造船協會論文集
Online ISSN : 1884-2062
ISSN-L : 0514-8499
1955 巻, 97 号
選択された号の論文の19件中1~19を表示しています
  • Tetsuo Nishiyama
    1955 年 1955 巻 97 号 p. 1-8
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    The problem considered is the forces and moment upon a submerged hydrofoil which is moving at the same speed and in the same direction as an infinite train of waves.
    The expressions for the lift, wave resistance and moment are carried to the second order and numerical calculations are made. Curves are given showing the variation of the characteristics for various phase of waves and Froude number. And also the comparisions with the corresponding value in still water are made.
  • Hajime Maruo
    1955 年 1955 巻 97 号 p. 9-16
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
  • 乾 崇夫, 岩田 達三, 沈 炳
    1955 年 1955 巻 97 号 p. 17-25
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
  • Hajime Maruo, Sukesada Matsubara
    1955 年 1955 巻 97 号 p. 27-35
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
  • Yoshihiro Watanabe, Naoto Yamagami, Shosuke Inoue, Daikaku Manabe
    1955 年 1955 巻 97 号 p. 37-42
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
  • 廣渡 智雪
    1955 年 1955 巻 97 号 p. 43-56
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    In order to measure the forced vibration of a ship excited by an oscillation exciter simultaneously at many measuring points, the author has completed a set of (ten in number) electrical vibrographs applying the variable inductance type of gauges. Making use of these vibrographs, the author has carried out a series of ship vibration experiments on four newly built ships. In this paper the author represents the principle, the construction, and the results of calibration of the vibrograph, and the results obtained on ship vibration experiments.
    The results obtained on vibration experiments are as follows,
    (1) Making use of these vibrographs, it has become possible to measure not only natural frequencies, but also instantaneous vibration profiles of a ship.
    (2) It has been made clear how natural frequencies of the vertical flexural vibration of a ship moored alongside the quay are effected by wall and depth of water.
    (3) The effect of the irregularity of angular velocity of the oscillation exciter upon the mode of vibration of a ship has been made clear.
  • 山本 善之
    1955 年 1955 巻 97 号 p. 57-68
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    In the case of plastic buckling of a structure, the critical state largely depends upon the initial deflection; this makes the load in the critical state decrease. In the present paper, as regards column and plate with initial deflections, their behavior under compressive load is theoretically investigated, by using the so-called Shanley model and the extended Shanley model for plate.
    Even if the critical stress for column or plate without any initial deflection is within the elastic range, the existence of the initial deflection makes the critical stress decrease. In the case of the plate with small initial deflection, it is confirmed that“the greatest lower bound of the Kármán state” proposed by the present author in his previous paper [5] is regarded as the critical state for practical purpose ; when it is compressed one-directionally, the stress in this state is almost equal to the so-called reduced modulus stress in classical sense. Whatever the initial deflection may be, the critical stress of compressed column or plate compressed one-directionally is not less than the stress, peEt∞E, where pe is the elastic critical stress, Et∞ is the tangent modulus corresponding to large tensile strain and E is Young's modulus.
  • 安藤 文隆
    1955 年 1955 巻 97 号 p. 69-78
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    Many experiences about“corrugation of bottom shell plating”were reported recently. This is the phenomenon to be seen when the stress on the surface of plate after buckling exceeds the yielding point, and is called the permanent buckling.
    In this paper, the author dealt with the plate problem after buckling of bottom shell plating according to the large deflection theory, and estimated the limiting stress of this failure in such cases of flat mild steel plate, high tensile steel plate, suffering water pressure, and having the initial deflection.
    After several considerations, the author concluded, as the effectiveness of panel breaker and the influence of the initial deflection, essential difference existed between large and small ships.
  • (第三報) 吃水及びトリムの影響について
    秋田 好雄, 越智 和夫
    1955 年 1955 巻 97 号 p. 79-86
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    On the problems of the dynamical strength of sh ips going in waves, especially on the problems of the slamming of ships, we have tried the experiments in the experimental tank by towing the six metre model ship, made of brass, and the influences of the wave lengths and heights were investigated in the former reports.
    In the present paper, the experiments on various ship draughts and trims when wave length and height are constant are investigated. From the experiments, the following principal conclusions may be drawn,
    (1) Slamming occurs as the encounter period of ship and wave Te closes to the period of pitching and heaving coupled motion of ship Tph, and abates as it recedes.
    (2) The cause of slamming is due to the coupled motion of pitching and heaving, but pitching is preeminent.
    (3) The pitching angle, the maximum rise of bow, the phase lag between pitching and heaving, the phase lag between wave and pitching, all these factors have the important influences on the cause of ship slamming.
    (4) The statical pressure difference of the maximum and minimum bottom pressure at ship bow increases in the slamming zone.
    (5) The impact bottom pressure indicates the maximum value when d/L=0.0325, and the impact pressure ratio at ship bow amounts to 11.6.
    (6) The maximum impact bottom pressure changes linearly with the change of ship trim. It is given approximately as the following formula
    Max.ζ0=11.0+176(Trim/L)
    (7) The mean hogging stress at deck, having no consideration for the impact stress due to slamming, shows a tendency to increase remarkably with the occurrence of slamming ; while the mean sagging stress scarcely increases. This property is the same in any ship draughts and trims.
    (8) In slamming zone, the impact compressive stress is recognized on ship deck, and indicates the maximum value when d/L=0.0325. This impact stress also changes linearly with the change of ship trim.
    (9) The maximum ship draught which causes the slamming throughout all ship speeds is ds/L=0.062.
    (10) The minimum ship speed which causes the slamming throughout all ship draughts is Vms=0.54M/sec (F=0.42). This value perfectly coincides with the value which were obtained in the wave length experiments.
    (11) By comparing the measured stresses with calculated ones, the effective wave height ratios η are obtained.
    (i) Hogging ηH indicates the maximum value when d/L=0.0325.
    (ii) Hogging ηH indicates the maximum value when even keel.
    (iii) Sagging ηS has a tendency to increase with increase in ship draught.
    (iv) Sagging ηS indicates the minimum value when even keel.
    (v) η in high speeds become fairly large compared with η in low speeds, while the increasing percentage of η owing to the Smith's correction are nearly the same, irrespective of ship speeds in any ship draughts and trims.
  • 石山 一郎
    1955 年 1955 巻 97 号 p. 87-93
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    The magnetic oscillographs have hitherto been used generally as the multichannel recorder when the dynamical strains are measured, but they are inconvenient to observe and compare the phenomena directly. In case of the Brown tube, it is difficult to picture many electron guns in one tube, therefore the instruments which have more than two electron guns have not been of practical use.
    By using the high speed scanner method, the author succeeded to measure the phases, wave forms and amplitudes of five phenomena of ship strain and vibration in direct vision at the same time.
    This apparatus has been used not only for measuring the strains and vibration of the tests in the experimental room, but also for measuring the strains on the actual ship“Hokuto-maru”in the sea going test for a long time.
    In this report, the author describes on te outline of the measuring apparatus and the results of its application.
  • 第3報 撓み変形及び残留応力
    木原 博, 増淵 興一
    1955 年 1955 巻 97 号 p. 95-104
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    This report is the third part of serial experiments which are being made to survey the effect of welding procedures on the shrinkage, distortion and residual stresses of welded joint.
    Angular change of welded part, the deflection of specimen due to angular change and residual stresses are studied in this thesis.
    The constrained ring form specimens were used. The size of specimen and welding conditions were mentioned in Part I and II.
    The measurement of angular change was performed by comparater and dial gauge. The deflection of specimen was measured by dial gauge.
    The change of reaction stress during multilayer welding, residual stress and the stress released by slitting along the weld line and by cutting out the weld metal were also measured by electric wire strain gauges.
    The main results obtained are summerized as follows:
    1) Relation Between Augular Change and Deflection of Specimen
    The deflection due to welding is found to be calcurated from the angular change as a problem of elastic dislocation. The relation between angular change φ1 and deflection δ of ring form joint is shown in equation (2). An example of the value of H(ρ, θ) in equation (2) is shown in Fig. 3-4.
    2) Relation Between Angular Change and Weight of Deposited Metal
    The relations between angular change and weight of rod consumption per unit weld length for various types of bevel are shown in Fig. 3-5. The angular change mainly increases at the welding of 2nd or 3rd layer. Chipping has little effect on the angular change.
    3) Change of Reaction Stress During Multilayer Welding
    An example of the change of reaction stress during multilayer welding is shown in Fig. 3-8. The reaction stress can be calcurated from the transverse shrinkage as a problem of Volterra type dislocation.
    4) Relation Between Residual Stress and Dislocation
    The stress (circumferential strain εθ) released by slitting along the weld line is shown in Fig.3-9. The dislocation due to slitting is shown in Fig. 3-10. The stress distribution calcurated from this dislocation (curve 1'-5') fairly coincides with that of actually measured (curve 1-5). The equations of this calcuration are shown in equation (3) and (4).
    The changes of stresses due to slitting, cutting out the weld metal and fine cutting are shown in Fig. 3-11 (a), (b), (c). The curve 3 of Fig. 3-11 shows the residual stress due to welding.
    From these experiments it is shown that the residual stress transverse to the weld line seems to be calcurated from the dislocation due to cutting along the weld line as a problem of elastic dislocation of higher order.
  • 木原 博, 楠田 忠雄, 飯田 國廣, 笹山 徳太郎, 竹内 功
    1955 年 1955 巻 97 号 p. 105-113
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    The object of this paper was to provide a basis for substantiating current specifications governing the use of intermittent fillet welds to connect the component parts of structural members. For instance, the bending rigidity is varied from a laminated girder to a solid one according to the type and size of fillet welds. So we studied in this paper the effects of leg length, pitch and flange thickness on the bending rigidity of a composed I-beam with various type and size of continuous or intermittent fillet welds. The concentrated lateral load was applied to a welded I-beam with both ends supported, and the deflections measured at nine points by dial gauges were compared with that of a solid one with the same cross section. The bending rigidity coefficient η of a welded girder can be estimated by equivalent leg length from this experimental results as follows.
    η=1/(K1-K2/1)+K2tanhφl/2/φl+K32l2(1-2tanhφl/2/φl)
    and φl=α(2Le/t1)β{γ+δ(2h1/t2)}
    where
    K1={1+6h22EI0/l2(2I1+I2)G}/1+12kEI0/l2A0G
    K2=24EA1(h1+h2)/l2G{h22(h1+h2)/2I1+I2-1/t2}/1+12kEI0/l2A0G
    K3=24A1(h1+h2)2/2I1+I2/1+12kEI0/l2A0G
    In respect of ultimate load, as it was varied from the various conditions such as leg length, pitch, joint types and dimensions of specimens, the ultimate load of the staggard was higher than the chain if the leg length was same. Types of fracture, classified in three types namely shear fracture of fillets, lateral buckling and local buckling, should be considered in case of the estimation of ultimate load of specimen.
  • 内田 勇
    1955 年 1955 巻 97 号 p. 115-126
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    In the first report, observation was made on the two dimensional flow, where it was proved that stream lines and stream velocities are identical with the result of hydrodynamical calculation. In this 2nd report, the author intends to proceed into three dimensional flow. This time, however, experimental method was mainly substituted for hydrodynamical calculation, since the calculation is hardly possible in the field of three dimensional flow. To begin with, some fundamental experiments were made to clarify the scale effect among model experiments in water current, that in air current and the facts in actual ships. The result finally reached is that efficiency of ventilation in actual ship can be measured by performing model experiments in water current.
  • 志波 久光
    1955 年 1955 巻 97 号 p. 127-134
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    The author lighted upon the fact that the phenomenon of Kármán vortex was applicable to the speed meter by theoretical study and various experiments, the details of which were already described in the Report of Ship Experiment Tank in Tokyo, No. 6.
    Then the author tried to realize the above principle actually upon the ship speed meter, the details of the mechanisms of which, and also its test results with an actual ship, are described here in this paper.
  • ねぢり疲労について
    原 三郎
    1955 年 1955 巻 97 号 p. 135-148
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    More than 6.5% of the propeller shafts of Japanese ships classed to the Nippon Kaiji Kyokai (The Japanese Marine Corporation) have fractured, cracked, or badly corroded for these six years.
    It is considered that most of the above damages have been resulted from the corrosion fatigue caused by sea water corrosion combined with repeated stress.
    In torsional corrosion fatigue, to which this paper will be limited to refer, it is peculiar that number of small cracks, so-called“cross marks”or“star marks”which unexceptionally generate at 45 degree to the axis of shaft, appear at first on the surface of the shafts even under small stress, and rapidly develop into the fracture.
    In order to explain the behavior of fracture and also to determine the allowable torsipnal stress, the author has tested small finished steel specimens subjected to repeated torsional stress and the corrosion by drops of sea water and found that the fatigue limit does not almost exist for 108 reversals and that such small cracks as“cross marks”found on the actual shafts also generate on the surface of the specimens.
    From the results of the above tests as well as the statistical analysis of the service data on the shafts, the author concludes the condition of the damage of the propeller shaft under sea water corrosion as follows :-
    (1) The fracture will occur in early stage of use, when torsional vibrating stress exceeds ±350kg/cm2
    (2) Cracks so-called“cross marks”may be found after considerable period of use at such locations of the shaft that concentration of stress exists when the stress is between ±350kg/cm2 and ±100kg/cm2.
    (3) Cracks will not occur, when the stress does not exceed ±100kg/cm2.
    As it is difficult to limit the torsional vibrating stress of the shaft within ±100kg/cm2 in all working range of revolutions, especially for medium and small internal combustion installation, the only recommendation to clear the damage of the propeller shaft is to protect it from sea water corrosion by good continuous brass sleeve liner.
  • 瀬尾 正雄
    1955 年 1955 巻 97 号 p. 149-155
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    After we have investigated some experiments of several oil pressure burners in performance, made a trial manufacture of several oil return burners and compared them with Todd burner in performance.
    In consequence, the trial burners are satisfactory in performance and seem to be useful to the practice. In addition, we have studied several experiments about rotary oil burners.
  • 八島 信雄
    1955 年 1955 巻 97 号 p. 157-161
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    Since the first turbocharged 2-cycle Diesel engine in this country was delivered as the main motor of m. s. “ARIMASAN MARU”, 7 vessels are now in service, Propelled by the same type of engine which were built by Mitsui Shipbuilding and Engineering Co.
    In this report are given some of service results obtained from the above vessels which are connected with features of turbocharged type.
    The efficiency drop of the turbocharger due to fouling of turbine as well as compressor blades and guide vanes has proved of little importance during a world-round trip without overhauling or cleaning, while the effect of different sea water as well as ambient temperature on engine performances seems the same as with the case of non-turbocharged engine. No difference has been observed either on the cylinder liner wear between turbocharged and non-turbocharged engine, both of which are running on low grade fuel.
  • 出雲 路敬博
    1955 年 1955 巻 97 号 p. 163-169
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
    The new type of large two stroke marine Diesel engine, RSD 76 type, was manufactured by Kobe Shipyard & Engine Works, Mitsubishi Heavy Ind., Reorganized.
    The paper presents the features in construction and performance of this type of engine, and satisfactory service results of ship.
  • Yoshihiro Watanabe, Naoto Yamagami, Shosuke Inone, Daikaku Manabe
    1955 年 1955 巻 97 号 p. 171-181
    発行日: 1955年
    公開日: 2007/05/28
    ジャーナル フリー
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