The flow behavior of particles was studied with particular attention to the effect of the inclination of a storage vessel and/or the turn table of a table feeder. Two types of storage vessel, rectangular and cylindrical were used. The vessels have no hopper part (no contraction), and the scraper of the feeder is not utilized.
It was found that the particle-flow was intensely distorted when the lower level of the vessel was not parallel to the table surface. The slight inclination (as small as two degrees) between the vessel and the table causes this intense distortion of particle-flow. The distortion becomes more intense as the inclination increases, and the powder flow rate from the feeder increases exponentially with the angle of inclination.
It was also found that a new theoretical equation for the cylindrical vessel was successfully adapted for the estimation of the effect of the skirt-clearance on the powder flow rate. The upper and lower limits of the skirt-clearance were also discussed.

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A transient state simulation of a moving granular-bed type heat exchanger, in which heat is transferred from the hot gas through granular materials and heat pipes to the cold gas, has been performed. A numerical simulation model was developed by dividing each part of the heat exchanger, and the changes in temperature of each part were calculated using the Euler method.
The changes in temperature of some parts of the heat exchanger under conditions which demonstrated periodic changes in the inlet temperature or flow rate of heating gas were compared with the data obtained from the experiment, which was conducted under the same conditions. The calculation results coincided with the results of the experiment.
The main feature of the moving granular-bed type heat exchanger is its capacity to recover waste heat stably. This was clarified from the simulation calculation of the pilot plant with the heating gas condition equivalent to that of the converter outlet gas.

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The effects of the dimension of a movable plate, the twist condition and the roughness of the surfaces of the movable plate and fixed plate in contact with the powder on the powder yield locus (P. Y. L.) measured by a direct shear tester with parallel plates are examined.
From the results, the proper experimental conditions are as follows:
1) The dimension of the movable plate have an effect on P. Y. L., and so the suitable dimension for measurement are determined.
2) A normal stress of about 0.28kPa is suitable for the twist.
3) The surfaces of the movable plate and fixed plate have an irregular roughness like sand paper which is better than a surface which has a regular roughness, such as notching.
Furthermore, as a result of measuring several powders at the above proper conditions, . it is recognized that f_c/γg is more suitable to evaluate the flowability of powders than σp/f_c.

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The coordination number was first reported by Ouchiyama and Tanaka for particulate materials having a range of sizes. Based on this statistical theory the present paper deals with the problem of predicting whether a given binary liquid mixture might form an azeotrope or not.
First, the total sum of intermolecular potentials should be calculated from the numbers of A and B molecules adjacent to a molecule of A component and B component.
Assuming the ratio of the total sum to the boiling temperature of the mixture to be constant, a maximum value of the total potentials can be obtained in relationship to the mole fraction, by varying the degree of interaction between A molecule and B molecule until the mole fraction to give the maximum coincides with the mole fration of the exist ing azeotropic points of some 40 kinds. The degree of interaction thus obtained between the different kind of molecules can be correlated with the molecular parameters with respect to size, shape and potential.
As the results, the azeotrope prediction can be made to 88% probability with 137 mixtures available, by using only the molecular parameters of each component. If a specific binary mixture is predicted to be an azeotropic one, then the azeotropic point (temperature and concentration) can also be evaluated quite satisfactorily. The boiling curves for some selected binary systems are illustrated from the present theory. Agreement between the theory and experimental data is reasonably good.

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