Frictional force measurement between a single plug and the pipe wall in dense phase pneumatic conveying

A new measurement technique to determine the frictional force between a plug and the pipe wall in dense phase pneumatic conveying was developed. Four strain gauges were installed on the outer surface of the pipe wall and strains were measured at different locations (top, back, bottom, and front) of the pipe wall, where the strain signals were obtained. The frictional forces were determined for different experimental conditions such as the superficial air velocity and the amount of material being transported. Polyester and polystyrenes with different size and shape, and polyolefin materials were tested in this study. It was found that the frictional force is related to the plug length as well as material properties such as size, shape of the polymer particles and contact area with the wall. In addition, it was found that the frictional force was the highest at the top or sides of the pipe and was smallest at the bottom of the pipe depending on the particle characteristics. The ratio of shear stress to the overall driving pressure for the plug decreased when the plug length is increased.

New method for measuring frictional force between particle and pipe wall in dense phase pneumatic conveying by using strain gauges attached on the outside of the pipe has been developed. The frictional force was related to the plug length and particle's material properties. The ratio of shear stress to the overall driving pressure for the plug decreased when the plug length is increased.Figure optionsDownload as PowerPoint slideHighlights
► Frictional force between plug and pipe wall was investigated.
► Frictional force has a linear to plug length.
► Frictional force is different for different material properties such as particle shape, size, and different material.
► Frictional force is different for the measuring location of the pipe.
► The ratio of shear stress to the overall driving pressure for the plug decreased when the plug length is increased.