This paper is concerned with the stress distributions and the displacements arising in an infinite cylinder which is shrink-fitted to a finite hollow cylinder. The three-dimensional elastic theory and the point-matching method are used to calculate the displacements and the stresses of the infinite cylinder and the finite hollow cylinder. An individual case is worked out in which the contact is frictionless an the sufficient friction occurs to cause complete adherence between surfaces in contact. The distributions of the contact stresses and the displacements are obtained for models of various elastic moduli. These are compared with the results obtained from the two-dimensional calculation and those of the shrink-fit problem of an infinite cylinder and a flexible sleeve.

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In the previous paper, the deformation under internal pressure was analysed for a supported short cylinder of aluminum alloy as the material having non-linear stress-strain relation. On the other hand, it is well known that the mode of elastic deformation of thin cylindrical shells of finite length under internal pressure is different according to the ratio l/√(ha), where 2l, 2h and a are length, wall thickness and radius of the cylinder, repectively. Such a trend may be expected to be modified for the above mentioned material. In the present paper, a long cylinder with the same size as that mentioned above except its length was analysed in the same way as in the previous paper, in order to investigate the trend of deformation mode in such materials. As the result of analysis, it may be concluded that the mode of the long cylinder varies gradually with an increase of internal pressure and approaches that of a short cylinder, in the non-linear range of stress-strain relation.

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This paper is concerned with a problem of a simply supported column initially bent in the shape of a half sine wave and having one end axially struck by a mass directly. First, assuming the end of the column always in contact with the mass and neglecting the axial-inertia effects, the nonlinear integral equation was derived and its solutions agreed well. Second, considering that the end of the column was apart several times from the mass in one strike, authors obtained the numerical solutions, which showed good agreement with the experimental result in relation to the mid-span axial force.

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This paper treats a simply supported column with an initial deflection, which has on end struck by a mass along the axial line at higher impact velocities than in the previous study. The numerical solutions agree with the experimental results. Conclusions are as follows: (1) In the case of the high velocity impact, the column is buckled locally near the impact end. After that, this buckled region spreads towards the supported end. (2) The axial force begins to decrease rapidly by this local buckling, and later a large tensile axial force caused by the effect of unloading wave is observed near the supported end. (3) The higher the impact velocity is, the shorter the buckled wavelength becomes, and then the fracture point approaches the impact end. (4) The phenomena abovementioned are due to the influence of axial force.

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The frictional resistances on a rotating smooth plane disk in an enclosure filled with various concentrations of polymer solutions have been investigated. The data were obtained on the torque in the laminar and turbulent flows, their range extending from disk Reynolds number 2×10⁵ to 2×10⁶ and axial clearane-disk diameter from s/d=0.529 to 0.118. Instantaneous photographs were taken of the flows near the surface of the disk in Newtonian fluids and polymer solutions. As a result of these observations, it has been revealed that the radial secondary flows which accompany the rotation of the disk and the disturbance they have caused are repressed by viscoelastic effect which is possessed by the polymer solutions. According to a Reiner-Rivlin model, the torque coefficients were arranged such that they might be dependent upon non-dimensional number (η_cω/η) in the laminar flows by approximate analysis, and upon (η_c/ρa²) in the turbulent flows by experimental data.

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In this report, the pressure surge resulting from a step change of an outlet flow is called the oil hammer and that of an inlet flow is called the transient response in a pipeline. The response waves of the pressure at an arbitrary position of the pipeline have been investigated by theoretical analyses and experiments under various line-conditions. The theoretical solutions involving the influence of a reflecting wave in the oil hammer and the transient response have been derived by using the equivalent viscous resistance. The equivalent viscous resistance has been derived by comparing between the viscous resistance of an unsteady flow and that of a steady one. It is shown that the theoretical solutions are in good agreement with the experimental results under various line-conditions.

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This report describes oil hammers and transient responses in the pipeline-systems with a volumetank. Theoretical solutions have been derived from two systems; one includes the volume-tank in the middle of the pipeline, the other at the end of the pipeline. The experiments in these systems have been performed under various line-conditions - the volumes of volume-tank, the diameters of pipeline and the coefficients of kinematic viscosity of oil in various combinations. The theoretical solutions are proved to be in good agreement with the experimental results under various line-conditions.

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A new accumulator is developed which is possible to absorb ripples by pump and cavitation in valve, ranging from several hundred to several thousand c/sec in the hydraulic system. (Acc: abreviation of Accumulator) The attenuation of Acc in the case of constant flow source and constant pressure source when the pipe is terminated with a throttling load, was computed and compared with experimental values. Observation of the bladders of hat and belows type used in this experiment, was made and by life test, the endurance limit of them was investigated. By improving the bladder's profile and smoothing stress distribution, the author affirmed that this Acc had good endurance limit under ripple pressure of about ±15 kg/cm².

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The local void fraction is one of the most essential parameters to clarify the precise structure of a two-phase flow. In the report, a new method is tried for the measurement of the local void fraction. The method is based on the principle that if there is a liquid metal at the top of the optical fibre glass probe, the signal light reflects and turns back the fibre glass. If not, the signal light scatters out. In the first report, the measurement is carried out in the case of a mercury-air two-phase flow in a vertical pipe. The present results show good agreement with those obtained by the method of pressure gradient.

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In order to make clear heat transfer to curved turbulent jets by adjacent boundaries, at first the mass transfer of a turbulent wall jet without deflection of the jet center line has been experimentally studied by the following programs using the technique of the sublimation of the sublimation of naphthalene. (a) Mass transfer at the developed region of a wall jet. (b) Mass transfer at the initial region of a wall jet. (c) Mass transfer from the discontinuous naphthalene surface to the developed wall jet. The experimental results are compared with an approximate analytical treatment, generalized to apply for the reattached wall jets to adjacent boundaries.

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Heat transfer to plane jet reattached on a flat plate, having an inclination for the plane nozzle, has been studied by the law of analogy from mass transfer, using the technique of sublimation of naphthalene. The flow development on an inclined flat plate depends on shapes of bubble induced due to separation and reattachment. The change of bubble shape occurs roughly at an inclined angle of 30°. Considering such flow field, empirical formulas were derived for the following items. (1) Maximum Sherwood number in reattachment region (2) Mean Sherwood number in separated bubble region (3) Local Sherwood number over the region of reattached wall jet (4) The effect of reattachment by the curved jet on distribution of the local Sherwood numbers.

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In this paper, the following problems about one-dimensional transient radial heat conduction in cylindrical co-ordinate system are discussed: (1) Difference equations of explicit type for boundary conditions of no flux across the surface, prescribed heat flux across the surface, linear heat transfer at the surface, non-linear heat transfer, contact with a well-stirred fluid or perfect condutor, and the surface of separation of two media of different conductivities are given. (2) The truncation errors by those difference equations are shown in series expansion. (3) The stability conditions of those difference equations are shown. (4) The effective domain covered with those difference equations is shown, by comparing them with difference equations for one-dimensional rectangular co-ordinate system which are given in our former report. (5) at_min/(Δr)²≥0.4∼2.6, t<min>/Δt≥6 are shown to be of sufficient conditions for the above difference equations, to obtain numerical solutions of accuracy within 2∼3% of the maximum temperature change.

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Experimental data of the condensate film thickness and the local heat transfer coefficient are presented for steam condensing in down flow inside a vertical tube. On the basis of the data obtained, the relations between the condensate film thickness, local heat transfer coefficient, film Reynolds number of condensate and shear stresses at tube wall and vapor-liquid interface are investigated and compared with the theoretical predictions for tubulent and laminar film condensation. A brass tube with an inside diameter of 24 mm was used as the test tube. The ranges of variables covered by this experiment are: 40∼90m/sec for the inlet velocity of steam, 0.2∼0.8 for the exit dryness fraction and 500∼2000 for the condensate film Reynolds number. A prediction is also presented for the thickness of laminar sublayer from the experimental data of local heat transfer coefficient by assuming that the condensate film consists of two layers, a laminar sublayer and a turbulent layer. The result indicates that the laminar sublayer thickness of condensate film is considerably different from that of single phase full tube flow.

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New thermodynamic equations of saturation temperature, specific volume, specific enthalpy, specific entropy and specific isobaric heat capacity both for saturated water and for saturated steam were formulated for the range of temperature between the triple point of water and the critical temperature. These equations are based on the International Skeleton Tables (1963) and degree well with the property values given in the 1968 JSME Steam Tables. They also have the following features suitable for computation with electronic computation with electronic computers; (i) simple expressions in a form with pressure and temperature chosen as independent variables and short computing time needed, (ii) small amount of memory cores required, (iii) sufficient accuracy assured in computed property values within the valid region of these equations. In the present paper these new equations, the computed results of thermodynamic properties and also the comparison with those of IST (1963), and of the 1963 IFC Formulation for Industrial Use are described.

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Investigation of the jets flowing from air entry holes of the liner of a gas turbine combustor was carried out using simplified models. Cold air was supplied through the air entry holes normally into the primary hot gas flows. The mass flows of the primary hot gas and issuing jets were measured and the behavior of the air jets was studied by the measurements of the temperature distribution of the gas mixture. The maximum penetration of the jets, the jet flow path, the mixing of the jets and the discharge coefficient of the holes were investigated. Some empirical expressions were obtained for the case of a simple air entry hole. The results showed that the penetration rate and the path of the jets flowing from paired holes parallel to the primary flow can be estimated from the modified empirical expressions obtained for the single air entry hole.

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A superconductive magnet is generally thought unsuitable for a magnetic bearing because this magnet must be placed in liquid helium. The authors propose a new rotor-supporting system suing the strong magnetic field of a superconductive magnet. The experimental prototype was manufactured and its performances were evaluated experimentally and theoretically. The prototype consists of a cryostat, superconductive magnets, a rotor, mechanical auxiliary bearing, and so on. This newly devised cryostat can transmit an attractive force to a rotor which is placed in a normal temperature atmosphere. The bearing can suspend a rotor with hundreds of kilograms in the thrust direction using a mechanical auxiliary bearing in the radial direction. Besides, complete levitation is made possible when the currents of magnets are controlled automatically.

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