[in Japanese]

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[in Japanese]

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An experimental study was performed for the analyses of the behavior of liquid jet and the mechanism of drop formation from the jet, and for the prediction of the mean diameter of drops, when organic liquid is injected through a nozzle into turbulent pipe flow of water.
The mechanism of drop formation is characterized as a function of the velocity at the nozzle top relative to the continuous phase velocity as follows:(a) drop formation controlled by the turbulent pressure of continuous phase flow acting on the jet, (b) drop formation by the amplification of the unstable waves appeared on the jet, and (c) drop formation of the spray type. For each rigion classified above the mean diameters of drops are correlated with velocities of both liquids, liquid properties, and nozzle diameter.

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A flow of rarefied gas between two parallel plates was analyzed. In analysis, it is assumed that the mechanism of momentum transport is specified by the Newton's law even in the transition flow regime. In this paper, a new model is offered, in which a transport distance of physical quantities is introduced into a calculation of viscosity. The transport distance includes a modified coefficient ε which is related to an effect of molecular-wall collision upon a mechanism of momentum transport of gas molecules.
Although it may be predicted that a is not concerned with types of collision but also with accomodation coefficient, an explicit discussion of physical meaning of modified coefficient has not been given.
But it was found out by experiment that the value of a is constant in all flow regime, and so that a model in this paper is very useful in a technical treatment.
The equation of flow calculated using present theory for some typical values of c is in fair agreement with the solution of the Boltzmann-equation which is analyzed using the BGK-model and the hard sphere model.

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The heat input rates to a spherical probe immersed in an atmospheric argon plasma of which temperature is 13, 200°K at maximum were measured by means of the copper-constantan thermocouple, applying the potentials ranging from -30 V to 5 V. The conclusions were obtained that the heat input rates to the electrically floating probe coincide fairly well with that calculated by the Back's theory, and that, at the highly negative potential, 65% of the joule heating generated around the probe is added to the probe.

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Factors which affect on particle deposition to horizontal pipe wall from turbulent stream are friction velocity, particle settling velocity, circumferential angle and pipe diameter. Effects of these factors were studied experimentally and theoretically, and experimental results were in fairly good agreement with calculated ones.The gravity effects on particle deposition may be considerably important, even if flow is in turbulent condition.
Friedlander's formula for the aerosol deposition on the vertical pipe wall was modified and new expression was obtained which is applicable to both the horizontal and the vertical pipe.
Consequently, optimum condition which minimizes the horizontal sampling losses has been determined.

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An experimental study of the size effect of single particle crushing under slow rate of compression was carried out by using spheres made of 6 kind of glassy materials and minerals.The sphere diameters ranged from 3.0 to 0.0030 cm.A summary of experimental results was as follows, 1) compressive strength of spheres of glassy materials was continuously increased with the decrease of their volumes, 2) compressive strength of particles of minerals was discontinuously increased with the decrease of their volumes, 3) this discontinuity may be due to the status of pre-existent flaws of specimens.

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Dynamic response of a multiplate gas-liquid reactor is investigated by means of a transfer function analysis taking into account of both fluid flow lags and the dependence of overall reaction rate upon various process variables, such as flow rates and reactant concentrations.The transient responses simulated on analogue computor are said to agree well with those obtained experimentally with a laboratory equipment if the effects of the nonlinear behavior on the experimenta results are taken into considerations.Performance of the feedforward control system previously proposed is also investigated with the reactor on the basis of the mathematical model proposed.

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The reduction of porous tablets, which were prepared from the ground particles by burning, in hydrogen gas was performed in a flow system at temperatures from 450 to 600°C.Fractional conversion of reduction was measured by the weighing method.
It was found that the induction period appeared at the initial stage of the reaction, and the reaction zones forming hemisphere spreaded inward the particles.
The reasons of appearance of these phenomena were explained by the effect of burning on the reactivity of solid surface.

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