Bulletin of JSME
Online ISSN : 1881-1426
Print ISSN : 0021-3764
19 巻, 138 号
選択された号の論文の22件中1~22を表示しています
  • Tsuneshichi TANAKA, Hideaki NAKAYAMA
    1976 年 19 巻 138 号 p. 1391-1400
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    In the previous report, the authors had reported on the impact fatigue characteristic composed of twoaspects, i.e., strength aspect and inelastic strain behavior aspect, through a series of fatigue tests conducted with several sorts of metallic materials. In the study reported here, the investigations under low temperature atmosphere of -50°C were made using 0.22%C carbon steel, and as the result, the impact fatigue characteristic observed under the room temperature atmosphere were revealed.
  • Tsuneshichi TANAKA, Hideaki NAKAYAMA
    1976 年 19 巻 138 号 p. 1401-1408
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    As a sequel of the impact fatigue investigation in 150 C low temperature atmosphere, a series of the fatigue tests in -100 C low temperature atmosphere were conducted. It was revealed that the impact fatigue strength became higher than the ordinary fatigue strength in the whole range of the stress cycles experimented, and this strength behavior can be interpreted such that the strain aging is hard to occur under both load conditions in such a low temperature atmosphere of -100 C, so that the fatigue strength is determined by the accumulation of the hysteresis energy only.
  • Masateru OHNAMI, Hiroshi NAKAMURA
    1976 年 19 巻 138 号 p. 1409-1419
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    The analytical and experimental results of thermal fatigue of a circular disk of structural carbon steel are presented. The periphery of the disk is cycled between two programmed temperature levels, while a water cooled sink at the inner radius is kept at lower temperature level. (1) Unsteady elasto-plastic thermal stress and the strain in the disk specimen calculated from the measurement of radial temperature distribution on the disk are in good agreement with the experimental results, in both the measurement of the diametral displacement and the X-ray residual stress measurement. (2) Number of cycles to initiation of thermal crack in the disk is predicted from the uniaxial thermal fatigue test data on the common basis of the equivalent total strain range of Mises' criterion. The propagation rate of thermal crack is also predicted on the basis of product of the rate (dl/dN) with the number of cycles N at a prescribed crack length l.
  • Takeji ABE
    1976 年 19 巻 138 号 p. 1420-1429
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    Elastic deformation of polycrystalline metals under uniaxial loading is investigated by analyzing a model of polycrystals by finite element method. Influence of free surface on deformation behavior of grains and three-dimensional restriction of grains are mainly studied. It was found that the effect of free surface on distribution of stresses, strains or constraint ratios in the stress direction in surface grains is small and confined to a very thin layer near the surface. The stress normal to surface is nearly equal to zero in the surface grain, while the strain or constraint ratio normal to surface changes. There is little effect of free surface on the distribution of stresses, strains and constraint ratios in the inner grains adjacent to the surface grains. Group of grains placed near the surface of polycrystals is found to rotate during deformation. The distribution of constraint ratios in the stress direction in the surface grains is approximately represented with cosine curve as well as that in the interior grain. It is suggested, however, that the mean constraint ratio in the surface grain is about 75-89 % of that in the interior grain, because grains are cut by surface randomly and hence the depth of the surface grains is random. It is also suggested that three-dimensional restriction is nearly double the two-dimensional one.
  • Kosuke NAGAYA, Yoshitaro HIRANO
    1976 年 19 巻 138 号 p. 1430-1434
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    This paper discusses a problem of a diffraction of plane transient waves in an infinite elastic medium with two infinitely long parallel cylindrical cavities to an impact load. In the analysis, it is assumed that an axially symmetric impact load acts at the interface of one of the cavities which is small enough compared with the others. Expressions of stresses around the large cavity are obtained by the Fourier transform method for an exponentially decaying impact load. Variations of a tangential stress around the cavity with time are shown in a numerical example.
  • Toshihide HIRATA, Masaaki WATANABE, Matsuo MIYAGAWA
    1976 年 19 巻 138 号 p. 1435-1441
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    This paper deals with the measurement and the analysis of the critical load at the elastic inatability of circular plates, whose boundary is supported by equidistantly located and concentrated loads with numbers 2m (m:integer), each of which acts laterally in the opposite direction alternately. In the case of m-2, deflection of the plate becomes anticlastic, and instability from anticlastic to synclastic occurs with an increasing deflection of the plater. Similarly, in the case of m=3, the instability takes place but the synclastic deformation does not. The critical load decreases with an increase of (diameter/thickness) ratio of the plates. Introducing a non-dimensional couple, the critical value is proved to be a fixed value regardless of the ratio. The experimental results are in good agreement with the analysis.
  • Toshio YAMAMOTO, Kimihiko YASUDA, Imao NAGASAKA
    1976 年 19 巻 138 号 p. 1442-1447
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    For demonstrating the occurrence of ultra-subharmonic oscillations, a theoretical analysis is carried out for a vibratory system with nonlinear spring characteristics of a fourth order polynomial of the displacement. The analysis shows that the ultra-subharmonic oscillations of the order 2/3 and 3/2 are easily induced, that the fourth order term is essential for the occurrence of the oscillation, and that the constant component of the oscillations caused by the fourth order term has a considerable effect on the response curve. By comparing with the analog-computer analysis, the theoretical analysis is shown to be valid.
  • Atsuo SUEOKA, Hiroshi SHIMIZU
    1976 年 19 巻 138 号 p. 1448-1457
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    The subharmonic oscillations of order 1/3 in a roller chain regarded as a system with multiple degrees of freedom are analysed under the boundary conditions that its one end is fixed and the other end is subject to lateral forced displacement. Such oscillations are excited by the fluctuations of tension, namely of the extension of the chain during vibration. The solutions for these subharmonic oscillations are obtained by applying the harmonic balance method. It is clear that only two kinds of these solutions can be realized with the limited regions of stability. Further, the modes of these vibrations and the fluctuation patterns of tension are determined and characters of their stable steady vibrations are discussed.
  • Hiroshi YAMAKAWA, Atsubumi OKUMURA
    1976 年 19 巻 138 号 p. 1458-1466
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    In this paper, it is intended to establish a general method or algorithm for solving optimum structural design problems, in which natural frequencies are involved in objective functions and/or in conditions of constraints. The proposed method has wide adaptability to various geometries of structures, by making use of the large matrix method or the transfer matrix method for vibration analysis, after discretizing structures by finite-element idealization. As Rosen's gradient projection method is also employed for optimization. technique, the present method can be applied to structures having a number of constraints and design variables even in the case that consdtraints and objective functions appear in nonlinear forms. Moreover, it is found that the procedure given here, for evaluating gradients of frequency-involved quantities with respect to the design variables, can be utilized in any eigenvalue problems and for other optimization techniques.
  • Kiyoshi SOGABE, Tatsuya SHIGETA, Heki SHIBATA
    1976 年 19 巻 138 号 p. 1467-1477
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    The present situation of the aseismic design of liquid storages and its points of issue are pointed out at first. The fundamental concepts of a systematization of the aseismic design of liquid storages are proposed based on these points of issue. The authors carried out a series of experiments and analyses to make clear the fundamental vibrational characteristics of liquid storages. An earthquake response observation of a cylindrical storage model of diameter 4.0 m and response analyses of sloshing of liquid in cylindrical and spherical storages are reported in this paper. The results are summed up into formula and nomogram which are convenient and available for the response calculation of sloshing of liquid in the aseismic design of liquid storages.
  • Naofumi FUJIWARA, Yoshisada MUROTSU
    1976 年 19 巻 138 号 p. 1478-1484
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    This paper is concerned with the synthesis of vibration isolators optimizing the riding comfort of vehicles under random excitations. Optimum control theory in frequency domain is applied to solve the optimizing problems. The theoretical implementation has been accomplished for single- and two-degree-of-freedom systems. As design examples, the optimum vibration isolators for the systems with white noise foundation excitations and with roadway excitations are synthesized. The optimum vibration isolators thus obtained can only be mechanized with active elements rather than conventional spring-dashpot elements. It is, however, possible to set up the configuration approximately with passive elements. It is found that the riding comfort of vehicles with the optimum vibration isolators is considerably better than that with conventional passive isolators.
  • Yoshiaki IWATA, Mitsuo NAKANO
    1976 年 19 巻 138 号 p. 1485-1489
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    In this paper, the active vibration absorber controlling the pressure of the air spring is applied to a preview control system of a vehicle suspension. The front half-part of the vehicle functions as the sensor for the vibration absorption of the rear half-part. The design criterion for the optimum preview control absorber is the minimization of the rms value of the acceleration under the specified constraints on the relative displacement. The optimum preview system is realized by the feedforward and feedback compensation systems. Chang's optimum control theory is applied to the optimization. The experimental results show good coincidence with the analyses.
  • Akira HIBI, Tsuneo ICHIKAWA
    1976 年 19 巻 138 号 p. 1490-1496
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    In this paper, a starting torque of a pressure balanced type vane motor is analysed and the calculated results are compared with experimental results. Bottom sides of vanes of the motor used in this work are always pushed radially by inlet pressure. Therefore the mechanical efficiency of the motor is less than 60% at start. Next, whole torque performances from start to maximum speed are investigated experimentally. And it becomes clear that the frictional torque of the motor increases with a decrease of rotational speed and it takes maximum value at start. The change of the frictional torque form start to maximum speed is continuous and its value at 0.01 rpm is almost equal to that at start.
  • Shigeru TSUJI, Hiroshi KATAKURA
    1976 年 19 巻 138 号 p. 1497-1503
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    In this paper we present the analytical and experimental results on the effect of air diffusion of a single spherical bubble in oil for both cases when pressure change as well as rotational fluid motion is present or absent. We measured the change in diameter in a case without pressure change and confirmed that an existing theory was useful when the dissolved air was initially undersaturated, if a suitable value of the air diffusivity affected by the rotational motion and the fluid temperature could be chosen. On the change in diameter in a case with pressure change, we confirmed analytically and experimentally that under a certain condition the bubbles grown under low pressure needed a long period of time to return to the initial diameter when the pressure was restored to the atmospheric one.
  • Yoshinori ITO, Toshiyuki SARUMARU
    1976 年 19 巻 138 号 p. 1504-1514
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    Real comprehension of specific character of hydrostatic transmission is gained only from investigation into respective performances of hydraulic instruments and power flow originated from engine and transferred to load through hydraulic drive system; this flow is to be regarded as a power train system. This paper takes up our investigation into and experiment in distinctive feature on characteristic formula of hydraulic drive system gained from approximate characteristic formula of hydraulic instruments. Investigation and experiment have been performed on the characteristic of a power train system combined with a diesel engine. This investigation and experiment revealed the following: Impedance of hydrostatic transmission larger than that of a torque convertor is rather similar to characteristic of gear transmission. This hydrostatic transmission provides a continuously variable speed ratio not available for gear transmission. The above features could bring forth a better power controllability different from other transmissions.
  • Toshikazu KADOTA, Hiroyuki HIROYASU
    1976 年 19 巻 138 号 p. 1515-1521
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    A mathematical model of a single droplet evaporating in high pressure and high temperature gaseous environments was investigated. The calculations cover the unsteady and steady state of droplet evaporation considering the effect of natural convection. The effects of non-ideal mixtures, the fuel vapor concentration at surface and the non-ideality of the enthalpy of vaporization were taken into consederation in order to describe the phenomena of a droplet evaporating at high pressure. All of these effects were found to be important. Non-linear simultaneous ordinary differential equations were calculated for an n-heptane droplet in nitrogen gas using an electronic computer by Runge-Kutta-Gill method. The results were presented as the size and the temperature history of a droplet and the life time, and showed a good agreement with the experimental results reported in the previous report.
  • Kenji FUJIKAKE
    1976 年 19 巻 138 号 p. 1522-1529
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    Fin efficiency and overall efficiency are very important factors to be considered in the design of finned heat exchangers. However, no suitable equation has been available to compute the efficiency of the fin surfaces, where heat conduction proceeds two-dimensionally through a thin strip and is influenced by heat conduction characteristics of the water tube walls. In this paper, equations for the fin efficiency and overall efficiency are presented for the following three cases. First, the approximate equation for fin efficiency, derived from numerical analysis in case of two-dimensional heat conduction through thin metal fins. Second, the equation for fin overall efficiency in consideration of heat conduction characteristics of the water tube walls, derived by analysis. Third, the equation for corrugated fin surface's overall efficiency derived from consideration of the influence of two-dimensional heat conduction through the fins and heat conduction characteristics of the water tube walls.
  • Yutaka TANAKA, Yuzuru SHIMAMOTO
    1976 年 19 巻 138 号 p. 1530-1538
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    In the flow field accompanying combustion, there exist three kinds of fluctuating modes such as pressure, entropy and vorticity types. Then, it can be regarded that the self driving sources of combustion oscillation originate from the mutual transforming rate and the mutual coupling processes among these three modes. However, if we restrict the oscillations to axial types only, the vorticity mode can be excluded. Among the former two modes, this report deals with the fluctuations which belong to the entropy mode. In the first place, experimental equations of steady heat release rate and temperature state are proposed. In the second place, expressions of non-steady state concentration, heat release rate and temperature are derived theoretically. As a separate subject, it was examined how and to what degree the decreasing process of entropy mode would be affected by frequency, heat conductivity, over-all heat transfer coefficient and flow velocity. The obtained results show that the temperature oscillations decrease slowly, which has been considered to be dissipated immediately behind the heat source.
  • Yutaka TANAKA, Yuzuru SHIMAMOTO
    1976 年 19 巻 138 号 p. 1539-1547
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    This paper deals theoretically with the converting processes of energy from heat release into pressure mode generation. The converting rate is calculated about several representative types of heat release distribution. The main obtained results are as follows: (1) When heat is given to a gaseous medium, 1/κ parts of this energy are transformed into the entropy mode energy, and the remaining (κ-1)/κ parts are transformed into the pressure mode energy. The latter's ratio increases fot the case that the gas is flowing. (2) When the axial heat release distributing form is a unit rectangle pulse type, the converting rate is large in low frequency regions and diminishes variously in higher frequency regions. On the other hand, for sinusoidal and cosinusoidal types, the converting rate curves have different patterns. The one is similar to the unit rectangle pulse type, the other takes a curve such that the rate has low value in low frequency regions and high value in middle- or high- frequency regions. (3) From the obtained results, it was inferred that the oscillations of middle- and high-frequencies in combustion instability depend upon the length of heat release region and the magnitude of heat release oscillations and upon their distributing states.
  • Yutaka TANAKA, Yuzuru SHIMAMOTO, Eiji FUJIWARA
    1976 年 19 巻 138 号 p. 1548-1555
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    This paper deals with calculating methods of dynamic responses about the pipe system in which combustion takes place. The converting equations from heat release rate into pressure wave generation that were proposed in the previous paper, and usual acoustic theories for normal temperature are used in the theoretical analyses. In order to compare the theoretical results with the experimental ones the following combustor and rotary throttle were produced. In this combustor, one dimensional combustion states can be attained. Rotating throttle supplies combustible mixture in a manner close to a sinusoidal oscillating type. Obtained results show that the amplitude in the combustion state becomes high in comparison to the one in the non-combustion state. It is recognized that the amplitude gain depends on the magnitude of heat release per unit time and that the main source of this gain is a pressure originating from the volumetric expansion by combustion. It is also studied how the length of combustion region, pipe length and volume exert effects on the dynamic responses.
  • Norihisa ARAI, Toshio AIDA
    1976 年 19 巻 138 号 p. 1556-1562
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    The main object of this paper to to examine the influences of force-fitting conditions, kinds of material, method of heat treatment, thickness of gear rim and size of tooth upon the deformation in each part of gear rim (diameter of tip cylinder, diameter of root cylinder, displacement over a given number of teeth, tooth profile, lead and normal pitch, etc.). From the experiments it is found that the larger the interference and the smaller the gear rim thickness and size of tooth, the larger becomes the deformation in each part of gear rim mentioned above, and deformation of tooth profile is hardly influenced by kinds of material of gear rim and method of heat treating.
  • Teruaki HIDAKA, Yoshio TERAUCHI, Kunio ISHIOKA
    1976 年 19 巻 138 号 p. 1563-1570
    発行日: 1976年
    公開日: 2008/02/15
    ジャーナル フリー
    In the previous paper, the load distribution of each planet of Stoekicht gear (Type 2K-H) was reported. In the present paper, the displacement of sun and ring gear from their basic positions was measured. Then, the relations among the dynamic loads of sun gear tooth, the load distribution and the displacement of sun and ring gear were studied. The results are as follows: (i) In the low speed region, the center of sun gear are shown with the geometrical locus irregularly coursed by various errors of gear equipment. However, in the high speed region this locus approaches to circle but the radius grows large with increase of speed. (ii) The displacement of ring gear mainly occurs by elastic deformation. The ring gear resonates when the mesh frequency of teeth coincides to the natural frequency. (iii) Variation of the dynamic load of gear tooth and load distribution are closely connected with the displacement of sun and ring gear.
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