Holdup and pressure drop for two‐phase slug flow in inclined pipelines

Abstract

The simultaneous flow of gas and liquid in pipes is frequently encountered in industry. Consequently, considerable effort has been expended in developing reliable techniques for calculating holdup and pressure drop for gasliquid flow. Most of the recent work has concentrated on either vertical or horizontal flow. However, in some industrial environments, notably oil-and gas-gathering systems, flow is neither vertical nor horizontal.In this paper we present some results from a recent study of gas-liquid flow in pipelines inclined f 10 deg. from the horizontal. We shall concentrate our attention on the slug-flow regime because we found this regime to predominate in uphill and horizontal flows for conditions typicaliy encountered in pipeline applications. Stratified flow tends to dominate in the downhill situation but even for this pipeline orientation, slug flow can exist if the flow rate is sufficiently large.At the outset of this study it was decided that a fundamental approach would probably have the greatest potential for skcess. Therefore an extensive review was made of the two-phase literature in order to determine (1) the flow regimes encountered in two-phase flow and (2) the types of models proposed for these regimes. On'the basis of this information it was possible to develop the model for slug flow in inclined pipelines described in the next section. This model provided a guide for selecting the operating conditions in an 80-ft. test section. By judiciously combining our experimental and theoretical information, we developed correlations which were successfully validated against field data. We believe that this test of our correlations demonstrates the viability of a fundamental approach to an otherwise complex problem.

Translational velocities of elongated bubbles in continuous slug flow

“…The maximum in the drift velocity observed at 40°< b < 60°was explained qualitatively by Bonnecaze et al (1971). They argued that the gravitational potential that drives the liquid velocity along the curved surface at the bubble nose first increases and then decreases as the angle of inclination varies from the vertical towards the horizontal position.…”

The relation between the Taylor bubble motion and the velocity field ahead of it

“…Alves et al (1993) extended Benjamin's approach to the inclined and vertical cases, taking into consideration surface tension eects. Experimental studies on the drift velocity in inclined pipes as well as in vertical and horizontal pipes were performed by Singh and Grith (1970), Bonnecaze et al (1971), andBendiksen (1984).…”

Correlation and prediction of gas‐liquid holdups in inclined upflows

“…Articles have appeared by Mamaev ( 1965), Gallyamov andGoldzberg ( 1967, 1968), ISUPOV and llamaev ( 1968), and Guzhov et al (1967), representing a sizable research effort in this area. Similarly, a number of American works, such as those by Bonnecaze et al ( 1969Bonnecaze et al ( , 1971, Greskovich (1972), Bonderson ( 1969), and many contributions by Griffith et a]. (1971,1973), have also considered the subject of inclined two-phase flows.…”

“…A particular method for correlating actual liquid holdup with flowing liquid quality has been discussed by most of the above Russian investigators and expanded upon by Greskovich et al ( 1969), Greskovich and Shrier ( 1971), and Greskovich (1972). The correlation utilizes only mixture Froude number as a parameter and has been shown by Greskovich and Shrier (1971) to be quite accurate for horizontal flows, The only reported use of such a correlation for inclined flows is made by Guzhov et a].…”