Power-Law Generalization of Newton’s Formula for Shear Stress in a Liquid in the Form of a Tensor Rheological Relation

Abstract

A generalization of Newton’s formula for shear stress in a fluid is carried out by giving it a power-law form and the corresponding rheological relation is written in tensor form. Depending on the exponent in this rheological ratio, one can come to a description of either a laminar or turbulent flow regime. In the latter case, there is a system of differential equations with the no-slip boundary condition. The proposed set of equations for turbulent fluid motion can be useful, at least, for obtaining preliminary, estimated characteristics of turbulent flow before starting numerical modeling using modern differential turbulence models. For some values of the exponent, this system can be used to describe the behavior of power-law fluids as well as fluids with small additives of polymers in the manifestation of the Toms effect.