The elasto-plastic bending of a clamped circular plate under a partical circular uniform load is investigated by the total strain theory and the Mises'yield condition. To solve the fundamental equations corresponding to the ranges of the elasto-plastic bending and the pure elastic bending continuously, a new paramater which indicates the appearance of the plastic region on the plate is used to rewrite the fundamental equation in the pure elastic bending range. The distribution of the bending moments and the deflection in the plate, the development of the plastic region in the meridian section, the relation between the load and the mode of development of the plastic region are discussed in regard to the ratio of radii of the loading circle and the plate.

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To solve the problem of bending action of piston rings or crane hooks, we considered an eccentric circular ring with a cut-out portion undergoing forces and bending couples at both ends. Using the theory of elasticity for plane stress and applying bipolar coordinates, we obtained correct solutions for the above problem and compared the solutions with those by the usual elementary theory. From the results of calculations, we reach the conclusion that the solution by the usual elementary theory is reliable, only when the eccentricity between the centers and the difference between the radii of two circles of the boundaries are small.

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This paper deals with the thermal stress analysis of an infinite circular elastic cylinder heated on the surface axisymmetrically by heat sources, which move at a constant velocity in the axial direction. The underlying heat conduction problem, as well as the associated thermoelastic problem, is attacked with the aid of the exponential Fourier transform on the assumption that the cylinder is homogeneous and isotropic with respect to both its thermal and elastic response and that the temperature distribution of the surface is prescribed. The solutions for the temperature and stress distributions are obtained in the form of infinite integrals. Numerical examples, which are carried out for two specific distributions of the surface temperature, show a marked influence of the velocity of the heat sources on the distribution of the thermal stresses.

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The nature of the fatigue damage of 7-3 brass specimens is quite the same as what occurs in 6-4 brass or in low carbon steel specimens. The damage is confined within a thin surface layer of the specimen and cannot be removed by stress relief annealing. The thickness of the damaged layer becomes greater when the applied stress is high and the number of the stress repetitions is large. The fatigue stressing hardens the material but the hardening can be removed by stress relief annealing. By taking X-ray diffraction patterns of the surface as well as of the portions beneath the surface of the specimens, it was revealed that the distortion and fragmentation of the grain in fatigued specimens decrease as the distance of the irradiated grain from the surface increases and it was concluded that, as the thickness of the severely damage layer reaches some threshold value of one or two grains thickness, fatigue cracks develop there which, in most cases, eventually cause the plain specimens to break down.

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Theoretical solutions are here presented which may be available to the understanding of dynamics in the forced-flow evaporator system. Some basic forms of various transient response curves are illustrated by using these solutions. As a main result, it was made clear that the dynamic behavior of system pressure is composed by two factors. The first factor shows the effect as lumped-parameter, and the second as distributed-parameter. It was found, moreover, that the transient response of pressure is almost determined by the lumped-parameter effect.

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The vibration of a U-bar which occurs perpendicularly to its plane is studied. The U-bar consists of one circular arc bar and two straight bars or of three straight bars. The ends of the U-bar are clamped and two legs of it are of the same dimensions and material. The frequency equations and the boundary values are obtained by minimizing the Lagrangian. The frequencies of U-bar in the symmetric vibration are calculated and shown in graphs. The experiments are carried out and their results are compared with the theoretical results.

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The cavitation aspect and the water flow in the radial-flow impeller are discussed on the basis of the experiment conducted for a wide range of discharge flow-rate, suction static pressure and revolving speed with a centrifugal pump having three dimensional blades and the vortex chamber. That is, cavitation zones in the impeller are classified into five zones, the results of observation by the strobolight on the process of growth of each cavitation zone is interpreted considering the relation between the cavitation zone and the flow condition of water in the impeller. Above all, some interesting phenomena caused by cavitation such as the discontinuous change of direction of the pump characteristic curve and the discontinuous drop of the pump head are found and the causes of their occurrence are discussed.

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The authors tried to develop upon the hydraulic conveyor an analytical method for the pressure drop in the pneumatic conveyor by T. Uematsu and T. Kano, and obtained a formula for the pressure drop in the "hold up flow" through a horizontal pipe. The experimental constant in the formula was determined on the results of experiments in flyash and sand slurries. The resulting formulas are in good agreement with the authors' result and other investigator's also within the error of measurement.

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Clear knowledge on the thrust of valves is necessary to discuss the stability of valves which plays an important role concerning the stability of a pipe line. In order to have a general idea of relations between the thrust and the lift, and between the discharge coefficient and the lift of common valves, we studied the characteristics of the most simplified valve, that is, a circular disc valve. The flow between the valve and the valve seat is very complex. The pressure distribution over the valve surface and the lifting-force were calculated analytically for various types of the flow, and examined experimentally for three kinds of disc valve. Experimental results show the correlation between the lifting-force and the discharge coefficient.

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Oil hydraulic control valves are used in an oil hydraulic system with an oil hydraulic pump or an oil hydraulic motor, etc. From the view-point of their functions they are roughly classified into three types, that is, pressure, flow and directional control. The author made experiments on some typical hydraulic control valves, and compared the results with those of analyzing all performances of the valve to make their performances clear ; they are the performances of the direct and pilot valve type relief valve, the reducing valve, the second pressure of which is constant, the flow control valve with pressure compensator and the spool valve.

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When solid particles flow through the impeller of a volute pump with water, the behavior of particles is not always clear. The writers recorded photographically the trajectories of solid particles in the impeller using a high speed camera. In this paper the experimental results are cited, especially those on the relative velocity and its direction at the impeller exit. Moreover the numerical method of calculating the trajectories is demonstrated.

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In this report, the author has treated the axisymmetric flow at design point in multistage turbo-machines of various vortex types, such as the constant reaction type and the exponential type, using a similar method to that described in 1st Report. Regarding the axisymmetric flow through an axial-flow turbo-machine, the radial equilibrium theory and the actuator disc theory have been expounded, but the effects of impeller breadth and blade shape have not been considered in these theories. The method described in the present paper takes these effects into account. Numerical examples are shown comparing the results calculated on the basis of the above mentioned theories.

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This paper deals with experimental studies of plasma jet. In the first part of this paper, two spectroscopic methods were employed to measure the temperature of plasma jet and the two results coincided fairly well for the range of our observation. In the second part, a thermo-fluid dynamical method was used to measure the jet temperature, several fluid dynamical properties and the heat transmitted from plasma jet to solid wall.

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A burner with a mixing-roll at an end of partition wall between fuel gas and air supplying nozzle was used. The fuel gas was flowing along the side wall of the burner, and air was supplied together with the fuel gas. The fuel gas was diffused in the air quickly by the existence of the mixing-roll. A diffusion flame in this burner was stabilized on a wake of the roll. The burning mechanism in this burner was clarified. The flame had different shapes which were stabilized under each fixed flow situation. The fuel gases were sucked into the air flow as soon as they flowed out of the fuel nozzle, and reacted soon, in the case of a turbulent flame. A turbulence intensity of the flow was increased by the existence of flame, so that eddy diffusions acted much more rapidly than in the flow that is under the same conditions but without a flame. The diffusion velocity could be made so high by the mixing-roll that the burning rate of this burner was determined by the burning velocity of fuel-air mixture only under certain conditions.

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This paper is a sequel to the investigation on effects of the connecting passage area of a divided chamber type Diesel engine on the knock intensity : The maximum rates of pressure rise in the auxiliary-and the main chambers of a swirl chamber type engine were measured from indicator cards under a light load. The test results are summarized as follows : Above 1000 rpm of the engine speed, the rate of pressure rise in the swirl chamber and the amplitude of detonation-like pressure oscillation rapidly augment as the area ratio is reduced. The relationship between rates of pressure rise in the main chamber and in the swirl chamber can be classified into three stages according to the area ratio. In the smallest ratio range the gas flowing out from the swirl chamber is delayed by the connecting passage, thus resulting in a relatively low rate of pressure rise in the main chamber compared with that in the swirl chamber. In the intermediate area range the rate of pressure rise in the main chamber is nearly equal to that in the swirl chamber. The larger area ratio gives the higher rate of pressure rise in the main chamber than that in the swirl chamber because of the burning of fuel escaping in the main chamber.

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Abnormal wear of piston rings occurs sometimes with recent marine diesel engines because of severer lubrication condition. The authors studied the mechanism of abnormal wear through analyses of the running-in process of the ring under the lubrication condition at high temperature and low speed, and the preventive measures. It was made clear that (1) the occurrence of abnormal wear was expedited by abrasion with hard abrasive generated by scuffing caused by edge loading of rings at the dead centers of stroke, (2) high alkaline cylinder oil lacked in thermal stability and deposited soft abrasive at above 180°C, causing scuffing, (3) the character of the compound of metal arising from added elements was dominant as the influence of the cylinder liner material, and total carbon and silicon contents had little effect, (4) chamfered piston rings and finishing of the liner surface by tool cutting were effective in preventing abnormal wear, etc.

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