Mud rheology - Herschel and Buckley law
Input(s)
\(\tau_{\mathrm{y}}\): Yield Stress \(\left(\mathrm{lb} / 100 \mathrm{ft}^{2}\right)\)
\(\mathrm{K}\): Consistency Index \(\left(\mathrm{lb} / 100 \mathrm{ft}^{2}\right)\)
\(\gamma\): Shear Rate \((1 / \mathrm{s})\)
n: Power Law Index, Slope of Plot Between Log Shear Stress and Log Shear Rate (dimensionless)
Output(s)
\(\tau\): Shear Stress \(\left(\mathrm{lb} / 100 \mathrm{ft}^{2}\right)\)
Formula(s)
\[
\tau=\tau_{\mathrm{y}}+\mathrm{K} *\left(\gamma^{\mathrm{n}}\right)
\]
Reference(s)
Samuel. E Robello. 501 Solved Problems and Calculations for Drilling Operations. Sigma Quadrant. 2015. Houston, Texas, Page: 185.