Drag Coefficient and Settling Velocity of Particles in Non-Newtonian Suspensions

Drag forces on bodies in non-Newtonian fluids which are to be described by using the Reynolds number should only contain forces which are associated with the fluid velocity or particle velocity. Forces due to the yield stress τ₀ must be considered separately. According to its physical composition, the Reynolds number must be calculated by means of the fully representative shear stress including the yield stress τ₀. Then the drag coefficient c_D as a function of the Reynolds number can be traced back to that of Newtonian fluids.