Logarithmic Correlations For Turbulent Pipe Flow Of Power Law Fluids

TL;DR

This paper derives logarithmic correlations for turbulent friction factors in power law fluids using phase-locked parameters and modern turbulence understanding, achieving high accuracy with a small standard error.

Contribution

It introduces new logarithmic correlations for turbulent friction factors in power law fluids based on phase-locked parameters and turbulence structures.

Findings

Correlations predicted 264 data points with 1.3% standard error.

Two different analysis techniques yielded different coefficients.

Modern turbulence understanding aids in deriving engineering head loss correlations.

Abstract

This paper uses the estimates of phase-locked parameters at the onset of bursting presented in a companion paper to derive logarithmic correlations for turbulent friction factor losses in time-independent power law fluids. Two different techniques for analysis were used. They gave logarithmic correlations with different coefficients. But both correlations predicted 264 data points of friction factors published in the literature with a standard error of 1.3%. The derivations show how modern understanding of coherent structures embedded in turbulent flow fields can be used to derive engineering correlations for head losses. Key words: Friction factor, turbulent, logarithmic correlations, power law, non-Newtonian