Turbulent flow of inelastic non-Newtonian fluids in pipes

6 Turbulent flow of inelastic non-Newtonian fluids in pipes 

Turbulent flow of Newtonian fluids is described in terms of the Fanning friction factor, which is correlated against the Reynolds number with the relative roughness of the pipe wall as a parameter. The same approach is adopted for non-Newtonian flow but the generalized Reynolds number is used. 

For laminar flow of a non-Newtonian fluid, the wall shear stress can be expressed in terms of K and ri as 

On substituting for tw in equation 2.10, the Fanning friction factor for laminar non-Newtonian flow becomes 

This is of the same form as equation 2.14 for Newtonian flow and is one reason for using this form of generalized Reynolds number. Equation 3.35 

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