The separation of an axial displacement and a rotational angle at the center of an element makes it possible to derived a new finite element method (FEM) from the ordinary one for small strain. The new FEM is non-incrementally applicable to the analysis of geometrically complicated structures consisting of deformable and undeformable shapes such as gears under concentrated twisting moment. the two-dimensional static behaviors of a cantilever beam are investigated to verify practical applicability of the new FEM. The lumped mass matrix (LM) and the consistent mass matrix (CM) are derived, to calculate the natural frequencies of the beam by use of their matrices. The results calculated by the new FEM agree well with those of the beam theories for the static and dynamic behaviors.

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One predicting method is presented for determining the incipient condition of gaseous cavitation by analogy with a local choked flow condition of a homogeneous bubble mixture. Cavitation criterion is defined as a condition in which the flow velocity reaches the local isothermal sonic velocity. As the result of an experimental confirmation which was performed by measuring the choking characteristics of pressure wave propagation at the throat, a reasonable agreement is obtained between the desinent condition and an estimated chocked flow one. It is also shown that the predicting method is useful to estimate qualitatively some gaseous cavitation phenomena presented hitherto, and cavitation inception in a sodium has a similar tendency to that in cold water.

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With use of radial flow pumps having different numbers of impeller blades, the performance of the pumps under air admitting conditions was examined in various capacities and cavitating conditions. In a pump with normal blade number, the flow pattern in the impeller was not altered by admission of small quantities of air, and the impeller worked normally in both cavitating and non-cavitating conditions. In this case, reduction of the pump performance is caused mainly by an additional hydraulic resistance due to the admitted air. In a pump with a too small blade number, the air admitted may bring about an increase of the pump head both in the non-cavitating and incipient cavitating conditions, which results from an improvement of flow pattern in the impeller due to the occurrence of cavitation.

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In the past, the hydraulic losses and the flow patterns in pipe bends when a fully developed flow enters the bend were studied. But, practically, most of the flows are not uniform in the axial velocity component and accompanied with a swirling components, which causes different hydraulic losses and flow patterns in the bends. Such problems remain almost unsolved at present. In the present paper, the effects of curvature and surface roughness on the hydraulic losses and flow patterns of a swirling flow in u-bends are studied.

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A discrete-vortex model is developed for a separated flow past a nearly normal plate immersed in a uniform flow. A reduction in the strength of vortices is introduced as a function of their age to simulate the cancellation of vorticity in near wake. The mean and fluctuating velocities in the near wake, the drag and the convection velocity of rolled-up vortices showed fairly good agreement with experiment. An unifavourable aspect of the reduction in the vortex strength is to yield a higher Strouhal number of vortex shedding than experiment.

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In this paper, the influence of weak radiative heat transfer on measured thermal conductivity by the transient line source technique is discussed. Fundamental equations and non-dimensional parameters (emissivity, ε; Fourier modulus, t*=at/(r₁)² ; optical thickness, R=Kr₁ ; non-dimensional radius, r*=r/r₁), which determine the apparent thermal conductivity, λapp, are shown, and the relations between these parameters and radiative heat flux, temperature distribution and λapp are discussed using the results of numerical calculations. The optical condition, R=0.010.07, where the influence of radiation appears maximum for t*<600, is pointed out. This optical condition corresponds to the measurements of Ccl₄ or toluene for the usual line radius, r₁=12.5μ. As λapp increases rapidly in the range of small t* (t*<200), the extrapolation, t*→0, using λapp - t* curves (t*<200), doesn't give the real thermal conductivity, λ. A method to modify λ_app is proposed.

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Wall friction and local heat transfer in an oscillating laminar boundary layer over a flat plate with an unheated starting length are theoretically analyzed. In the analysis, the power series solutions are derived for velocity and temperature distributions in three frequency regions, that is, low frequency (ω*<1), intermediate frequency (1<ω*<1/K), response of a hot film sensor is clarified theoretically. Especially it is shown that the amplitude of heat transfer oscillation with an unheated starting length increase with frequency at low and intermediate regions, and the phase angle is in advance of free stream oscillation at these frequency regions.

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A new theoretical model, based on the radial temperature distribution of water that has been measured at the subcooled coiling region, is presented for the prediction of an actual quality in the subcooled flow boiling at elevated pressure. The predicted actual quality is converted into the void fraction using Smith's void correlation. Applying a part of the theoretical results, a simple calculation method of void fraction is also proposed. These prediction methods are compared with the experimental results which cover the following conditions ; pressure : 1.0140.6 ata, heat flux : 1.6×10⁴326×10⁴ kcal/m²h, mass velocity : 130.55097 kg/m²s. Agreement between void fraction calculations and experiments is good.

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In the previous work we reported an experimental investigation on the flow pattern in an agitated thin film horizontal evaporator without thermal effects. In this work, we theoretically researched an axial flow of the working liquid of low viscosity in the horizontal apparatus neglecting thermal effects and compared the theoretical results with experimental ones.

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Condensation cycles power generation employing carbon dioxide as a working medium are suitable for large capacity steam and nuclear power stations. In order to make clear the static and the dynamic characteristics of the power plant, a test facility composed of a pump, a regenerator, a heater, a turbine, a blower, and a condenser was constructed and operated. Following the 1st report presenting the static characteristics, the dynamic characteristics of the entire system are presented and the physical meaning of the response is discussed in this report, referring to the theoretical analysis based on a simple lumped-parameter model. As a result, fundamental information useful in planning the control systems of actual CO₂ power plants is obtained.

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A theoretical analysis of the dynamic characteristics of power plants using carbon dioxide as a working medium is conducted and comparisons with the experimental results reported in the 2nd report are made. Mass, energy, and momentum conservation equations are linearized for each element of the CO₂ power plant, that is, a pump, a heater, a turbine, a blower, piping system, and control valves with a lumped parameter model. Then, respective transfer functions are obtained and connected as a total system. A simulation of the dynamic characteristics for the experimental apparatus of a small-scale supercritical pressure carbon dioxide power plant was conducted with a digital computer. The results of the theoretical analysis agreed well with the experimental results of the theoretical analysis agreed well with the experimental results. This analytical method would be applicable for the estimation of the dynamic behavior of large scale CO₂ plants.

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In order to utilize the low temperature exergy of the liquid hydrogen, the characteristic of a gas turbine cycle employing a precooler and an auxiliary hydrogen turbine is discussed. The thermal efficiency and specific output of this cycle are superior to those of the simple cycle gas turbine which has the same components' efficiencies. The low temperature exergy is converted to work by decreasing the compressor input and hydrogen turbine output addeed. The merit of improvements in specific output of this cycle is about 20 percent of that of the simple cycle. The pressure loss coefficient of the precooler is very critical to the merit of improvements of the thermal efficiency. The critical value is about 5 percent. The thermal efficiency and the specific output are increased with an increasing ambient temperature, thus the performance degradation of the simple cycle gas turbine at high ambient temperature can be improved by introducing a precooling system.

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The gyroscopic action of a rotor tends to split up the unstable regions which results mainly from the asymmetry of shaft stiffness Δ into several parts by the inequality of bearing stiffness ε. The analysis of this problem is carried out on the assumption that the coefficient of gyroscopic term i_p is as small as ε and Δ, or i_p is larger than both ε and Δ. The position, width and number of unstable regions are analytically determined. As the value i_p increases, the higher side of the split unstable regions becomes larger, but the lower side becomes smaller. The analytical results obtained with the approximation that i_p is large in comparison with both ε and Δ show a good coincidence with results obtained by an analog computer.

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Systematic displacement analyses of plane multilink mechanisms with clearances and tolerances have been carried out using two kinds of transformation functions. One of the functions may be used to evaluate the influences of bearing clearances upon the output displacements, and the other may be used to analyze the distribution of output errors due to distributions of clearances and tolerances. In these analyses, neither derivations of displacement equations nor initial conditions are necessary for numerical calculations.

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It is hard to design high quality reduction gears composed of rollers as gear teeth, because the reduced rotation has irregularities inevitably. In this report, the optimum design of roller tooth gears for power transmission was investigated. According to this design, the K-H-V type planetary reduction gears of the reduction ratio of 1/15 were produced on trial. The following performances were obtained. (1) Irregularities of reduced rotation were less than 0.028 degrees. (2) Efficiency of power transmission was 80-90%. According to these results, it is possible to put this reduction gears to practical use.

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A method is shown to estimate the degree of vibrational excitation of involute helical gears due to transverse and longitudinal tooth form errors and periodical change of tooth stiffness with progress of meshing. Some charts and a table are shown to give the results of this analysis for the combinations of four gear pairs of different dimensions and four different kinds of tooth form errors. The analysis shows, that the convex tooth form error is the most harmless among different kinds of tooth form error shapes such as concave, waving tooth form error, pressure angle error and so on. The effect of convex tooth form correction for helical gears is recognized the same as the case for spur gears. With increase of total contact ratio or of helix angle, the magnitude of vibrational excitation becomes strongly weakened.

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In this paper, as the basic study to clarify the scoring resistance of lubricating oil in Two Cylinder test, temperature rise of cylinder was analyzed by both theoretical methods and the Method of Weighted Residuals, and the effects of various factors on the temperature rise of cylinder were examined by numerical calculations. Unlike the temperature rise of steel ball in Four Ball test, temperature rise of cylinder cannot be divided into two kinds of components with different properties without regard to rotating speed. However, an important item i the evaluation of thermal resistance of lubricating film is the outer surface temperature of cylinder. As the result of examination, it is made clear that in heat supply region and in its neighborhood the temperature rise on the outer surface of cylinder can be divided into two components. One is flash temperature and the other bulk temperature rise. The former is affected by the size of heat supply region, rotating speed, and heat source distribution, and in dimensionless rotating speed ω^^->500< by contact width in axial direction. The latter is affected by the coefficient of heat transfer, rotating speed, and contact width in axial direction.

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This paper deals with a problem of facilities location. Fundamental suggestion is making an individual location algorithm for combination of " Presupposition" and "Objective function" in each location problem. The presupposition of this paper is "that facilities locate straight", and the objective function is "to minimize Backward Distance Intensity". This new facilities location algorithm to select "minimum Backward Distance × Intensity location" is developed by using a property on Cut Set matrix that is a part of graph theory. The feature of this algorithm is ability to select the optimal solution by only using easy matrices manipulation. Trial of this algorithm in regard to an actual 6 facilities location is described here in.

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