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All About Granular Material & Flow Measurement Device Granular material is a conglomeration of discrete macroscopic particles, that exhibit unique properties when subjected to forces. They behave like solids, liquids and gases under different conditions, but yet exhibit unique characteristics even in these states, not typical of the three states of matter. Loss of energy due to friction is the main characteristic of granular material. Brigadier Ralph Alger Bagnold who was also a physicist, was the pioneer in the study of granular material. Granular Material is used commercially and has applications in the pharmaceutical industry as well as in agriculture and energy production. It is the second most manipulated natural entity after water. Powder is also a granular material, with very small size particles making them more cohesive and likely to be suspended in a gaseous medium. What are the principles to measure the flow of a granular material such as powder? The study of granular flows is called rheology. Rheology is relevant in many geo physical and industrial contexts like sediment flow, slurry pipelines, mining and milling operations etc. When, particle to particle interactions dominate the flow of the material as in granular material, the flow patterns are different from normal fluids. The boundary and interstitial fluid if any also have a unique impact on the flow of granular material as well as the elastic nature of the particles themselves. Flow is a measurement of velocity over a known area. Since the granular material has a combination of forces within, that are subject to change with changes in the environment, many manufacturers of flow instruments measure the flow properties of the powders and other granular material before attempting to measure the flow. This information helps scientists to predict how the powder will behave in their processes. Powder flowability is one such property which displays problems at times, hampering the entire process. It is defined as the ease with which a powder flows under a specified set of conditions such as the pressure on it, the humidity of the environs, and the equipment through which it flows. Powder flowability tester and powder flow testers are flow instruments to understand the nature of any given powder under flow conditions. These instruments analyze the powder in the flowing state and about to flow state. There are a few flowability testers in use, which fall under two types of analyses, dynamic (flowing) and static (analysis of powder behavior under pressure and shear cell analysis of flow properties of powders under pressure). The dynamic testers are called Revolution Powder Analysers, while the Evolution powder tester measures the effect of pressure on the powder flow and the Volution Powder flow test looks into the shearing activity (both static). These double up as flow measurement devices as they actually measure the flow of the powders under the given conditions. Powder handling equipment is used so that the powder doesn’t get exposed to pollution and contaminants, nor does it contribute to the same. They are used keeping safety concerns of the personnel in mind. Pneumatic conveyance is a modern method over mechanical and manual transport.


The study of powder as a special condition of granular flows has a lot of applications and has given rise to many manufacturers of precision machines catering to this industry. Information Shared By – http://www.granutools.com/.


All About Granular Material & Flow Measurement Device