Kinetic friction
Input(s)
\(\mu_{\mathrm{s}}\): Static Viscosity \((\mathrm{cP})\)
a: Constant of Friction in X Direction (dimensionless)
\(\mathrm{g}\): Acceleration Due to Gravity \(\left(\mathrm{ft} / \mathrm{s}^{2}\right)\)
Output(s)
\(\varphi\): Angle of Friction (rad)
\(\mu_{\mathrm{k}}\): Kinetic Viscosity (cP)
Formula(s)
\[
\begin{gathered}
\varphi=\tan \left(\mu_{\mathrm{s}}\right) \\
\mu_{\mathrm{k}}=\mu_{\mathrm{s}}-\left(\frac{\mathrm{a}}{\mathrm{g} * \sin (\varphi)}\right)
\end{gathered}
\]
Reference(s)
Samuel. E Robello. 501 Solved Problems and Calculations for Drilling Operations. Sigma Quadrant. 2015. Houston, Texas, Page: 375.