multivariate production systems optimization - Stanford University
multivariate production systems optimization - Stanford University
multivariate production systems optimization - Stanford University
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NV ≤ 18 25<br />
18 < NV < 250 69 NV -0.35<br />
250 ≤ NV<br />
10<br />
Having obtained the liquid holdup, the hydrostatic head component of the total pressure<br />
gradient is<br />
31<br />
dP g<br />
=<br />
dZ HH gC ρL HL + ρG HG = g<br />
gC ρS<br />
The friction component in slug flow is evaluated as<br />
dP =<br />
dZ F<br />
fM<br />
2<br />
ρL HL VM 2 gC D<br />
where the Moody friction is obtained using a Reynold’s number of<br />
Re = ρL VM D<br />
μL<br />
(3.62)<br />
(3.63)<br />
(3.64)<br />
(3.65)<br />
(3.66)<br />
(3.67)<br />
As in the bubble flow regime, the acceleration component was considered to be negligible<br />
in the slug flow regime. Therefore, the total pressure gradient for the slug flow regime is<br />
given by<br />
3.4.3 Transition Flow Regime<br />
dP =<br />
dZ SLUG<br />
dP +<br />
dZ HH<br />
dP<br />
dZ F<br />
(3.68)<br />
The transition flow region is, as the name indicates, a region of transition between the slug<br />
flow region and the annular-mist flow region. When flow occurs within the transition<br />
region, the pressure gradient is obtained by performing a linear interpolation between the<br />
slug and annular-mist regions, as suggested by Duns and Ros (1963). The interpolation is<br />
performed as follows:<br />
dP =<br />
dZ TRANS<br />
N3 - NX<br />
N3 - N2<br />
dP +<br />
dZ SLUG<br />
NX - N2<br />
N3 - N2<br />
dP<br />
dZ MIST<br />
(3.69)