Development of a Combined (Parallel & Parabolic) Rheomatic Device for Determination of Pressure Dependent Viscosity
Keywords:
Shear rate viscosity, Parabolic, Rotating speed, Newtonian fluid, PolymerAbstract
Hydrodynamic pressure technique is a relatively new and innovative technique for rheological studies of viscous Newtonian fluids. These principles extensively used for the last twenty years for drawing and coating of strips and wires. The Rheometric Device consists of a rotating inner cylinder (rod) in a fixed hollow outer cylinder. The complex geometry gap between the two cylinders filled with a viscous non-Newtonian fluid. When the rod rotates inside, while the hollow cylinder filled with a viscous fluid, shearing takes place and hydrodynamic pressure develops, the magnitude of which is dependent on the shape of the surfaces, the viscosity of the fluid as well as the shear rate, the speed with which the inner solid rod is rotating. The Rheometer has been developed to determine the Rheological properties of fluid at pressures of up to 100 bar and a shear rate range of 500 to 400 sec⁻¹. Theoretical model developed based on Newtonian characteristics, shear rate viscosity relationship was determined using the Rheometer (combined parallel and parabolic unit) at different pressures by comparing the calculated theoretical pressure distribution with the experimental results
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