Fow in rotational viscometers 六亡 viscosity at a given shear rate or shear stress. +音 公岳 rate is approximately the same everywhere Parallel Plates Cone Plate (variable gap) (fixed gap) CONE AND PLATE Shear rate Shear stress 3T 0=2R Newtonian fluids 3Ta T=Torque n=%-2成n 77 Parallel Plates (variable gap) Cone & Plate (fixed gap) CONE AND PLATE Ω R α Shear stress T Torque R T = = 3 2 3 π σ Shear rate γ . = Ω α Ω = = 3 2 3 Newtonian fluids R T π α γ η σ &