著者
安川 宏紀
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.1999, no.186, pp.1-6, 1999 (Released:2009-09-04)
参考文献数
11

A hull form improvement method is presented using Genetic Algorithm in conjunction with Rankine source method based on a wave resistance theory for modified hull. By means of the present method, improvement of fore ship form is introduced for Series 60 (Cb =0.6) hull. As a result, the wave resistance is reduced about 25% at Fn=0.3 by modifying the original form to bulb-like bow shape. We found that GA improves the estimation accuracy of the optimum hull form.
著者
安川 宏紀 宮沢 多
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.2001, no.190, pp.181-190, 2001 (Released:2009-09-04)
参考文献数
4
被引用文献数
1

試験は, プロペラの回転方向として, 内回りと外回りの2つについて実施し比較した。試験結果をまとめると次の通りである。1. 内回りプロペラにおいては, 船尾が岸壁から離れ難く, 横移動が不能となる場合もある。外回りプロペラにおいては, 横力が明らかに大きいようであり, 船尾が岸壁から離れ易い。横移動が不能となることはない。2. プロペラ回転数の組み合わせをDS/S, S/Hと変化させても, 内回りプロペラ装備船の離岸性能の改善効果はほとんど見られない。同様に, 右舷舵角を0, ±35degと3種類変更させても, 離岸性能改善に大きな効果はない。3. 船の初期位置を岸壁からは離れたところに持ってくると, 横移動は容易となる。Fig.4に横移動試験結果の1例を示す。船影は10sec毎の右から左に動く模型船の位置を表している。内回りプロペラ (Inward) においては船がほとんど横に移動していないこと, 外回りプロペラ (Outward) においては所期の通り船尾が岸壁から離れた後で横方向へ移動していることが分かる。
著者
安川 宏紀 平田 法隆 浮田 寛之
出版者
公益社団法人 日本船舶海洋工学会
雑誌
日本船舶海洋工学会論文集 (ISSN:18803717)
巻号頁・発行日
vol.17, pp.49-56, 2013 (Released:2014-01-17)
参考文献数
9

This paper presents a practical simulation model for ship launching taking the dynamic coupling effect of trim angle change and vertical motion into account. The motion equations were derived in three stages of sliding, lift by stern and afloat modes in launching. By solving the motion equations in three stages continuously, ship speed change, trim angle change, traveling distance, pivoting load, etc. during launching can be calculated. To obtain the validation data of the simulation method, a fullscale test was carried out to measure the ship motions during launching by a Kinematic GPS (KGPS) system. Then, three antennas for KGPS were arranged on a Chip Carrier with 191.5 m in ship length. Some parameters needed for the simulation were determined by comparing with the fullscale test result. The present simulation method is useful for capturing th ship launching behavior.
著者
寺田 大介 安川 宏紀 芳村 康男 松田 真司
出版者
公益社団法人 日本船舶海洋工学会
雑誌
日本船舶海洋工学会論文集 (ISSN:18803717)
巻号頁・発行日
vol.30, pp.49-57, 2019

<p>A roll response model during maneuvering, which can express a transient motion after steering, is proposed. The transient motion, namely the transition process from initial inward heel to outward heel, is used in the rudder–roll stabilization system. Nowadays, the model reference control is well used as an autopilot system of the actual ship. As to the model, the yaw response model such as the K–T model proposed by Nomoto is used because of the convenient adjustment of parameters. However, there is not the roll response model to be able to use for the rudder–roll stabilization. In this study, the 4th order roll response model proposed by Yasukawa and Yoshimura which was obtained from the 4 degrees of freedom (surge-swayroll- yaw) mathematical maneuvering model is focused on. And it is called as the Y–Y model in this study. Firstly, assume that the change of the rolling against steering is gradual, the Y–Y model is approximated by the 2nd order. Moreover, the modeling is done by considering the fact that the rolling due to steering is a non–minimum phase system. In order to verify the effectiveness of the proposed model, the numerical experiments were carried out. The KCS container ship was selected as the sample, since there is the information of maneuvering derivatives, which was obtained by the captive model experiments, including the effect of rolling. As the result, it can be confirmed that the proposed model can be expressed rolling in the transient situation after steering well under the assumption used in the modeling of Y–Y model. Furthermore, the procedure to estimate the parameters is also proposed by using the measured onboard monitoring data, and the effectiveness is confirmed based on the numerical experiment.</p>
著者
安川 宏紀 中村 暢昭
出版者
公益社団法人 日本船舶海洋工学会
雑誌
日本船舶海洋工学会論文集 = Journal of the Japan Society of Naval Architects and Ocean Engineers (ISSN:18803717)
巻号頁・発行日
no.6, pp.313-321, 2007-12-01
参考文献数
14
被引用文献数
3 1

An analysis method is presented to know whether a towed ship is stable or not in the course stability in wind. The method is based on the linearized motion equations newly derived in this paper for the towed ship. The special feature is to take the effect of hull steady condition of the towed ship in wind into account. By means of the analysis method, the wind effects on the course stability of a towed barge were investigated. The course stability recovers in the range from beam to quartering wind even if the towed barge is unstable in no wind case. Namely, the barge is stably towed with keeping the certain heading/drift angle in the beam/quartering wind. On the contrary, the course stability reduces in head and following winds with higher speed even if the towed barge is stable. We found that the course stability of the towed ship is much affected by the hull steady condition in wind. The analysis results agreed well with the simulation results by a nonlinear time domain method. The present analysis method is useful for better understanding of the course stability of the towed ship in wind.
著者
安川 宏紀 平田 法隆 中村 陽昭 松本 之良
出版者
公益社団法人日本船舶海洋工学会
雑誌
日本船舶海洋工学会論文集 (ISSN:18803717)
巻号頁・発行日
no.4, pp.137-146, 2006-12
被引用文献数
6

A simulation method for the maneuvering motion of a towed ship in still water is presented. A 2D lumped mass method is employed for expressing the dynamics of the towing cable. The motion equations of the towed ship and the cable are derived under the assumption that the motions are defined in the horizontal plane. Motion of a towing ship is assumed to be given. As a calculation example, a towing barge with/without skegs is selected. The captive model test is carried out to capture the hydrodynamic force characteristics of the barge. Using the force characteristics, simulations are made for various towing speeds, towing cable lengths and so on. The calculated results are compared with the model test results conducted in the towing tank. The results of the slewing motion frequency, changes of heading angle and yaw rate in time domain agree well with the experiments. The present method is useful for predicting the slewing motion of towed ship.