This paper considers the influence of interference between disk and hole on the stress and displacement distributions around a circular hole. which is filled with a smooth elastic disk, in an infinite elastic plate under uniaxial uniform tensile or compressive loading. The contact radial stress between disk and hole is expressed with absolute convergent series, whose differential form is also convergent. The stress and displacement are numerically analyzed by the point matching method. Numerical results are presented for various combinations of sizes and moduli of plate and disk. The main results are as follows: (1) The contact region and stress distribution of plate are independent of the magnitude of uniaxial loading, when diameters of disk and hole are initially the same. (2) When diameters of them are not the same, the contact region and stress distribution of plate vary with a change in magnitude of loading.

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Applying combined tensile and torsional stresses to a thin-walled tube of softened celluloid, creep deformations of the material were investigated experimentally under stress states along stress trajectory with a rectangular corner together with those in the relation of mirror transformation, or under cyclic torsional stresses. Main features revealed may be summarized as follows: (I) It was found that (1) the hardening behavior of the material appeared during the creep deformation under constant stress, (2) the softening behavior occurred in the early period after the corner of the stress trajectory and stress reversal, and (3) the hardening behavior grew with cyclic stress reversal. (II) It was ascertained that the creep deformation behavior was expressed well with use of the viscous-viscoelastic theory including a little disagreement in the cyclic hardening behavior due to stress reversal.

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Elastic follow-up has been one of the important items in designing structures for high temperature use. It involves still many problems not yet fully investigated. The ASME Code Case N-47 states that the secondary stress with a large amount of elastic follow-up shall be classified in load-controlled quantities, and any stress with elastic follow-up should be included as primary stresses for the purpose of strain limit evaluation. However, it does not indicate how to specify the elastic follow-up as large or not. The present paper describes experiments and comparisons with theories on uniaxial elastic follow-up behaviors. The theories which have been proposed to evaluate the elastic follow-up behavior consist of several simplified inelastic analyses. It has verified that the inelastic analysis based on Norton's law was in much better agreement with experiments than the analyses by the stress partition method or the magnified secondary stress method.

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The T. N. P. method (Translation of Nodal Points method) is applied to the three dimensional crack growth analysis. The method is compared with the conventional one for two dimesnionalproblem and good agreement is recognized. CT specimens with and without side groove are anlayzed in elastic and elastic-plastic states. It is shown that the crack grows and equalizes the J integral distribution along the crack front. The resultant crack front configurations agree with those obtained in many experiments.

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The objective of this study is to propose a practical method to evaluate the fracture resistance of a stably growing crack by crack energy density and to verify it through its applications to actual stable crack growth problems. The contents of this report are as follows: (1) More refined investigation of the relationship obtained before between initial crack length, present crack length, load-diplacement curves and the additional rate of crack energy density which holds until a crack starts to grow is made by using two crack models. (2) A relationship between initial crack length, present crack length, load-displacement curves and the additional rate of crack energy density caused by using the same crack models as sued in (1). (3) A method to evaluate the fracture resistance of a stably growing crack from load-displacement curves which can be easily obtained by experiments is proposed, based on the relations above.

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The method proposed in the 1st Report for evaluating the evaluating the fracture resistance of a stably growing crack by crack energy density is applied to the stable crack growth problems of thin plates, and its applicability and validity are confirmed. Experiments of stable growth fractures are carried out for thin single-edge cracked specimens with different initial crack lengths under tensile force. The fracture resistances expressed by additional rates of crack energy density and crack energy density are evaluated, based on the results. When fracture modes are almost the same, fracture resistances have almost the same values regardless of initial crack lengths, and their values vary only corresponding to he change of fracture mode caused by crack extension. The difference of specimen types has no influence either on their values.

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This paper shows how an impact contact force can be expressed as a product series of penalty functions and subsidiary contact conditions having relative movement components between two bodies on a contact surface. A penalty function type of virtual work principle for various contact and separate states of two bodies is formulated by using the expression of the impact force. This principle is most effective for solving a general impact response of the alternation between contact and separation, and a stress wave propagation response of cracked structures with open and/or closed states on a cracked surface, because of both the use of the relative components and the relaxation of all the subsidiary conditions in this principle. A finite element method (FEM) based on this principle is applied to a two-dimensional analysis for longitudinal impact of two uniform rods. The mean value of impact force by FEM results coincides well with the value from the theory of one-dimensional elastic stress wave propagation.

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An approximate factorization code has been developed for analyzing transonic cascade flows. In this scheme, upwind differencing is used for introducing artificial viscosity in the supersonic region, and central differencing in the subsonic region. The resulting simple two- and three-banded matrices are solved by the relaxation procedure. In this paper, the efficiency of this scheme is demonstrated by solving a channel flow problem, and then this scheme is applied to some cascade flows. The results are in good agreement with those obtained by other methods.

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This paper considered a flow normal to an infinite thin elliptic cylinder which is uniformly accelerated from rest in a direction perpendicular to its generating lines in a viscous fluid. The Dufort-Frankel method for vorticity transport equation is used for the numerical simulation of viscous incompressible flows, and a new finite Fourier transform method is introduced in order to handle the stream function equation for accurate and efficient calculation. A major part of the present paper is devoted to physical properties of the flow during the early stages of wake developement behind an obstacle, for a Reynolds number of 98.11. A computer-aided flow visualization technique is used to demonstrate the main features of the hydrodynamic field for the flow. The rest of this paper demonstrates the important unsteady forces such as time-dependent drag, lift and moment acting on a body immersed in a viscous fluid, and presents specific numerical results for various transitions.

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Transient response to a sudden change in pressure or flow rate in tapered fluid line is theoretically studied. Response solutions are derived for two types of inputs, a step input and an impulse input, by using both open-end and closed-end as a line condition. A fundamental equation employed in this analysis is based on a fluid line model in which the frequency-dependent effects of viscosity are taken into consideration. It is confirmed that the theoretical results well agree with the ones obtained by numerical calculation by the method of characteristics with various system parameters.

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An experimental study has been made on the flow of viscoelastic liquids in thin films held between a flat plate and a spherical surface of a large radius of curvature. In particular, the case is investigated when a spherical surface begins to roll on a flat plate from stationary and contacting state. Dilute polymer solutions are used as viscoelastic fluids, whose properties are elastic but Newtonian in viscosity. Compared with non-elastic liquids, some effects are shown: The point of cavitation is far from the center of contact where the thickness of the liquid film is minimum. The thickness of the liquid film, generated with rolling movement, is larger than that of non-elastic liquids.

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In this paper, electrostatic drop formation characteristics in the use of water-based ink are reported for applications to ink jet devices. In order to make clear experimentally the electrostatic uniform drop formation phenomenon, applied voltage, flow rate, nozzle diameter and distance between the nozzle tip and the electrode are widely varied. In addition, liquids having different values of electric conductivity, surface tension and viscosity are used, and the experiments are carried out to examine the effects of these factors on the uniform drop formation. Then, the relations among the various factors governing the uniform drop formation phenomenon are studied by a dimensional analysis.

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Water hammer phenomena caused by a sudden valve closure are investigated in one-component two-phase flows. The phenomena in one-component two-phase flows are more complicated than those in two-component two-phase flows because of the presence of mass transfer between liquid and vapor. Basic partial differential epuations based on a one-dimensional homogeneous flow model are solved analytically by linearization and iterated Laplace transformation. The profile of the pressure transients at the closing valve are given. It is shown that the mass transfer between the two phases has a great influence on the profile of the pressure transients, and that the magnitude of the influence depends on the relaxation time τ_M of the interphase mass transfer.

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A steady fully-developed laminar flow of power-law fluids through curved pipes has been solved numerically under Dean numbers D ≲ 1000, power-indices n=1∼0.5 and curvature radius ratios Rc=10∼100. Velocity profiles of a primary flow, stream lines of a secondary flow, distributions of wall shear stresses and friction factors are obtained. Effects of D, n and Rc upon flow characteristics are made clear.

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A steady fully-developed laminar flow of power-law fluids in curved pipes has been analyzed using boundary layer approximations in order to obtain the friction factor for high Dean numbers. Experimental results for the friction factor are compared with the analytical results. Also, a flow in curved pipes of elliptic cross section has been investingated experimentally.

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Stability analysis for the occurrence of Taylor-Gortler vortices in turbulent wall jets along concave surfaces is made in a comparative experiment. The eddy viscosity expression in the perturbation equations is derived from a modified version of a two-equation in the perturbation equations is derived from a modified version of a two-equation turbulence model including curvature, which predicts well the main features of the turbulent wall jets along concave surfaces. Through the stability analysis, it is found that the minimum curvature at the neutral stability state decreases slighly as the Reynolds number increases. Then, the eddy viscosity expression is treated as a function of curvature.

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The authors have reported that the two-dimensional Karman vortices behind a circular cylinder with diameter d are broken into lengths of about 8d and they form chains of spoon-shaped vortex couples. In the present experiment disks were attached to the cylinder so that the Karman vortices were artificially cut to fixed lengths of 4d, 6d, 8d and 10d. The structures with 8d were most stable forming a vortex chain with least irregularities and the wake was much wider than without the disks, while the neighbouring vortices with a length 4d merged to a scale of 8d, These results show that the length 8d is a unique scale in the deformation of the Karman vortices to a three-dimensional large scale structure.

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An image processing method for the analysis of a turbulent structure was devised. It was applied to an impulsively started axisymmetrical jet growing into an otherwise quiescent fluid. The development of the statistical average contour and the growing behaviour of the jet were clarified. Simultaneous measurements of the concentration and the velocity at a fixed position were carried out and the transient phenomenon at the position was made clear. By comparing the results of the two methods, the average behaviour and the characteristics of the turbulence of the jet were revealed. It is confirmed that the image processing method developed here is effective for the analysis of the spatial structure of turbulence in an unsteady flow field.

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This paper presents the theoretical and experimental results obtained by a study of eccentric cylindrical capsule transportation. The flow in the annular section of a capsule can be approximated by a flow through annular pipes when the inner pipe moves. A general formula for the pressure loss due to friction drag in a turbulent flow through stationary eccentric annuli is derived by applying the idea of the one-seventh power law for axial velocity distribution and a rational model of eccentricity. Furthermore, by applying the results obtained in the study of a concentric capsule flow, the formula is developed for the flow in the moving eccentric annuli. Then in the experimental part of this study, the validity of the formula is confirmed. And the capsule velocity, as well as the total pressure loss which is caused by friction drag and pressure drag, is estimated with reasonable accuracy.

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Concerning a vertical type latent heat TES (thermal energy storage) capsule having the vertical axis, experiments and analyses were performed to discuss the heat transfer mechanisms in the heat storage process. The time dependency of the local heat flux across the capsule wall was measured and the natural convection flow within the capsule was observed, varying the height of the phase change material (PCM). The finite difference analyses considering the natural convection flow were also done. As the result, it was shown that the rate of the heat storage increased with a decreasing capsule height, because the melted liquid PCM with high temperature stagnated in the upper part of the capsule by stratification.

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Negentropy should be defined by Kullback-Leibler information in a general situation, not by the difference of entropies nor by minus the entropy. In the present report, the formula of the negentropy defined by Kullback-Leibler information is expanded into some terms from two different viewpoints. Of the two expansions of this formula, one is done if accordance with the change of circumstances to which the system is exposed. The cross term of negentropy is derived from this expansion, and it represents the negentropy which is taken out of the system by replacing circumstances. The cross term of negentropy does not appear unless negentropy is defined by Kullback-Leibler information. The other expansion of the negentropy defined by Kullback-Leibler information is done in accordance with the division of a system into two subsystems. The mutual negentropy is derived from this expansion, and it represents the nonequilibrium between the two subsystems.

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In this report, a mathematical model for expressing three-dimensional development of a laminar flame in a closed vessel has been proposed, and a numerical calculation method, which the author termed a space difference one, is derived. This makes it possible to evaluate the changes of properties, such as burning time, flame volume, flame- and flammable-surface area, mass burning rate, and mass burnt fraction, and to illustrate the three-dimensionally expanding flame. The characteristics of this method are also examined. Using a cylindrical vessel and a stoichiometric propane/air mixture, the effects of the location of ignition points on the changing processes of those properties are evaluated.

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The flame at the top of a burner enters the burner channel when a mixture is stopped quickly. The quenching distance measured by a burner method means the minimum width of the channel through which the flame can pass. The problems about three measurement methods are discussed with optical observation in this paper, and it is found that a tapering burner method is the most recommendable of these measurement methods are discussed with optical observation in this paper, and it is found that a tapering burner method is the most recommendable of these methods for the following reasons. When the mixture is not spark-ignited but the flame is held at the top of the burner, method with spark ignition, abrupt change of cross-sectional area of the flame entrance often prevents the flame from entering the channel. At that time, the flame does not interact with the surface of the channel. The above defects are eliminated in the tapering burner method with spark ignition.

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Combustion impact is one of the most predominant sources of engine noise. The transmission-radiation coefficients of combustion noise, which were defined as a conversion power ratio from the combustion impact to the emitted noise, were studied with both a stationary engine excited by a single explosion and an operating engine. The characteristics of these coefficients obtained in the same engine coincided with each other, so it can be said that the transmission and radiation of combustion noise of an operating engine are analogous with those of a stationary engine, to a certain extent. Then, the vibration response for combustion impact and the noise radiation coefficients were examined for each engine wall to identify their contribution to the total combustion noise.

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An analytical solution of the forced tortional vibration of a two degrees of freedom system with a clearance between two rotating bodies is derived. The analytical solution is obtained by connecting the solutions for the motion of each body caused by successive collisions of the bodies, without making assumptions on the number of times of collisions that occur during a cycle of the forced motion and on the periodicity of the collisions. The analytical solution shows the existence of a phenomenon of multi-time collisions at one side of the clearance during a half cycle of the forced motion. Effects of the dimension of the clearance and the average angular velocity on the strength of the impact force are investigated. The results of the analytical solution show good quantitative agreements with those of the simulation.

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This report presents a load combination methodology for dynamic response analysis problems, based on a stochastic approach which has been practically introduced in the field of random vibration theory. The methodology proposed in this report has the advantageous point that the appropriate correlation effect among combined load compoents is take into consideration and is evaluated in terms of the dynamic correlation factor p. The specific combination problem discussed here is the calculation of the maximum base shear coefficient of a large-scale cylindrical liquid storage tank which can be simulated by a simplified lumped mass model, whereby the sloshing effect of the liquid is neglected. It is concluded that the equations of combination constructed here are applicable for the case where the fundamental natural frequency of input acceleration such as seismic ground excitation; while an equation proposed in a previous report is effective for other cases. The accuracy of this method is statistically examined by use of the random vibration technique; and its advantage over SRSS (square root of sum of squares) law and ABS (absolute value summation) law is examined with the aid of the numerical computation of practical examples.

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A comprehensive expression of solutions is obtained for the ball passage vibration (running accuracy) problem of a ball bearing which is loaded in a radial direction and rotated slowly. The results offer the general relation between characteristics of the vibration (Fourier coefficients, peak to peak amplitudes, distortion of wave form) and dominant factors (specification of the bearing, radial clearance, and the load). A procedure is proposed to evaluate the relation between the clearance, load, and amplitudes in actual dimensions, using the chart of general expression.

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Forestry workers who use the chain saw, daily in their works are susceptible to vascular disease disorders of the fingers and hands, due to exposure to the severe vibration. This paper presents the structure, design, dynamics of machinery and numerical computation of the equivalent moment of inertia and loads acting on each portion of a new vibrationless chain saw. The perfect balance for this chain saw engine utilizing internal gearing system are theoretically analysed. The dynamic analyses of moving parts in this chain saw engine are explained. The output torque consists of gas pressure torque, minues the friction loss torque and inertia torque resulting from unevenness of rotation. The equation for output torque is the same as that or a conventional chain saw. However, the equivalent moment of inertia acting on the crankshaft is constant, regardless of crack angle, and is about 10 percent larger than that for a convential chain saw. The values of the moment of inertia, load conditions on each portion and the tooth force are obtained by numerical computations.

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This paper presents performances characteristics of a new type vibrationless chain saw having a perfectly balanced rotation-reciprocation internaly gear device. Vibration, and noise levels, output power and fuel consumption during timber cutting and racing conditions are given. And then they are compared with values for a conventional chain saw of similar engine displacement. The vibration levels of this chain saw are very low in comparison with those of the convential chain saw and are below the tolerance limits for occurrence of vibration injury in work with a chain saw in many countries. It is therefore considered that this chain saw is highly practical and useful for the improvement of the vibration circumstances. However, the brake horsepower is lower than for a conventional chain saw. This situation could be improved by reducing the empty volume of crankcace.

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The forced nonlinear vibrations of simple beams supported with two kinds of ball screw type dampers are discussed both numerically and experimentally. The dampers are composed of a ball screw, a flywheel and flyball or perpendicular type governor, and they possess nonlinear characteristics. The beam is replaced by a lumped mass system and the Continuous System Simulation Language is used to simulate the motion of the masses and the damper on a digital computer. The results may be summarized as follows: (1) Two types of dampers are effective for suppressing the amplitude of the beam at the point of attachment of the damper at the first resonance. (2) The linear solution which is obtained by regarding the governor as a flywheel differs from the nonlinear solution in the vicinity of the first resonance frequency of the beam. (3) Each damper approaches the snubber for larger values of moment of inertia J of the flywheel, and acts like a dynamic vibration absorber for smaller values of J.

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The behavior of a truck crane equipped with a telescopic box jib during load hoisting and fib hoisting is numerically analyzed on the basis of a simulation model. To verify the analysis, experimental tests are carried out using a real crane. The theoretical results are in good agreement with the experimental data. Thus, the dynamic behavior of truck cranes with a box jib can be predicted, Effects of jib rigidity, jib inertial forces, and braking time on the behavior of such cranes are also revealed in the analysis.

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This paper presents an optimal design of primary stiffness of a conventional truck. The aim of this study is to derive an analytical equation which represents optimal stiffness for hunting stability and curving performance. Using a simple 4-degrees-of-freedom dynamic model of truck, optimal primary yaw and lateral stiffnesses are calculated for critical speed of wheelset and truck hunting as functions of various wheelset parameters and creep coefficients. The analytical method of curving performance is proposed considering the track conditions described by curve radius, flangeway clearance and cant deficiency. Introducing non-dimensional flangeway clearance, normalized unbalanced centrifugal force, bending and shearing stiffnesses, four equations are obtained. If these equations are satisfied, good curving performance can be expected. Using the results, the optimal design of conventional passenger truck for high speed operation has been discussed.

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This paper presents a new dynamic simulation method as an application of Linear Graph Theory and attempts to analyze the motion of the electromechanical hybrid system such as the transmission for engine/flywheel hybrid car. By modifying the program presented already by the authors in the 1st report, a dynamic simulation program is presented. For the purpose to shorten calculation time of this program is presented. For the purpose to shorten calculation time of this program and to treat sparse matrix algebra a new technique is introduced. The technique prepares pointer vectors and pointer matrices for both columns and row of the Tableau matrix to avoid calculation of zero elements. After those preparations, the authors present some terminal graphs and terminal equations which represent both electric and mechanical devices, such as engine, flywheel, D. C. motor, etc. By using these graphs and equations the behavior of the transmission is simulated. Comparing the simulation data with the experimental ones, it is made clear that this simulation method is useful.

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Approximate Correction Method (ACM) and Exact Correction Method (ECM) are proposed to remove the form distortion caused by the eccentricity of a measured part when estimating the roundness error on the basis of Minimum Zone concept. Numerical tests and measurements are performed using BFGS formula for optimization. As a result, it is found that ACM is a practical method from the viewpoint of both computation time and accuracy, and that ECM is an effective one for measuring roundness error with extremely high accuracy for any eccentricity although a little more time is taken.

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One of the most effective ways to realize a high speed positioning control is to decrease the weight of the mechanical parts of the system. But in such a system, flexibility must be taken into consideration in the control theory, otherwise it would result in positioning error and remaining vibration. Positioning control depends on an access mode and a positioning mode; and to realize a high speed positioning control, fast access is required at first. In the access mode, it seems to be possible to control a flexible system with an open loop circuit, so long as there exists little disturbance. From this point of view, the access mode of high speed positioning control of a flexible system with minimum input energy is discussed in this paper.

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In the present paper, the tooth deflections of internal spur gears with various numbers of teeth and addendum modification coefficients were calculated by 2-dimensional elasticity theory and mapping function. The results were compared with those by 2-dimensional finite element method (FEM) and the formula proposed by Hidaka, et al., and the validity of tooth deflection analysis of internal spur gear by the theory of elasticity was confirmed. The tooth deflections of internal spur gears due to Hertz contact calculated by the theory of elasticity were compared with those by Lundberg's and Weber's formula. Furthermore a practical formula for tooth deflection of internal spur gear was derived on the basis of these calculated results.

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In the present paper, the tooth deflections of internal spur gears with various numbers of teeth and addendum modification coefficients were calculated by 2-dimensional elasticity theory and mapping function. The results were compared with those by 2-dimensional finite element method (FEM) and the formula proposed by Hidaka, et al., and the validity of tooth deflection analysis of internal spur gear by the theory of elasticity was confirmed. The tooth deflections of internal spur gears due to Hertz contact calculated by the theory of elasticity were compared with those by Lundberg's and Weber's formula. Furthermore a practical formula for tooth deflection of internal spur gear was derived on the basis of these calculated results.

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This study reports on a method of making the fatigue design of bolted joints. Two types of bolted joins are treated - one is the simplest cylindrical joint. The following conclusions are obtained through stress analysis and fatigue tests of the above-mentioned bolted joints; (1) A method is proposed for expressing the load applied to the bolt in joints by plotting the dynamic stresses of the bolt on Haigh diagram, taking the maximum load and the preload as parameters; (2) A stress analysis of the T-flange bolts is performed. The analytical results show good agreement with the experimental results measured with strain gages; (3) It is verified by the fatigue test that fatigue design of the T-flange bolts can be done by comparing the above-mentioned load and the fatigue strength of the bolts.

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Few investigations have been carried out on the characteristics of bolted joints subjected to external bending moments. Furthermore, it seems that the characteristics of bolted joints with gaskets or filler plates subjected to external bending moments have not been studied. In this study, the characteristics of T-flanges with gaskets (filler plates) are examined. In an analysis, replacing T-flanges and gasket (filler plate) with finite strips, the contact stress distribution, the force ratio for the external bending moment (the relationship between an increment (decrement) of bolt axial force and the external bending moment) and the maximum stress produced in bolts are analyzed by using a two-dimensional theory of elasticity. For verification, experiments are performed with respect to the force ratio for the external bending moment and the maximum stress. Analytical results are in a fairly good agreement with experimental ones.

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In order to analyze the vibration of a structure whose elements are connected with bolts, it is necessary to estimate the flexural rigidity of bolted connections. But, although a few papers have reported studies of flexural rigidity, a calculation method to estimate the flexural rigidity has remained unestablished. This paper deals with a calculation method to estimate the flexural rigidity of bolted annular flange connections subjected to an external bending moment. In the analysis, models for estimating the flexural rigidity K_b of bolts, and K_f of annular flanges are proposed, taking account of the dispersiveness of bolt disposition. Thus, a calculation method for obtaining whole flexural rigidity of bolted flange connections is proposed, using the values of K_b and K_f. For verification, experiments are performed under several conditions. Calculated results are in a fairly good agreement with experimental ones.

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The present paper deals with a method to improve the stiffness of bolted joints in machine tools. In the reasonable design of bolted joints, the stiffness, the bolt axial force and the distribution of contact stresses are important characteristics to be considered, and they have been investigated by many researchers. But effects of the tightening position of screw thread in a base, the thickness of clamped parts and the configuration of contact surfaces are not taken into consideration sufficiently. Thus, in the present paper, the effects of the tightening position of screw thread in the base on the stiffness and the distribution of contact stresses are examined experimentally in the case where a beam is fastened partially to the base with tap bolts. As a result, it is shown that these effects contribute to the improvement of the stiffness of bolted joints.

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This paper deals with a boring bar used for boring operations in a speed range higher than the critical speed of the bar. One of the merits of this boring operation in a high speed range is that chatter-free machining can be theoretically obtained. In this study, it is shown that the bar must be designed to have external damping as many times as internal damping. Also, it has been proved experimentally that chatter-free operation can be realized. Another unexpected advantage is that in the experiment of boring aluminium work, chips are all broken in short lengths unlike to continuous tangly chips in conventional boring.

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Actual cases in which the output of a cut set depends on the sequence of occurrences of repairable basic events are shown in the FTA of human-robot systems. The necessity of quantification of consecutive failure logic is emphasized. Exact and approximate methods of calculating the existence probability and the expected number of occurrences of the output event are proposed. Input to the consecutive failure logic is assumed to consist of statistically independent, exponentially distributed and repairable basic events.

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