Bulletin of JSME
Online ISSN : 1881-1426
Print ISSN : 0021-3764
15 巻, 85 号
選択された号の論文の12件中1~12を表示しています
  • Hisashi OHUCHIDA, Akio NlSHIOKA, Ichiro KITAMURA, Etsuya KUBOKI
    1972 年 15 巻 85 号 p. 777-786
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    This paper presents the fatigue test results of steel shafts built-up by welding of 20 and 60 mm in diameter under rotating bending. Using carbon steels for base metal and austenitic stainless steel electrode for build-up welded metal, the influences of build-up welding on the fatigue strength of notched specimens and of build-up welding and shot-peening on the fatigue strength of shrink-fitted shafts were investigated. The following conclusions were drawn. (1) By the build-up welding using an austenitic stainless steel electrode, the fatigue strength of notched specimens increased. (2) In the shrink-fitted specimens built-up by welding, the fatigue strength was slightly lower than that of base metal. However, the fatigue strength was remarkably improved by shot-peening. (3) The fatigue strength of notched specimens built-up by welding can be estimated by calculation.
  • Hiroshi HANZAWA, Michiya KISHIDA, Masamitsu MURAI, Kenzo TAKASHINA
    1972 年 15 巻 85 号 p. 787-795
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    Stress analysis for a circular cylindrical shell having two circular cutouts of equal size is worked out. The following four cases are treated. A circular cylindrical shell having two circular cutouts of equal size (a) in a longitudinal direction under uniform tension, (b) in a circumferential direction under uniform tension, (c) in a longitudinal direction under internal pressure and (d) in a circumferential direction under internal pressure. The method of Green's general biharmonic analysis is extended to this problem and the boundary conditions along the edge of cutouts are satisfied by the point-matching method. Numerical solutions are obtained for three kinds of diameter of circular cutout and four kinds of center-distance of the cutouts. Especially, in the cases of (a) and (b), the results are compared with those of the flat plate.
  • Yoshio ANDO, Kunihiro IIDA, Tadahiko KAWAI, Genki YAGAWA, Fumio KIKUCH ...
    1972 年 15 巻 85 号 p. 796-804
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    This paper presents a finite element method for large deflection elastic-plastic analysis of shells of revolution. The piecewise linear procedure is employed and nonlinearity can be dealt with as the accumulation of linear analyses of numerous loading steps. As for the incremental stress-strain relation in the plastic range, Reuss' equation is used. Especially, a trial of method of treating snap-through buckling is proposed. Some numerical examples are given in order to demonstrate the validity of the present method, and the results are generally satisfactory.
  • Hiroshi ARAI, Susumu SATO
    1972 年 15 巻 85 号 p. 805-815
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    The box type structure of a container or freight car body set on four supporting points is subjected to simultaneous torsion and bending at middle planes when changed into the state of being supported at three points. In the case of f freight car, excessive torsional rigidity of the body is said to be one of the causes of derailment and in the case of a container, insufficient torsional rigidity may cause an accident of the door failing to open. We tried theoretical and experimental analysis on the shell of variable rectangular profile to study a general concept on stress distribution, deformation and the influence of end plates and bulkhead. As the result, it has been made clear that so far as this model is concerned, pure torsion accounts for 70% of the apparent torsional angle measured in the test with real structure, when both end plates are present, but when there is only one end plate, pure torsion accounts for 5% of that angle, the rest being due to profile variation.
  • Kichinosuke TANAKA, Tomoaki KUROKAWA
    1972 年 15 巻 85 号 p. 816-821
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    According to the one-dimensional elastic theory, it is well known that step waves of stress and strain propagate when two semi-infinite bars collide with each other. However, to describe precisely, the adiabatic deformation causes a thermal deviation along the bars. Consequently, the heat flow thus produced has an effect on the stress and strain waves. In this paper, the problem is formulated as a coupled transient phenomenon using the one-dimensional equation of motion, the thermal stress-strain relations and the equation of heat flow. The strain and temperature distributions are obtained. It is found that the wave front propagates with velocity c0=√(E<SUB)T/ρ> (ET: isothermal Young's modulus). the strain is observed even in the region ahead of the wave front, and the magnitude of the strain behind the wave front is nearly constant but a little smaller compared with that of the ordinary elastic theory.
  • Ryoji KOBAYASHI
    1972 年 15 巻 85 号 p. 822-829
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    This paper is concerned with the stability of the laminar boundary layer in an incompressible, electrically conducting fluid along a concave wall in the presence of a uniform external magnetic field perpendicular to the free-stream direction and parallel to the wall. The solid wall is assumed to be an electrical insulator or perfect conductor. The neutral stability curves in the relations of Gortler parameter Gθ to the nondimensional wave number σθ are presented for several values of the Hartmann number Ha. Attention is paid to the effect of variation of the streamline curvature over the concave wall in a direction normal to the wall on the condition of the neutral stability. Further consideration indicates that a change of the basic velocity profile in the boundary layer affects the stability curve in the same order of magnitude as the one in the case where no magnetic field is present.
  • Tomitaro TOYOKURA, Shiro AKAIKE, Hisao HOSAKA
    1972 年 15 巻 85 号 p. 830-839
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    In this paper, flows in axisymmetric channels between a curved casing and a boss without blades, where the impeller inlet of the mixed-flow and radial-flow turbomachines existed usually, were studied experimentally and theoretically. Measured velocity and pressure distributions were compared with those calculated by the relaxation method of Laplace's equation and some approximate methods. Furthermore, boundary layers on the casing and boss walls were discussed in detail. Velocity distributions of a ;main flow in the channel were very different from uniform ones. As the local pressure drop on the curved casing wall was observed, its effect on the cavitation performance was pointed out. The main flow in the curved channel was not affected by the boundary layers on the casting and boss walls near the entrance.
  • Hideo OHASHI, Norikatsu ISHIKAWA
    1972 年 15 巻 85 号 p. 840-847
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    For the calculation of unsteady flow around an airfoil, the following assumptions are usually made: 1) Wake is straight, 2) Shed vorticities move downstream with uniform velocity, 3) Kutta-Joukowski's condition holds at the trailing edge. To estimate the validity of these assumptions, wake pattern of a translatorily oscillating airfoil in a uniform flow was visualized by Schlieren method. Instantaneous wake patterns were photographed at reduced frequency between 1 and 19. Observed wake patterns were classified into three types. The range of reduced frequency and oscillation amplitude for each type was given. Kutta-Joukowski's condition was found to be valid at any test condition in the sense that a dividing stream line detached the airfoil at the trailing edge.
  • Teruo SAKURAI
    1972 年 15 巻 85 号 p. 848-857
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    Experiments were carried out to study diffuser performance in off-design conditions of turbomachines. Test apparatus consists of the diffuser and a set of approaching channels, which give various circumferential velocity distributions at the inlet. (1) A calculation method for boundary layer growth and diffuser performance was obtained as an extension of the calculation for logarithmic spiral diffusers. Here the main flow velocity is treated as a sum of a fundamental (log. spiral) part and an additive part. (2) In regions which are free from the direct influence of the inlet flow, forms of the secondary flow and pressure distribution are invariable regardless of variations of the inlet flow. (3) In the range of low flow-rates, the effective inlet radius becomes large and it decreases the pressure-rise. (4) It was also made clear that cases with leading edges could be treated as applications of the logarithmic spiral diffusers.
  • Nobuyuki AKIYAMA, Yoshiro ANNO
    1972 年 15 巻 85 号 p. 858-865
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    In this report, the discharge property of a taper land spool valve is analyzed theoretically on the assumption of laminar flow and verified experimentally. Theoretically, we assume a taper land channel as a two-dimensional divergent or convergent channel, and obtain a pressure loss with approximate velocity profile. In the inlet part, we apply the similarity of velocity profile to a boundary layer equation and obtain a pressure loss in the inlet length. Experimentally, we make a model of two-ports valve and obtain precise data. Taper angle is set to be 1.5°∼6°, spool displacement 0.5∼4 mm, Reynolds number 10∼1, 200. In this range we experiment, and compute the discharge property in the same range. In the result, experiment data show good coincidence with computation result. Further, the influences of back pressure of the valve are also discussed.
  • Norimune SODA, Yoshitsugu KIMURA, Masami SEKIZAWA
    1972 年 15 巻 85 号 p. 866-876
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    Wear of steel rollers has been investigated under unlubricated rolling contact with a small amount of sliding. A four-roller machine is used for the experiment; the velocity difference between the mating rollers is kept constant, while the slip ratio and the normal load are varied. A common feature is found in the wear characteristics when either the slip ratio or the load is varied. No appreciable wear takes place up to a certain critical value of each of the above parameters, and once this value is exceeded, wear begins to increase with the increase of the parameter. These wear characteristics are analyzed based on a microslip model, which was introduced for the interpretation of the frictional characteristics under such a rolling-sliding contact, by Soda and Watanabe. The extent of microslip region is determined and the macroscopic sliding wear law is applied there. The experimental and analytical results show a satisfactory agreement. It is concluded that the mechanism of the wear under rolling-sliding contact can be regarded as a usual sliding wear in the microslip region which appears in the contact area exceeding some critical running conditions.
  • Toshio AIDA, Hiroshige FUJIO, Mikio NISHIKAWA, Ryuji HIGASHI
    1972 年 15 巻 85 号 p. 877-883
    発行日: 1972年
    公開日: 2008/02/15
    ジャーナル フリー
    In this paper, the authors investigated the relationship between case-hardening condition and the bending fatigue strength of gear tooth under impact load. The results obtained from this experiment are summarised as follows: (1) There exists an optimal thickness of case-hardened layer for bending endurance limit of case-hardened gears, but it differs from an optimal thickness of case-hardened layer for impact bending strength. And an excessively large thickness of case-hardened layer causes an decrement of impact bending strength. (2) When impact load P is less than 0.63Pim' (Pim': impact fracture load), and impact velocity is below 5m/sec such as in this experiment, impact load has no influence on fatigue strength. (3) Few times applications of an impact load, which is nearly equal to endurance limit load, cause an increment of bending endurance limit.
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