Non-Newtonian Fluid Books

Non-Newtonian Fluid Books

Source: FluidFlow

Non-Newtonian fluids are encountered in a wide and varied range of industrial processes including food, mining and minerals, pharmaceuticals, pulp and paper processing and other products in the form of pastes, slurries, concentrated solid suspensions or emulsions. Examples include coal slurries, mud, sludge, paint, ketchup, mayonnaise, blood, shaving cream, toothpaste, dilute solutions etc. These fluids regularly exhibit non-Newtonian viscous properties and it is important for the designer to be familiar with the flow behaviour of such fluids, how to characterise the fluid physical properties of these fluids and how to use these properties to predict flow behaviour in process piping systems.

Newtonian fluids exhibit a linear relationship between shear rate and shear stress. The slope μ (viscosity) is constant and therefore, the viscosity of a Newtonian fluids is independent of shear rate. Non-Newtonian fluids on the other hand typically exhibit either shear thinning or shear thickening behaviour and in some cases, exhibit a yield stress, i.e. a stress level which must be overcome before the fluid begins to flow. There are a number of common rheology models or methods often used to characterise Non-Newtonian fluids. These include the Herschel-Bulkley, Power Law, Casson and Bingham Plastic models.