The measurement of fluid response under deformation conditions closer to the actual flow process is called mixer viscometry. A helical ribbon impeller fitted to a rheometer was used to measure torque-impeller rotational speed of Newtonian, shear thinning and shear thickening fluids, which simulate many real fluid foods. Raw experimental variables were transformed to process viscosity using laminar-mixing principles. At a given impeller rotational speed, increasing the level of pseudoplasticity, power consumption decreases and thus the process viscosity. Increasing the solid-particle concentration, shear thickening increases. For two-phase fluids, the estimation of the viscous properties with classical geometries produces wrong results. For these systems, a helical ribbon based viscometry gives useful data for design, scale-up and comparison purposes.
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