_<min> adjacent to solid wall with this particular scheme seems to be Δ_<min>=0.005/√<R_e>. Then the drag of the Series 60 (C_B=0.6) ship hull with the double model assumption was computed in the same Reynolds number range using grids with various Δ_<min> and various degree of clustering toward bow and stem. Although the computed drag values showed some scattering among different grids, the results with the smallest Δ_<min> agreed well with the measured values throughout the Reynolds number range.

著者

岸 進 宇都 正太郎 加納 敏幸 上園 政裕 川島 義伸 泉山 耕

出版者

The Japan Society of Naval Architects and Ocean Engineers

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

vol.1996, no.180, pp.99-111, 1996 (Released:2009-09-16)

参考文献数

19

---

The patrol icebreaker “TESHIO” was built and delivered to the Japan Maritime Safety Agency in Autumn 1995. Full-scale trials in ice were conducted at the Sea of Okhotsk in February, 1996. Several kinds of test were performed in order to confirm her performance such as continuous ice-breaking, ramming and stopping performance, turning capability and zigzag course manoeuvrability, and coordinated ice-breaking operation together with the patrol icebreaker “SOYA”.While her design and construction were in process, series of model test were carried out both in ice and in ice-free water as the joint research project between Ship Research Institute, Ministry of Transport and NKK Corporation. At the ice model basins of the two organizations, comprehensive model tests in ice were conducted which included resistance and self-propulsion tests in various ice conditions, ramming and turning tests in level ice.This paper describes the results of model and full-scale tests of “TESHIO” and their correlation for both continuous ice-breaking and ramming performance.In order to predict the required BHP for the continuous ice-breaking in level ice, the propulsion coefficient was decomposed into three parts which denote effects of open water characteristics, overload and propulsor/ice interaction, respectively. The thrust deduction coefficient obtained from towed propulsion tests in ice showed very good agreement with that from overload tests in ice-free water. The predicted BHP showed good agreement with the full-scale results when the effect of propulsor/ice interaction was taken into consideration.A prediction formula for ramming penetration distance was devised using an energy-based method. Correlation of both the model and full scale data to the prediction results showed that thrust loss due to the propulsor/ice interaction and the automatic overload protection control of the main engine had much influence on the prediction of ramming performance.

著者

加藤 洋治 山口 一 岡田 真三 菊池 浩平 宮永 大

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.150, pp.140-147, 1981-12

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It is well-known that sheet cavitation inception is dependent on laminar separation. There-fore, the sheet cavitation might be controlled by restraining the separation. Authors tried to control sheet cavitation on an axisymmetric body by water jet injection, and proved experimentally that it was possible to suppress the sheet cavity. The nondimensional injection flow rate for the cavity suppression depended only on Reynolds number. The leading edge of the sheet cavity coincided with separation point which was visualized by oil film method. By increasing injection rate the reattachment point of separation bubble moved upstream and finally the separation bubble vanished. The sheet cavitation also vanished at the same condition.

著者

石井 規夫 井手 敏治

出版者

日本造船学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.160, pp.54-65, 1986

被引用文献数

2 1

---

In recent years, a highly advanced lifting surface method with high accuracy has been required in order to design the various types of propellers which demand high efficiency and to reduce ship vibration and noise. In this paper, an improved lifting surface procedure based on the vortex lattice method is presented. For the determination of a trailing vortex wake geometory, a numerical iterative procedure is described. The numerical results on propeller slipstream give a good agreement with the measured values by laser doppler velocimeter. The present method is applied to calculate the open water characteristics of a propeller. And a quasi-steady technique based on the present method is adopted to calculate the fluctuation of propeller forces and cavitation patterns behind the ship's wake field. The advantages of the present method are shown by comparing the numerical results with the experimental data of conventional and highly skewed propeller.

著者

小野 志郎 大森 英行 中川 寛之 岩崎 徹 山賀 秀夫 小澤 宏臣

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.190, pp.295-303, 2001-12

被引用文献数

1

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ナホトカ級の油流出事故を想定した高粘度、高波浪対応の油回収装置の開発に着手し、平成9年度の技術調査を踏まえて平成10年度から2年間に亘る要素研究開発を実施した。それら要素技術開発の結果に基づき、全口径型ジェットポンプを中心に油回収装置の小型、軽量化及び高効率化を図り、プロトタイプの実機1/2相当の大型模型を用いて海上災害防止センター横須賀研修所における高粘度油を用いた大掛かりな波浪中高粘度油吸引実験を実施することができた。その結果、本回収機は実海域において所期の性能を発揮できることが確認され、荒天下の高粘度油回収作業において有効な機材であることが実証された。さらに、総合的な船上処理装置の設計が可能となったことで、高波浪下 (最大波高6m) で高粘度油 (10万cSt以上) を多量 (300m<SUP>3</SUP>/h) に回収することが可能な高性能油回収装置の実用化の段階に至った。<BR>本研究の成果は研究で終わるものではなく、出来るだけ早く実機を供給し、油流出による海洋汚染の防除体制の一端を担うことによって、真の貢献が評価されるものと確信している。

著者

山内 重樹 手塚 研治

出版者

The Japan Society of Naval Architects and Ocean Engineers

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

vol.1995, no.178, pp.707-712, 1995 (Released:2009-09-04)

参考文献数

4

被引用文献数

1 6

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Nesting in shipbuilding is work that complicated parts of various sizes are arranged in steel plate as many as possible. The work has been done by experts. We have developed the automatic nesting system by use of Genetic Algorithm (GA) and new algorithm which are introduced from heuristic rules which the experts have. We call the algorithm “geometrical simplification of parts”, “pairing algorithm” and “grouping algorithm”. This paper describes that the combination with GA and new algorithm which we propose is effective to the processing speed of the system and the scrap ratio of nesting and that the system is available for practical use.

著者

平山 次清 崔 龍虎

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.189, pp.39-46, 2001-06

参考文献数

29

被引用文献数

4 1

---

The sea trials for new ships are carried out for guaranteeing the ship performances in still water. Of course, this does not guarantee the performances in operating sea condition. But the ships mostly operate in winds, waves and currents and not in still water. Usually, those effects are included in the so called sea-margin. Following to the development of sea-keeping theory and motion/wave measurement technology, the increasing demand for guaranteeing the ship performances in operating condition is natural. In this context, the establishment of the "rough sea state" will be useful as one step for realizing the guarantee in operating condition. The "rough sea state" is one of the evaluation-sea-states. Evaluation-sea-states are used as key condition that the evaluations of ship performances are carried out comparing with the monitored actual results. In this paper, we proposed such a "rough sea state" based on added wave resistance and long-term wave database constructed by hind-cast technique.

著者

綾 威雄 浅井 孝悦 為広 正起 武隈 克義 古林 義弘

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.187, pp.412-413, 2000-06

著者

田中 進 貴島 勝郎

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.174, pp.357-363, 1993-12

被引用文献数

3 1

---

It is of importance to evaluate the ship manoeuvring motion, such as the berthing in a harbour, the drifting behaviour of a disabled ship. A significant part of the lateral hydrodynamic forces acting on a ship will be due to cross flow drag, as the ship's drift velocity becomes relatively larger compared to the ahead speed. For the prediction of ship manoeuvrability at larger drifting angles, it will be required to estimate the cross flow forces accurately. In this paper, a calculation is given to the longitudinal distribution of the cross flow drag coefficient over the length of ship moving transversely. The theoretical method on basis of vortex model developed by the authors is applied to the Wigley hull and a container ship hull. By comparing with the measured results of captive model tests, the prediction results agree well with model tests. Therefore, this method will be useful for practical prediction of cross flow forces acting on a ship moving laterally, taking into account the forms of the ship's cross sections.

著者

鈴木 和夫 伊岡森 信臣

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.185, pp.9-19, 1999-06

被引用文献数

12 13

---

In the original Rankine source method suggested by Dawson, free surface panels are arranged by means of the stream line tracing method based on the double model flow. In the present study, however, it is replaced by an elliptical type panel arrangement. In order to satisfy the radiation condition on the free surface, the upstream difference operators are introduced in computational domain corresponding to those panels. By employment of this new type free surface panels, more accurate results can be obtained for a practical hull form, because it becomes very easy to increase the density of panels in near field of the ship. According to this improved Rankin source method, a hull form improvement problem to minimize the wave making resistance is discussed, in which the optimization is carried out, under the prescribed design constraints by means of the nonlinear programming technique. In the optimization process, a weight function is introduced to represent an improved hull surface, which can generate a new smooth hull surface by multiplying it to the offset data of the initial hull surface. Design parameters expressing this weight function can be determined from the optimization process based on the nonlinear programming technique. In this paper, SQP (Sequential Quadratic Programming) is employed as the nonlinear programming. As an example of the hull form improvement, the HTC (Hamburg Test Case) container ship is selected as the initial hull form to be improved.

著者

日野 孝則

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.166, 1989-12

著者

安藤 英幸 大和 裕幸 堀 晃 増田 宏 白山 晋

出版者

公益社団法人日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

no.192, pp.475-483, 2002-12

被引用文献数

1

---

Machinery maintenance activities should be based on statistics and knowledge of past machinery failures, but it is often difficult to keep gathering those data in engineers' daily works. This paper describes an approach to acquire those data and knowledge from machinery failure reports, which are written as free texts, by applying text mining techniques. The method consists of three stages. The first state is event extraction. The term event represents a status of an object ; "damage of a piston ring" is an example of it. Each machinery failure reports is converted into a set of events in this stage. The second stage is to find relations between the events. To find taxonomic relations, we defined a lexical distance and direction measure to evaluate similarities among events. To find non-taxonomical relations, an association rule mining method is used. The third stage is evaluating extracted relations. Authors tested the proposing knowledge acquisition process with 136 machinery failure reports and expert engineers validated more than 80% relations are correct knowledge.