In the present paper, X-ray elastic constant of metals having a texture is calculated numerically from the distributions of axis densities. On the basis of these results, the practical application of X-ray stress measurement to these metals is discussed. The calculation is made for a hot rolled steel sheet being in the state of uniaxial elastic deformation, and the results are compared with the experimental ones. As a result, the influence of texture on X-ray elastic constant was clarified and the experimental values of X-ray elastic constant were sufficiently evaluated from the present calculation. When the stress in metals having a texture is calculated by using an X-ray elastic constant determined from the axis distributions for them, X-ray stress measurement has satisfactory accuracy, but the elastic constant obtained without considering the texture introduces some error into the stress measurement.

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Stress-strain relations of commercialized metal in reloading in various directions after axial and torsional preloadings of various sequences and magnitudes are superimposed, are experimentally investigated. Experimental results are put in order on the basis of a double surface hardening model which consists of elastic, transitional hardening and steady hardening regions. Utility of the double surface theory for describing the complex plastic deformation behavior of metal is confirmed under combined stress conditions. It is also confirmed that the effect of the past deformation history on plastic properties of metal can not perfectly be liquidated in general by any following loadings. Effective stress-strain relation in the transitional hardening region, which is represented in non-dimensional expressions, can be shown by a specific expression without regard to material and prestrain history. Many other significant conclusions are obtained.

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We have theoretically calculated the coefficient of permeability of an assembly of spheres wetted with residual fluid which does not mix with the flowing fluid. The method used is based on a double-cell model, which is an extension of the improved cell model. The results are compared with those obtained from experiments using kerosene, spindle oil and water, and the applicability of the theory is discussed. It is found that the permeability constant is influenced by the ratio of the viscosity of the main stream to that of the remaining fluid. When this ratio exceeds 1.5, the remaining fluid acts as a lubricant, making the main fluid flow easier.

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This paper describes the transmission loss characteristics and acoustical overall performance of expansion-chamber silencers with tapered connectors at either end or both ends of the chambers which are widly used in ventilation systems. The transmission-loss equations for these silencers were derived by using plane wave and conical horn theory. The calculated results agreed fairly well with those of the experiments made at room temperature and without a flow. The values of the transmission-loss shift toward the lower frequency and diminish as the length of the tapered connectors is increased, but its maximum values in the low frequency range are similar to those of the ordinary type of expansion-chamber silencers.

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Corrugated wall channels are investigated as a means of augmenting forced-convection heat transfer with a single-phase flow in heat exchangers. The fluid flow state and the heat transfer characteristic of the parallel channels bent many times, which are appropriate models of corrugated wall channels, are analyzed by the finite difference method with an adequate "periodic boundary condition" for the laminar flow where the pitch P=1∼8, the bending angle θ=0°∼90° and Reynolds number Re=0∼2400, and for the turbulent flow where P=1∼8, θ=90° and Re=40000. Consequently, the effects of P and θ on the aspect of flow, the distributions of the wall shear stresses and the local Nusselt numbers, the pressure loss and the mean Nusselt number are clarified, and the performance of the corrugated wall channels as heat exchangers is estimated in terms of the volume goodness factor.

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The local heat transfer rate around a heated, horizontally vibrating cylinder is measured, and the thermal profile, close to the cylinder surface, is obtained by a Mach -Zender interferometer. Moreover, above and below the cylinder, the velocity and thermal profiles of the upward stream of natural convection are measured by a hot-wire anemometer and a unit of temperature-measurement, and then the change in the flow pattern of natural convection is examined by a flow visualization method, using smoke. As a result, the cause of change in the local and the mean heat transfer rate of a heated, horizontally vibrating cylinder is clarified.

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Aquifer Thermal Energy Storage (ATES) is very promising in such districts where seasonal variance in climate is significant and aquifer exists abundantly, for example in Japan. Regional flow, however, is feared to disturb the favorable recovery. In this paper, influences of regional flow on ATES are investigated analytically. Method for selection of appropriate location of wells under the existence of uniform regional flow and its application to practical ATES are discussed. It is concluded that mean recovery temperature of 50% is obtainable.

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In order to investigate the quenching distance determined by the flanged electrode method, behaviors of flame propagation between two parallel flanged disks are observed by use of high speed motion schlieren photographs and ionization probes. It has been shown that there are four kinds of the flame propagation behavior and that the transition regions exist between different behaviors. Based on this observation a new method for determination of the quenching distance is proposed. Further, the influences of diameter of the flanged disks on the value of quenching distance are discussed.

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This paper discusses how to make a simulation of the gas exchange process in a small two-stroke cycle engine where the treatment is planned for the following factors. Namely, (1) diffusion factor in the scavenging passage, (2) mixing factor in the scavenging passage or the crank case, and (3) mixing factor and short-circuit factor in the cylinder. The simulation with suitablly selected factors willenable the scavenging performance of the actual engine to be grasped. Then, in addition to the above, a three dimensional indication of the flow-gas component clarifies the flow considering the blow-back and return-blow in the scavenging passage. The simulation calculation is balanced by setting supplement enthalpy for the material motion of the gas in the pipe system. The calculation is made by the method of characteristics or FLIC method in the pipe system, and of stairc method in the cylinder.

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This paper deals with a widely applicable simulation of the gas exchange process in a small two-stroke cycle gasoline engine. Theoretical result shown by the 1st report was compared with the experimental data obtained from pressure and gas analysis under various cylinder port heights and engine speeds. In this simulation, the diffusion factor ε_m in the scavenging passage, the mixing factor r in the scavenging passage or the crank case, and the mixing factor ψ_m and the short-circuit factor ψ_d in a cylinder, are taken as follows : For the exhaust lead of 0.026∼0.184 and the engine speed of 1000∼5000 rpm, 0 ≨ ε_m ≨ 0.08, 0r ≨ 0.35 (in the case of return-blow), 0 ≨ r ≨ 0.06 (in the case of blow-back), 0.7 ≨ ψ_m ≨ 1, 0 ≨ ψ_d ≨ 0.1. The optimum values of the scavenging efficiency and the charging efficiency are obtained at the exhaust lead of 0.096 and engine speed of 2800 rpm, ε_m=0. 01, r=0. 01 (in the case of return- blow), r=0 (in the case of blow-back), ψ_m= 0.85, ψ_d=0.

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This paper clarifies the characteristics of responses of flexible rotor systems with arbitrarily distributed mass passing through many critical speeds sequencially using numerical solutions obtained from the transition matrix method. The solutions superposed of each mode using these approximate equations coincided with numerical solutions very finely. Therefore, the total behaviors of the vibration of the shaft or the maximum amplitudes not only in passing through a single critical speed but also in passing through many critical speeds can be estimated by these approximate equations. It is made clear that the maximum amplitudes in transition through each critical speed are not influenced by the starting point of accelerations and they are close to those in the accelerated cases from the state of non-rotation.

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Regarding gyroscopic effects, approximate equations of the responses in passing through critical speeds for distributed mass rotor systems on isotropic or anisotropic supports are derived by an asymptotic method. In the case of flexible rotors on anisotropic supports, the nonstationary vibration in passing through two neighboring critical speeds are computed and the coupling phenomena are discussed. Further, the whirling directions in transient vibrations of a fundamental rotor on anisotropic supports are made clear by numerical solutions.

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The behaviour of the sound radiation from the plates of a housing being excited with each mode frequency has been studied theoretically and experimentally from a view point of directivity and by means of acoustical holography. The directivity is theoretically determined from the relation between the bending wavelength of a plate (λ_pt) and the sound wavelength in air (λ_air) by the use of the lattice mode of monopole sound sources. When λ_pt/λ_air is smaller than 1.0, the sound is radiated along the plate and the acoustic power is reduced. And the reported images of acoustical holography have been explained with the directivity of sound depending on λ_pt/λ_air.

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There are various isolators made of springs or rubber for portable vibrating tools. Most of them, however, have not been always effective in vibration reduction of tools. Even though an isolator consisting of conventional undamped absorbers was introduced, It also proved to be ineffective because of the fluctuation of operating frequency. Consequently, a feedback controller was adapted for keeping a constant operating frequency and, moreover, a compound dynamic absorber was developed. Its absorber consists of several "parallel" nominally undamped absorbers with appropriate dispersion of their natural frequencies. Then the attributes of the compound absorber were analyzed and it was confirmed that a frequency bandwidth of its transmissibility was spread over a wider area than the conventional one's. In the experiments, the excellent performance of compound absorber in reducing vibrations fluctuated at the frequency range of controller was verified.

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Many investigations have been hitherto reported as to the stress caused in coil springs. All of them, however, didn't take pitch angle or torsion of coil into consideration precisely. The authors have formulated, from Wittrick's formula, an analytical method applicable to coil springs with a large pitch angle and also confirmed its validity by experiments. The authors' investigation treated a case where the maximum principal stress occurs, contrary to the traditional concepts, at the surface of outer coil of spring.

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A study on the load-carrying capacities of carburizing hardened gears made of leaded free-cutting steel is carried out with power-circulating gear test rigs. In this paper, we examined the problem on how the differences between the mechanical properties of carburizing hardened gears made of normal steel and leaded free-cutting steel affect the life for pitting and the scoring resistance of the gears. From the experimental results of the pitting and the scoring tests it was made clear that the life for pitting of the hardened gears made of normal steel is approximately two times larger than that of leaded free-cutting steel . On the other hand, the scoring resistance of the hardened gears made of normal steel is slightly smaller than that of leaded free-cutting steel.

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In this report, the transmission error of toothed belt drives under a state of applied initial belt tension in the static region is experimentally and theoretically discussed. A measuring instrument for transmission error of toothed belt drives using a micro-computer system was made by way of experiment. It was confirmed that : (1) A transmission error was generated by the difference of tension between both sides of belt caused by the interference between belt teeth and pulley teeth at an incomplete meshing region. (2) The period of the transmission error coincided with the pulley pitch. (3) The amplitude of the transmission error was affected by the initial belt tension and the phase angle. The calculated results of the transmission error agreed with the experimental results.

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Authors have carried out running tests of hobbed spur gears, measuring the dynamic root strain and the electrical resistance between meshing teeth. Compared with the case of integral gear ratio (1/1) where elastohydrodynamic films grow rapidly built up during running owing to an improvement of conformity between micro-geometries of meshing teeth, it is verified, in the case of hunting gear ratio (27/25), EHD film is hard to build up since severe asperity contacts repeatedly take place due to the replacement of meshing teeth. Therefore, surface durabi1ity for pitting in hunting gear ratio becomes considerably lower than in integral one. It is also shown that the state of EHD film formation and durability for pitting in hunting gear ratio are noticeably affected by combinations of gear materials and by surface roller finishing by which asperities of the tooth flanks are depressed.

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For easy manufacture of internal gear pumps, an internal gear with a convex tooth profile and an external gear, of which tooth-top edge contacts with the convex profile, are used for the gear pumps. Gearing theory of these gears and the theoretical delivery of the internal gear pumps with these gears are clarified. The prominent characteristic found in the gear pumps is that the theoretical torque caused by delivery pressure is zero for the external gear (idler). In practice, a small value of the resistance torque appears on the idler due to viscous friction, etc. It is shown that the resistance torque has no detrimental effects on the tooth surface up to a delivery pressure of about 2 MPa in the present experiments because the Hertzian contact pressure is less than the allowable contact stress of a low hardness steel when the tooth-top edge is rounded to a radius of about 0.5 mm. Six kinds of gear pumps were designed and made by the authors, and almost all characteristics of these gear pumps were clarified by experiments with the support of the theoretical results obtained in the present investigation.

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