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multivariate production systems optimization - Stanford University

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A paper by Hazim and Nimat (1989) proposed that the performance of the Aziz et<br />

al. (1972) correlation could be improved by using other flow-pattern maps instead of the<br />

map proposed by Aziz et al. (1972). For their specific data set, best performance was<br />

attained when the Aziz et al. (1972) correlation was used in conjunction with the Duns and<br />

Ros (1963) flow-pattern map.<br />

Ny<br />

10.<br />

1.0<br />

0.1<br />

.01<br />

Bubble<br />

B12<br />

Slug<br />

29<br />

B23<br />

Transition<br />

B34<br />

Annular-Mist<br />

0.1 1.0 10. 100. 1000.<br />

Figure 3.2: Flow-Pattern Map Proposed by Aziz, Govier, and Fogarasi (1972).<br />

3.4.1 Bubble Flow Regime<br />

To obtain the pressure gradient due to fluid density in the bubble flow regime, Aziz et al.<br />

(1972) proposed to define the liquid holdup as<br />

where the absolute bubble rise velocity is<br />

and the bubble rise velocity is<br />

Nx<br />

HL = 1 - VSG<br />

VBF<br />

VBF = 1.2 VM + VBS<br />

VBS = 1.41 σL g ρL - ρG<br />

ρ L 2<br />

1 4<br />

(3.51)<br />

(3.52)<br />

(3.53)

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