This paper is concerned with the bed-load transportation from a trough in a horizontal wind tunnel. The air velocity employed was between 8 and 15m/s, and the bed-load consisted of glass beads. To study the effect of flow disturbance, a plate was installed at various angles and heights to the tunnel bottom upstream of the trough. In some experiments, the rate of air flow was altered periodically between two set values. The transient air flow influenced the bed-load transportation somewhat. The reverse flow caused by the plate has been found to have a significant effect on the bed-load transportation.

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The effects of crushing conditions on crushing rate, crushing energy and the particle size distribution of crushed products, in the crushing of GFRP by a rotary shearing crusher were investigated. The crushing rate increased with the decrease of clearance between the fixed and rotating blades and with the increase in the opening of the screen. The crushing energy and the particle size distribution depended on the opening of the screen, but their dependences on the clearance were found to be small. A crushing mechanism which could explain the influence of the clearance on the crushing rate was proposed.

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Solid additives are widely used to control the mechanical properties of powder materials in many industries. In this paper, the measurement of the tensile strength of a powder bed with a split-cell type tester was conducted to elucidate the effect of solid additives on the mechanical properties of powder materials.
Fused alumina powder, silica sand, limestone, lactose and potato starch were selected as the powder materials, and colloidal silica was used as a solid additive.
The relationship between the tensile strength and the porosity of powder bed containing the additive was proposed to characterize the effect of the additives on the mechanical properties of the powder materials.
Furthermore, experimental results reported by others were able to be explained by the above relationship.

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The transitional torque characteristics of the particles bed have been measured by using a rotary shear tester which is basically a Couette type rheometer. The torque measured on the rotor shaft under constant operating conditions shows the maximum value to be at the initial period. It then, decreases exponentially with changes in the packed state of the particles bed around the shearing surface over rotating time. The magnitude of the decay coefficient k of the torque indicates some of the dynamic physical properties of solid particles, such as flowability and surface condition. It was found that the conical rotor grooved on the shearing surface was suitable for more sensitive and accurate measurement of the torque change. A parameter k/N_R, where N_R is the rotor speed, was introduced and compared with the other parameters. It has been shown experimentally that this parameter was more sensitive in detecting slight changing in physical properties during and/or after mixing and coating operations. The coating processes of two different types of mixer and the coated state of the binary mixture have been evaluated based on this parameter.

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