Pneumatic Escalator, which was devised for conveying particles upwards as well as in horizontal direction, consists of a series of oblique cells bounded by the inclined prallel plates.
Particles are fluidized in each cell and conveyed consecutively to the next cell.
Heat transfer characteristics of the equipment is examined and reported in this paper.
It is found that the volumetric heat transfer coefficient of the present equipment is as large as that of a fluidized dryer and is correlated only with the apparent velocity of the paticles passing through the equipment. An experimental equation for the relationship is proposed. Thus, the Pneumatic Escalator can effectively be utilized for the thermal operation as well as the transportation of particles.

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Side-wall pressure distributions and bottom pressures of annular powder beds in a double-cylinder rotary shear tester have been measured under both the dynamic (the inner cylinder is rotating) and static (the inner cylinder is stationary) conditions for a variety of powders. The effects of the powder bed height, the diameters of annular bed, and the rotational speed of the inner cylinder on the side-wall pressure distribution along the bed height and the bottom pressure have been examined. Janssen's equation applied to only the satatic cases with small bed heights and large outer cylinder diameters and did not hold in the dynamic cases where anomalously high pressures obtained in comparison with the static pressures. The ratio of the static sideall to bottom pressures (the static pressure coefficient) was always less than unity and the bed was in an active state in the vertical direction. The dynamic pressure coefficient, however, increased to greater than unity as the bed height increased, and the bed under the dynamic condition changed gradually from active to passive states in the vertical direction.
These findings should be considered if the internal friction factor of a powder is to be measured properly by a double-cylinder rotary shear tester.

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A double-cylinder rotary shear tester has been developed which can measure the shearing torque exerted on the inner rotating cylinder and the side wall pressure distribution on the outer stationary cylinder simultaneously. Various powders were tested by changing the powder bed height, the outer cylinder radius and the rotational speed of the inner cylinder.
The torque was shown to be proportional to the square of the powder bed height. The stress normal to the shearing plane at the inner cylinder was estimated from the relation of the side wall pressure distribution to the outer cylinder radius and the internal friction factor was evaluated without introducing Rankine's passive powder pressure coefficient.
The internal friction factors thus obtained for some of the powders tested were in good agreement with those measured by a direct shear tester.

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