Relates pressure drop \Delta p = p_{in} - p_{out} on the choke with the flowrate through the choke q arising from fluid friction with choke elements (ISO5167):
| (1) | \Delta p = p_{in} - p_{out} = \frac{ \rho \cdot (1- \beta^4)}{0.125 \, \pi^2 \, d^4 \, C_d^2 \, \epsilon^2} \cdot q^2 |
where
\rho | fluid density |
d | orifice diameter |
D | pipe diameter |
\beta = \frac{d}{D} | orifice narrowing ratio |
C_d | |
\epsilon | expansion factor |
| (2) | p_{wf, k} = p_{out} + \rho \, g \, z_k |
| (3) | q = \sum_k \frac{B_w(p_{e, k})}{B_w(p_{out})} \cdot J_k \cdot \left[ p_{out} + \rho \, g \, z_k - p_{e, k} \right] |
which is equivalent to (1).