Hydraulics analysis
Input(s)
\(N_{1}\): Jet Size for nozzle 1 (in.)
\(N_{2}\): Jet Size for nozzle 2 (in.)
\(N_{3}\): Jet Sizefor nozzle 3 (in.)
Q: Circulation Rate (gpm)
Dh: Diameter of Hole (in.)
Dp: Dia of Drill Pipe (in.)
MW: Mud Weight (psi)
B: Bit Size (in.)
\(P_{s}\): Surface pressure \((\mathrm{psi})\)
Output(s)
AV: Annular Velocity (ft/min)
\(\mathrm{Pb}\): Bit Nozzle Pressure Loss (psi)
HHP: Hydraulic Horsepower at bit (hp)
HHPba: Power per unit area in sq inc (hp/in. \({ }^{2}\) )
\(P_{p s i b}\): Percentage pressure loss at bit (percent)
\(V_{n}\): Jet Velocity \((\mathrm{ft} / \mathrm{s})\)
IFa: Impact force per unit area in sq inc (lb/in. \(\left.{ }^{2}\right)\)
Formula(s)
\[
\begin{gathered}
A V=24.5 * \frac{Q}{D h^{2}-D p^{2}} \\
P b=156.5 * Q^{2} * \frac{M W}{\left(N_{1}^{2}+N_{2}^{2}+N_{3}^{2}\right)^{2}} \\
H H P=P_{s} * \frac{Q}{1714} \\
H H P b a=Q * P b * \frac{1.27}{1714 * B^{2}} \\
P_{p s i b}=P b * \frac{100}{P_{s}} \\
V_{n}=417.2 * \frac{Q}{N_{1}^{2}+N_{2}^{2}+N_{3}^{2}} \\
I F a=M W * V_{n} * Q * \frac{1.27}{1930 * B^{2}}
\end{gathered}
\]
Reference(s)
Formulas and Calculations for Drilling, Production and Workover, Second Edition, Lapeyrouse, Page: 170.