Formula 4.98
Velocity of fluid in annulus
Input(s)
$Q$: Flow rate $(\mathrm{gpm})$
$D_{o}$: Open Hole Diameter (in.)
$D_{p}$: Outside Diameter of Pipe (in.)
Output(s)
$v_{a}$: Velocity of Fluid in Annulus (ft/s)
Formula(s)
$$ v_{a}=\frac{Q}{2.448 *\left(D_{o}^{2}-D_{p}^{2}\right)} $$
Reference(s)
Samuel. E Robello. 501 Solved Problems and Calculations for Drilling Operations. Sigma Quadrant. 2015. Houston, Texas, Page: 321.