Stratified flow, pressure drop model

A separated flow model for stratified flow was presented by Taitel and Dukler (1976a). They indicated analytically that the liquid holdup, R, and the dimensionless pressure drop, 4>G, can be calculated as unique f unctions of the Lockhart-Martinelli parameter, X (Lockhart and Martinelli, 1949). Considering equilibrium stratified flow (Fig. 3.37), the momentum balance equations for each phase are... 

The assumed dependence of pressure drop on X was first explained by Johannessen (1972) in evolving a theoretical model for stratified flow including some unnecessary simplifications. 

When the Blasius models for the shear stresses, Equations 12-14 are introduced into Equation 11, solutions for H, U, Uj, at steady conditions and the pressure drop can be obtained for a variety of two fluids, horizontal, or inclined two-phase stratified flows (Brauner and Moalem Maron [20]). 

Rovinsky et al. compared the solutions for laminar-laminar stratified flows obtained via the exact model with those predicted by the two-fluid model. Equations 11-14 [12] It was found that the error in H/D is bounded by 2.5%, and a typical error in the system pressure drop is about 10%. The comparison shows that for laminar-laminar flows, in the range of 0.1 < < 10 and 10" < xyiJ < 10, the accuracy... 

Biswas et al. [1988] developed a stratified flow model to predict the two phase pressure drop in trickle beds. The wetting of the packing depends on the... 

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