The virtual work principles for two elastoimpact bodies are required to formulate the finite element method for elastoimpact contact structures with translational and rotational motions. At first, the virtual work principles and their subsidiary contact conditions for the two bodies are two-dimensionally formulated in the basic contact and separate states of the two bodies, based on the conventional principle for a body. In the separate state of the two bodies, the virtual work principle and its subsidiary conditions are obtained by introducing a relative movement corresponding to clearance and regarding the bodies as a connective body. The relative movement in a slip direction is applied to the subsidiary conditions of a slip state in the same way as to the subsidiary conditions of the separate state Finally, the virtual work principles and their subsidiary conditions for the two bodies are three-dimensionally established on the basis of the two-dimensional principles and their subsidiary conditions.

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This paper is the third part of our visco-plastic and large deformation analysis by the finite element method. Algorithm to be used in this study was investigated. As the result, fundamental equations of this study were expressed by Newmark β(1/4) method. Visco-plastic matrix of constitutive equations was reformed. The result of calculation was compared with the experiment. The dynamic characteristics of collapsing of a beam were investigated. The experimental values were shown to be in good agreement with the theoretical results. Thus, this method was found appropriate and useful to deal with this kind of problems.

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A thin liquid film flowing concurrently with an air stream was investigated with regard to waves generated when superficial velocity of air was less than about 10 m/s and water flow rate was considerably low. It was made clear theoretically and verified by an experiment that a special wave, named viscous wave by the authors, is generated on the thin liquid film when film thickness was less than a definite value which depended on liquid properties, i.e., 0.255 mm at 20°C for water. Theory shows that the occurrence of a viscous wave depends more on liquid viscosity than on surface tension, and that the wave velocity is lower than liquid surface velocity. The viscous wave occurs always in the vicinity of the nonwetting region, signifying that the occurrence of it reduces the minimum film thickness, which causes a breakdown of liquid film.

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Development of time mean quantities and Reynolds sresses in a two-dimensional straight channel was measured under various inlet disturbance conditionns and decay process of both time mean and turbulence fields was examined. The decay of disturbance of time mean quantities occurs much faster than those of turbulence. Change of the Reynolds stresses in the wall region is especially slow and it requires more than seventy channel widths to attain the fully developed conditions. Development is not monotonic but has an overshooting characteristic. The Reynolds stresses normalized by the local kinetic energy of turbulence are found nearly uniform over a wide region of the test channel.

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A computer-aided data reduction method was newly developed for determining principal flow parameters on disturbance wave and liquid film in gas-liquid two-phase annular flow. Hold-up data on magnetic tape were processed by computer to discriminate disturbance wave from base-film based on the proposed criteria and to evaluate flow parameters with sub-stantial reduction of time and labor. Four test tubes of 8, 12, 18 and 26 mm bore were employed, and time-varying liquid hold-up was recorded by means of the constant-current method. The flow parameters computed were velocity, frequency, separation distance and height of disturbance waves, base-film thickness, and superficial film thickness. It was found that most of the flow parameters present a maximum or minimum with the tube of 12 mm bore.

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The pressure distribution was measured in a rotating open radial impeller under several air-water two-phase flow conditions, through narrow openings drilled on the casing shown in Fig. 1 . In order to make the pressure accurate, the most reasonable values were first selected for the pump speeds and the running clearance Sc between the casing wall and the open end of impeller blades, and then the void effects on the pressure distribution were discussed for the bubbly flow regime. At a certain void fraction, remarkable changes were observed in the pressure distributions, especially in the inlet region, so that the pump performance might change correspondingly.

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On the balance and the startup of a cylindrical capsule in the rising flow of an inclined pipe, an experimental investigation was carried out in wide ranges of several relevant factors. And it was shown that the balance state of the capsule in the pipe flow could be classified into two major states - an adhesive stationary one and a floating stationary one and that the transition between the state was characterized by a critical (inclination) angle. Next, the balance velocity of capsule and the additional loss due to capsule were discussed and an experimental formula for the balance velocity and two expressions for the additional loss factor were proposed in the adhesive stationary state of the capsule balance. Besides, on the basis of the characterizations for several factors, we present how to estimate the incipient velocity and the power required at incipience in the capsule pipeline.

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Some characteristics of flow pattern and local heat transfer past a circular cylindrical cavity in a turbulent boundary layer on a flat plate have been studied changing the cavity shape H/D=0.1∼1.0(H : cavity height, D : cavity diameter) in the range of Re=4.1×10⁴∼1.1×10⁵. It is made clear that there are two unstable flow behaviors, that is, flapping flow and switching flow, and that the additional pressure drag and the average heat transfer coefficients on the side wall and the bottom surface show a maximum value in the case of H/D=O.5, and then in this cavity, a slant recirculating eddy is formed and this flow behavior is assymmetric.

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The effects of fuel volatility on the blow-off limit and the flame stability in spray combustion were discussed. The fuels used were gasoline, kerosene, heavy oil and C heavy oil. Every spray from an air blast atomizer used in this experiment had the same initial thrust and also had the same mean droplet diameter. The axial temperature distributions on the flame center line at the condition with and without swirl were measured. For all fuels used in this report, the fuel flow rate of blow-off limit decreased with an increasing swirl strength. At weak swirl, the fuel volatility had higher effect on the blow-off limit than at strong swirl where the recirculation zone had a higher effect on flame stability, the maximum temperature gradient decreased and the peak temperature position shifted downstream.

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The Vertical downward spread of flame along a cylinder made of paper, placed in the atmosphere was investigated. The purposes of this study are to correlate the flame spread rate with the diameter, and to clarify the effect of shape of a thin combustible solid on the flame spread rate. With the other conditions the same, the flame spread rate increases with the diameter, and at the inner diameter over 10 mm it becomes greater than that of a single sheet of plain paper. A simple model for the analysis of heat transfer was employed to explain the experimental results. The theoretical flame spread rates predicted from the model were in good agreement with the experimental results. It is concluded from the experimental and theoretical results that the radiative heat transfer from the ember and the flame inside the cylinder plays an important role in increasing the flame spread rate with the diameter.

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In combustion research, optical signals from laser Doppler anemometry are often too weak compared to the flame luminosity for classical detection methods. This paper describes the photoelectron correlation method for detecting and processing such weak signals. First, a high-speed digital correlator up to a clock speed of 50 MHz has been devised, and a procedure to determine mean velocity, turbulence intensity, and probability density function of velocity has been established. It is shown that this method is applicable to measurement of flow velocities in a luminous diffusion flame. In a sooting flame, self-produced soot particles can be used as the scatterer, and this may alleviate restrictions imposed on tracer particles. It is suggested that the velocity probability density function by maximum entropy method yields information about intermittency in the flow. Finally, as an example, the flow field in an acetylene jet flame is given.

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In this paper, the vibrations of a combined system of a circular cylindrical shell with variable thickness of which one end is clamped and the other is connected to a circular plate with variable thickness are analyzed by means of the improved thick plate and shell theories. The Lagrangian of the combined system is expressed by quadratic forms of boundary values, and the frequency equations can be obtained from the minimum conditions of that Lagrangian with respect to unknown boundary values. Effects of a circular plate and some parameters such as variations of thickness upon natural frequencies of the combined system are clarified in discussions of numerical results. Transfer phenomena of the mode shapes are also investigated.

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Assuming linearized coefficients of oil film, impact response analyses of rotor-bearing system subjected to an arbitrary excitation of pedestals were made and an experiment was executed. The analyzed characteristics were in good agreement with experimental ones, in reference to two eigen values with different whirl directions and impact response by the forces generated on the exciting table. Though the non-linearity of oil film is expected in the case of steady state response by the force such as the rotor unbalance, the linearity of impact response is retained up to a considerably large amplitude of rotor.

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An investigation was undertaken with a view to establishing a procedure for diagnosing defects in rolling bearings from their vibration and sound. In the present investigation the sound of a rolling bearing with one dent in the race surface of the inner or outer ring or in the ball surface was studied. When the inner ring was rotated at a constant speed under a given thrust load applied to the outer ring, the sound occurring in three directions, i.e., radial, 45° and frontal was measured by a condenser microphone. Using the output so obtained, sound waveforms were observed, real time frequency analysis of the sound was done using Fast Fourier Transform analyzer, and the microphone position effects on the sound, etc. were examined. As a result, the fundamental characteristics of the sound of ball bearings having one dent were clarified, and a method by which to locate the defect and determine its size was established.

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To confirm the reliability of the approximation formulae for tooth fillet stresses of thin-rimmed gears (5) and to reveal the influences of many factors on the stress value, the tooth fillet and root stresses of a thin-rimmed gear calculated by the approximation formulae have been compared with the FEM calculated values : The influences of the radius of curvature of tooth fillet, of the width of the bottom of tooth space, of the pressure angle and of the loading position on tooth flank on the tooth fillet and root stress distribution for the case of a rack have been investigated and the scope of validity for the approximation formulae has been indicated. The calculation of the fillet and rootstresses for the loaded and unloaded teeth under a single and double tooth pair meshing was worked out by use of the approximation formulae, and the accuracy of calculation has been confirmed to be as good as that of FEM.

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In this report, effect of roller width on surface durability and surface failure of tufftrided and thermally refined rollers is elucidated experimentally by sliding-rolling contact fatigue tests of both rollers having roller widths of 5, 10 and 15 mm, and the experimental results are discussed with amplitude A of ratio of stress to hardness. It is recognized from Pmax^-N and Amax^-N curves that the surface durability and fatigue life of both rollers tend to decrease as the roller width increases. The surface failure mode is not influenced by the roller width in both rollers.

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This study was carried out to apply fiber reinforced metal to general-purpose machine parts, resulting in a successful large-scale production of machine parts made of devitroceramic fiber reinforced aluminum alloy by the use of the conventional die casting facility and in clarification of necessary production conditions. Mechanical tests were then performed for fiber reinforced metals themselves and hybrid composites, and it was made clear that their tensile strength at elevated temperatures, wear resistance and damping characteristics were better than those of matrix metals, suggesting the applicability of the composite materials to special-duty machine parts.

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This paper deals with a facility location problem in multiple-item small-quantity production where the production process is so selected as to minimize the travel distances of men and objects between facilities. It considers the problem of a man-machine system where the travel distance between production processes resulting from movements of object of production must be minimized. Using the idea of graph theory, it shows how to select the candidate locations for facilities and assign the facilities to these places. The production process contains some probabilistic elements and selection by GERT of the optimum locations for facilities is shown using some numerical examples.

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