A semi-infinite plate with a step and a crack originating from its angular corner is analyzed as a thin plate bending problem. Taking uniform bending moment as the load condition, stress distributions are investigated. Stress intensity factors which are important in linear fracture mechanics are analytically calculated for various crack lengths. The influence of the step and the angle of the corner is investigated. The relation between stress intensity factor and Poisson's ratio is also investigated. A rational mapping function which is formed as a sum of fractional expressions and the complex variable method are used for the analysis. By using this mapping function, a closed solution is obtained which is exact for the shape represented by the rational mapping function. By using a rational mapping function of a sum of fractional expressions, the stress analysis for a comparatively arbitrary shape can be carried out.

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This paper considers the response of an elastic plate to a moving load. The plate is resting on a Pasternak foundation and the load moves uniformly with a constant velocity. The deflection of the plate is expressed in the form of integration. Combinations of the velocity and the foundation parameters yield the expression in five types of integration. It is show that the critical velocity of the load becomes larger than that of the Winkler foundation due to the presence of a shear layer in the Pasternak foundation. Numerical computations are carried out for some combinations of the parameters.

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An isothermal thin water film, flowing concurrently with an air stream in a horizontal duct was investigated. This paper gives experimental results on the celerity, length and frequency of waves besides the characteristics of film thickness such as mean, maximum, minimum and height of them in two-dimensional wave and disturbance wave regions. These quantities are discussed in connection with the flow mechanism in these two regimes. As the result it is made clear that the two-dimensional wave region is divided into two regimes ; in the first regime the thickness is relatively large and surface tension is one of the main factors to control the celerity. In the other regime which is adjacent to the non wetting region, the mean film thickness is very small and the celerity is controlled mainly by the dynamic pressure of the air flow. Furthermore, the flow mechanism of base film in disturbance wave region is similar to that in pebble wave region of same water flow rate.

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The behavior of a single particle which moves in the stagnation flow of an ideal fluid is studied theoretically, assuming that the drag force is proportional to both the first and second powers of the velocity difference between a particle and a fluid. In the case that the interaction force is assumed to follow only Stokes law, an analytic solution is sought and the critical condition for collision is obtained. The drag force based on the second power of the relative velocity tends to prevent the particle collision on the wall. These characteristics are clarified through the effective collision radius, and so on.

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The influence of the buoyancy force, which acts on the particles, on a flow induced in a particle-fluid mixture by an oscillating flat plate is studied theoretically, assuming that the terminal velocity of rising or falling particles is smaller than the velocity of the oscillating plate. The migratory movement of particles due to the component of gravity force perpendicular to the plate affects the oscillatory motion of the particle-fluid mixture, while that due to its component parallel to the plate does not affect it. The influence of the buoyancy force on the flow is clarified in terms of the boundary layer thickness, the wavelength of the viscous wave, the particle velocity, the viscous stress, and so on.

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A vortex oscillator, which has a double input vortex chamber and two conduit-capacity systems, is studied theoretically and experimentally. An oscillator with a single conduit-capacity system is also examined. A mathematical model of this type of oscillator is presented and its validity is examined by experiments. The stability of the equilibrium state of the system is discussed. Higher modes of oscillation occur in the system under certain conditions when the compressibility of the working fluid is relatively large. The frequency of the higher mode coincides with the natural frequency of the same mode of the conduit-capacity system of the oscillator. Relaxation oscillations occur under certain conditions also. The experimental data were found to be in good agreement with theoretical predictions.

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A transfer matrix equation relating the pressure and volume flux in tapered fluid lines is derived under the assumption that the rate of divergence (or convergence) of the line is comparatively small. The model employed in the analysis is one of an unsteady viscous flow, that is, the frequency-dependent effect of viscosity is taken into consideration. Natural frequencies and frequency response curves of the line systems are calculated from the matrix, and dynamic characteristics of systems are discussed under various pipe-end conditions. The experimental data obtained from frequency response tests are compared with theoretical analysis, the validity of which is thus ascertained.

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This paper deals with a special method of using the hydraulic copying system called polygon turning, namely turning of a noncircular cross section. Considering the relation between copying accuracy and the dynamic characteristics of the hydraulic copying system, the following results were obtained for estimation of error and improvement of the accuracy. (1) The error resulting from a simple polygon turning can be calculated from dynamic parameters, particularly from time constant, of the hyaraulic copying system and shape of model of a cross section for the turning. (2) The dynamic performance parameters of the copying system were suitably obtained from field measurement of frequency response using a plate cam as an input signal generator. (3) A method for modification of model shape to reduce the resultant output error was developed and applied to a polygon turning and a turning of helical shaft or screws. The validity of the method was confirmed by experiments.

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Validity of the accelerated two-phase flow analysis in higher quality or higher pressure regions than in the previous paper is shown, using the wall frictional coefficient and interphase frictional coefficient determined from Ogasawara's experimental results. Convergent-divergent flow analyses are made and a general two-phase critical flow condition is examined. It is shown that |dP/dZ|→∞ should occur at the critical flow point. This is justified by way of the solution of simultaneous differential equations governed by basic law. The relations of two-phase flow variables in the critical flow are obtained. The two-phase critical flow rate is not determined simply in terms of pressure and quality at the critical flow point, but through the flow history to the critical flow occurrence. The source for the misleading relation in the past two-phase flow analysis is also indicated.

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A new parameter is proposed for prediction of the transition between flow patterns such as bubble, froth and annular flow, in both the subcooled and low quality regions of boiling flow. This parameter is derived from the theoretical calculation method of void fraction, which has been reported, on the assumption that the flow pattern transition occurs at a value of average void fraction over the cross section of the flow. A flow map is also presented which reasonably correlates the experimental results covering the following conditions ; pressure : 1∼98 ata, heat flux : 2×10⁴∼5×10⁶kcal/m²h, and mass velocity : 40∼5400kg/m²s.

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This paper reports computative and experimental investigation on the fuel supply characteristics in the transition region where the fuel supplied from main-system begins to join the fuel discharged from the idle-system in the fixed-venturi type carburetor. The investigation have revealed the effects of geometric parameters in both systems by introducing the relation between the carburetor air flow and fuel levels in a main well and an air bleed tube on the fuel supply characteristics in the transition region. The computative simulation developed in the report is available for predictings the fuel supply characteristics not only in the transition region but also the whole regions.

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Train noise is dominated by the wheel flexural vibration which is caused by interactions between wheel and rail. Since the wheel is remarkably thick, the flexural vibration can not be analyzed on the assumption that the wheel is a thin circular plate. The effects of shear deformation and rotatory inertia should be taken into consideration. The wheels which are used in Japanese rapid transit (Shinkansen) trains may be assumed to be a circular plate with stepped thickness. In this paper, the vibration is theoretically analyzed with due regared to the above facts, and the results are compared with the experimental ones. All results are in significant accordance, and some interesting characteristics are obtained.

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A method to solve exactly the flow of a fluid film of self-acting gas-lubricated journal bearings and an approximate method using transformation of variable which renders the basic equation quasi-linear are presented. The analysis is conducted for static and dynamic performance with the parameters varied. It turned out that the proposed exact and approximate methods are useful.

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The limiting loads for scoring of the crossed helical gears expressed with Hertzian pressure were compared with those of the FZG spur gear tests and of the roller tests. The limiting loads for scoring of the crossed helical gears are very low and are changed not so widely according to the kind of oil. As a result it can be seen that the crossed helical gear is under quite unfavourable condition for the formation of a lubricating oil film. In order to increase the limiting load for scoring, various kinds of surface heat treatments and material combinations were tested. The load was stepped up from the first stage to the next higher stage successively according to the load stage.

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The first report stated that the nylon gear was available for use in power transmission. But nylon gear has a problem of abrasion. In this paper, confirming this abrasion, is investigated the dependency of abrasion on load and sliding velocity of tooth in nylon gear for power transmission which meshes with steel gear. It has been confirmed that the phenomenon like a creep occurs on a tooth of power transmission nylon gear. And it has been investigated how this phenomenon influences abrasion of nylon gears.

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