A thorough investigation of the sawdust's angle of repose subjected to a spectrum of stimulating vibration frequencies, using a specially developed testing device.

The transportation and storage of powdered bulk materials is an important part of the manufacturing process of many products and requires equally important productive resources such as time, space and capital. Accurate estimation of these materials' mechanical properties, especially those related to the above processes, such as the angle of repose provides information necessary for the design of optimized mechanical systems that minimize production costs. In the context of the present study, a mechanical device has been developed at the Machine Design Laboratory of the School of Pedagogical & Technological Education (ASPETE) for the determination of the angle of repose of bulk materials, a dimension necessary for many calculations related to machinery, such as maximum capacity e.g. of conveyor bolts, straps and lifts. This device allows studying this property very accurately under various vibration conditions, thus giving more realistic and much more useful results. Measurements were conducted on dry and wet sawdust, a raw material of many important product, and angle-of-repose diagrams were generated with respect to stimulating vibration frequency.