-
Article type: Cover
Pages
Cover1-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Cover
Pages
Cover2-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
App1-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
App2-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
App3-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
App4-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
App5-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
App6-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Mitsuo KISHI, Katashi TAGUCHI, Yoshisada MUROTSU
Article type: Article
Pages
1-12
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
There are many studies on statistics of marine accidents and analyses of individual ones. However, there are few papers which were made based on systems point of view. Consequently, in this paper, systematic analyses to fires in ships are carried out by applying fault tree analysis (FTA), which is a useful tool of systems engineering. From the results of the analysis, recommendations are provided to improve the structure and equipments of machinery rooms for preventing fires in relation to marine laws and regulations. A drastic measure is to set up an effective overflow pipe to fuel oil service tank, which is obligated only by N.K. rule. Finally it is shown that FTA is applicable not only to systematic analysis of marine accidents but also to safety and reliability analysis of ships.
View full abstract
-
Noriyuki TAKASUGI, Takuya TANIUCHI, Masahiko SADA, Akihiko KAMEI, Hide ...
Article type: Article
Pages
13-19
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
Syntactic foam, consisting of hollow glass microballoons and epoxy resin, has been used as the principle buoyancy materials in recently developed deep submersibles. So, the authers developed the syntactic foam of non sorting microballoons and standard resin from 1969 to 1972. The foams specific gravity is 0.63 and the collapse pressure is more than 1,200 kgf/cm^2. The present studies were aimed at exploring special means of achieving a lighter and high-strength foam for 6,000m submersible in near future. As the result, the effect of microballoon size and packing factor on foam performance, and the relation between foam collapst pressure and uniaxial compressive modulus of epoxy resin were confirmed. Furthermore, we have succeeded in development of the high-performance syntactic foam, the specific gravity is from 0.53 to 0.56 and the collapse pressure is approximately l,200 kgf/cm^2, the same as U.S. Navy developed in 1980.
View full abstract
-
Tamaji IKEDA, Morihiko INOKUMA, Masaru NISHIYAMA, Katsuji OKUMURA
Article type: Article
Pages
21-28
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
A utility bilateral manipulator has been developed for deep submergence remotelly controlled vehicle. This manipulator can lift 45 kgf at maximum outreach of l.8 meters, and has six joints and a terminal device. All of the joints and device are given bilateral function. The symmetrical bilateral servo control system is adopted in this manipulator system. They must perform the following developments to get a high-performance manipulator. i.e. (1)low friction hydraulic actuators for slave arm and master arm, (2)small electrohydraulic servo system with precise pressure control characteristic, (3)oil immersed electoronic controller. So that, this manipulator will be able to be cotrolled in deep sea free from ambient pressure, and has good manoeuvrability by remote control. Any operator can control this manipulator freely, speedily, precisely, can perform underwater works such as bolt-nut fastening, handle rotating etc. by this manipulator.
View full abstract
-
Kohei MATSUMOTO, Mitsuru MIZUUCHI, Toshimasa SAITOH
Article type: Article
Pages
29-38
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
In order to prevent the damage of sterntube bearing due to misalignment, it is necessary to clarify the dynamic behavior of propeller shafting system. The shaft is bent by heavy propeller, action of dynamical propeller force and deformation of double bottom, and affects consequentially the sterntube bearing. This paper presents a theoretical analysis of sterntube bearing under a misaligned shaft. The relation between misalignment condition and performance of sterntube bearing has been investigated quantitatively.
View full abstract
-
Shoichi NAKAMURA, Shigeru NAITO, Keizo KOGANEYA
Article type: Article
Pages
39-44
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
In order to extract the wave power by a floating type wave absorber, an external mechanical system is necessary. In this study, a small DC-generator and a coil spring are used to control the motion of floating body. By changing the electric resistance and the spring constant of coil, arbitrary external forces can be added to the body. The sectional form of the floating body is determined by the theoretical calculation which satisfies the condition of being wave-free on one side under heave mode oscillation. To investigate the hydrodynamic properties of 2-dimensional models of wave absorber with external forces or without them, the following experiments are carried out at the small water tank which was newly built in Osaka University. (1) Measurements of added mass and damping coefficients and radiated waves by forced heave oscillation tests in still water without external forces. (2) Measurements of wave exciting forces, transmitted waves and drifting forces with restrained models in regular waves. (3) Measurements of heave motions, transmitted waves and drifting forces with heave free models in regular waves without external forces. (4) The same measurements as (3) with external forces. The results of experiments are compared with the theoretical calculations by the method of singularity distribution.
View full abstract
-
Osamu YAMAMOTO
Article type: Article
Pages
45-49
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
Complete wave power absorption is studied by using a single energy absorbing mechanism and a two-dimensional floating body of symmetrical section. The energy absorbing mechanism and the floating body are articulated at a point away from the center line of the body. The energy absorbing mechanism is activated by the heaving motion of the articulate joint and absorbs incident wave power. The floating body can movein heaving and rolling, while the swaying motion at the joint is restricted. Concerning the device mentioned above, the conditions, which the characteristics of the energy absorbing mechanism and the floating body should satisfy for complete wave power absorption, are derived theoretically. Furthermore, a model test on wave power absorption is carriod out and the result of the test shows that complete wave power absorition is possible by using a single energy absorbing mechanism and a two-dimensional floating body of symmetrical section.
View full abstract
-
Yutaka TERAO
Article type: Article
Pages
51-54
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
Potential theory always gives a mean wave force acting on the ship or floating structure only in the direction of wave propagation and they actually drift with waves. The report represents the results of a model test which moves toward the waves by itself without any propelling power or control systems. This is a wave devouring propulsion model which converts the wave energy to the thrust and drives itself if any in the direction opposite to wave propagation. The model consists of the deck, wings (fore and aft) and side plates. Side plates support the deck and wings like a figure of "H". The upper deck surface coincides with the water surface. If the model situated in the waves, on the upper deck surface wave breaking occurs and momentum flux is induced in the incident waves and transmitted waves, so it makes thrust to the waves. Moreover a wing moving forward locating in the oncoming waves, wave orbital velocity acts such as perturbation velocity to the wing and generates the thrust. From tank test, it is shown that the speed of this model toward the waves amounts to 24 cm/sec. under some condition. By the model length Froude number, this speed is correspond to Fn=0.129.
View full abstract
-
Yusaku KYOZUKA, Jun OBOKATA
Article type: Article
Pages
55-62
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
Hydrodynamic influences to a floating body by a temporal bottom (false-bottm) which is used to simulate the shallow water condition in experimental tank is studied. The numerical method is bassed on potential theory and the velocity potential is represented by the distribution of sources and dipoles over the floating body and the false-bottom. The added mass and damping coefficients of the floating body above various false-bottoms in size and shape are compared and discussed in both calculations and experiments. It is found that the interaction between the floating body and the false-bottom is significant especially at low frequency range of the oscillations and is caused mainly by reflected waves at ends of the false-bottom. Some considerations and proposals on a desirable shape of the false-bottom are discussed to realize appropriate shallow water condition.
View full abstract
-
Masamitsu ITO, Shosaburo YAMASAKI, Michio TAKAHASHI
Article type: Article
Pages
63-72
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
Recent days, owing to get better propulsive efficiency the number of propeller revolutions decrease considerably. However, it arises increasing stopping time in crash astern maneuver. Present paper deals with the crash astern performance of CPP (Controllable Pitch Propeller) and FPP (Fixed Pitch Prope11er). The model ship used is SR174B4 (Panamax type bulk carrier) and it has the propeller with large diameter and low rotation. Crash astern performance of SR174B4 equipped with FPP was studied by SR174 committee. Authors carried out the self propulsive tests of SR174B4 with CPP varying propeller loading and got the self propulsion factors. With the factors, and with the quasi-steady treatment, the stopping ability of real ship was estimated. The astern thrust of CPP and FPP alone is about the same. Concerning to required time of stopping, the case equipping a CPP is less than the case equipping a FPP in full load condition, but it reverses in ballasted load condition because of air drawing. It should be remember from the results that the stern draft in ballasted load condition of ships equipped with CPP must keep sufficient to prevent air drawing. The most important factor to affect the stopping ability is the maximum reverse pitch angle in the case of CPP and the maximum number of reverse revolutions in the case of FPP.
View full abstract
-
Takamune KITAZAWA, Masami HIKINO, Tomeo FUJIMOTO, Kohei UEDA
Article type: Article
Pages
73-78
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
By installing a nozzle just in front of a propeller, the propulsive efficiency and other performance of a ship can be improved. In this paper, effects of the nozzle are discussed by the use of experimental results and theoretical calculations. The effect of the nozzle on the propulsive efficiency is firstly illustrated with results of the propeller load test conducted by making use of an axi-symmetrical body. Secondly, nozzle's effects ascertained in towing tank tests of a ship model are shown. A theoretical calculation is applied in order to investigate into hydrodynamical characteristics of the nozzle in the non-uniform flow behind the ship model. Thirdly, sea trial results of actual ships, which confirm the effectiveness of the nozzle, are described. Other effects of the nozzle are lastly shown. The cavitation of a propeller is reduced and the maneuverability of a ship is improved by the nozzle.
View full abstract
-
Shiro MATSUI, Michihito OGURA
Article type: Article
Pages
79-84
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
In improvement or development of ship form a circulating water channel is very useful. Sometimes development plan that consists of several ship form is contrived. And these ship forms are tested by small models in a circulating water channel. Best one will be selected by qualitative comparison of test results. In this procedure it may be thought to be very important that course stability is checked at this stage. In a circulating water channel oblique towing test is easy to be carried out. Thus the authors present a method to discriminate course stability by oblique towing test results. This method is based on many hydrodynamic derivatives presented by many researchers. According to this method course stability is roughly estimated by center of lateral force when ship is sailing obliquely and fullness Cb/(L/B). Discrimination procedure and some examples applied this method are shown.
View full abstract
-
Matao TAKAGI, Kimio SAITO
Article type: Article
Pages
85-93
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
Concerning the study of non-harmonic wave problems, the hydrodynamic responses, memory effect functions, generated by an impulse in oscillating velocity of a body are required. In the previous paper, the authors discussed a calculation method for memory effect functions of a two-dimensional body. A rational calculation method for the asymptotic values of the damping coefficient in the high frequency range was shown and the memory effect functions were evaluated from the calculation in the frequency domain. In this paper, the same problem of a three-dimensional body is discussed. Firstly, the memory effect functions for a ship-like body are evaluated by use of the strip method. Secondly, the asymptotic value of the damping coefficients in the high frequency range for forced heaving and swaying hemisphere are presented by extending the Hermans method and memory effect functions are obtained by the same procedure mentioned in the previous paper. Comparisons between the results obtained from the Fourier transform of the memory effect functions and the hydrodynamic coefficients predicted by Havelock and Kim show satisfactory agreement. The method presented herein can be extended to solve the problem for an arbitrary body.
View full abstract
-
Toshio FUJIMOTO, Tadashi SOH
Article type: Article
Pages
95-103
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
Blades stress conditions of Highly Skewed Propellers (HSP) become severe with the increase of skew, so in designing HSP it is necessary to estimate the blade stress exactly. The authors carried out the finite element analyses of HSP blades using three-dimensional elements, and l)confirmed that numerical results agreed well with experimental ones by strain gauges, and that finite element method was very valuable, and 2)developed SPROSAS (Screw Propeller Blade Stress Analysis System) for the purpose of efficient analysis of HSP blade, and 3)confirmed through calculations of blade series with different skews that maximum stresses and deformations of the blades increased remarkably with the increase of skew.
View full abstract
-
Hiroshi KAWABE, Masatoshi BESSHO
Article type: Article
Pages
105-111
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
The singularity method or so-called boundary element method is treated the axisymmetric elasticity problem. Various representations of the displacement field to facilitate computations are proposed. Morover, integrating kernel functions analytically in earch boundary element, the accuracy of computations are sufficiently well preserved.
View full abstract
-
Toshimasa KAWANISHI, Masamitsu MATSUSHIRO, Wataru KATOH
Article type: Article
Pages
113-117
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
As the ocean development has progressed, the studies for ocean structures have increased. With the process of those studies, it is necessary to develop the various testing machines for ocean structures. Especially, in the areas where the earthquake often occurs like Japan and West Coast region of the United States of America, we must naturally design a ocean structure considering the earthquakes. Therefore experiments with shaking a underwater model has become important. We have studies to make a new underwater biaxial shaking machine for ocean structures. It is used for measurement of added mass, resonance characteristics and dynamic pressure acting on a structure. This article tells about the designs of new type biaxial shaker.
View full abstract
-
[in Japanese]
Article type: Article
Pages
119-128
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
[in Japanese]
Article type: Article
Pages
129-132
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
133-134
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
135-139
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Appendix
Pages
App7-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Cover
Pages
Cover3-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
-
Article type: Cover
Pages
Cover4-
Published: March 30, 1982
Released on J-STAGE: March 30, 2018
CONFERENCE PROCEEDINGS
FREE ACCESS
