Pressure drop and holdup predictions in horizontal oil–water flows for curved and wavy interfaces

The search for lower cost materials that reduce pressure drop in fluid transport systems in oil and gas industries to conserve pumping energy is of paramount importance. Polymers are known to reduce pressure drop in pipeline oil-water flows in a process referred to as drag reduction (DR). The effect of partially hydrolysed polyacrylamide, polyethylene oxide, Aloe Vera mucilage and their mixtures as drag reducing polymers (DRPs) on pressure gradient (pressure drop; Δp) in pipeline oil-water flows were studied. The experiment was carried out in flow rig with 0.02-m diameter straight unplasticised polyvinylchloride (uPVC) pipe, two centrifugal pumps, control valves and two storage tanks. Tap water (ρ = 997 kg/m3 and µ = 0.89 cP) and diesel (ρ = 832 kg/m3 and µ = 1.66 cP) were used as the test fluid at ambient condition. The polymer mixture total concentration (MTC) of 30 and 400 ppm at different mixing proportion, mixture Reynolds number (Remix) and oil input volume were investigated. The results show increase in pressure gradient with increase in oil input volume in both single-phase water flow and oil-water flow before adding drag reducing polymers (DRPs). However, Δp decreased after adding DRPs with increase in Reynolds number (Re) or Remix and decrease in the oil-phase Re, and vice versa. The results further showed higher reduction in pressure drop by the polymer mixture than in each of the polymer used at the same conditions. The rigidness of the biopolymer was improved by adding synthetic polymers which resulted to increase in DR efficiency.

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Prediction of pressure drop for segregated oil-water flows in small diameter pipe using modified two-fluid model

Experimental Thermal and Fluid Science ◽

10.1016/j.expthermflusci.2020.110078 ◽

2020 ◽

Vol 114 ◽

pp. 110078

Author(s):

Lusheng Zhai ◽

Hongxin Zhang ◽

Ningde Jin

Keyword(s):

Pressure Drop ◽

Fluid Model ◽

Small Diameter ◽

Water Flows ◽

Diameter Pipe ◽

Oil Water ◽

Two Fluid Model ◽

Two Fluid

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Parametric study of a model for determining the liquid flow-rates from the pressure drop and water hold-up in oil–water flows

International Journal of Multiphase Flow ◽

10.1016/j.ijmultiphaseflow.2007.07.003 ◽

2007 ◽

Vol 33 (12) ◽

pp. 1365-1394 ◽

Cited By ~ 14

Author(s):

M. Hadžiabdić ◽

R.V.A. Oliemans

Keyword(s):

Pressure Drop ◽

Liquid Flow ◽

Parametric Study ◽

Flow Rates ◽

Water Flows ◽

Oil Water

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Flow pattern and pressure drop for oil–water flows in and around 180° bends

SN Applied Sciences ◽

10.1007/s42452-020-04031-z ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Paul Onubi Ayegba ◽

Lawrence C. Edomwonyi-Otu ◽

Abdulkareem Abubakar ◽

Nurudeen Yusuf

Keyword(s):

Pressure Drop ◽

Pressure Gradient ◽

Flow Pattern ◽

Phase Inversion ◽

Superficial Velocity ◽

Pressure Losses ◽

Water Flows ◽

Oil Water ◽

Velocity Pressure ◽

Mixture Velocity

AbstractPressure drop and flow pattern of oil–water flows were investigated in a 19-mm ID clear polyvinyl chloride pipe consisting of U-bend with radius of curvature of 100 mm. The range for oil and water superficial velocities tested was $$0.04 \le U_{{{\text{so}}}} \le 0.950 \;{\text{m/s}}$$ 0.04 ≤ U so ≤ 0.950 m/s and $$0.13 \le U_{{{\text{sw}}}} \le 1.10 \;{\text{m/s}}$$ 0.13 ≤ U sw ≤ 1.10 m/s , respectively. Measurements were carried out under different flow conditions in a test section that consisted of four different parts: upstream of the bend, at the bend and at two redeveloping flow locations after the bend. The result indicated that the bend had limited influence on downstream flow patterns. However, the shear forces imposed by the bend caused some shift flow pattern transition and bubble characteristics in the redeveloping flow section after the bend relative to develop flow before the bend. Generally, pressure gradient at all the test sections increased with both oil fraction and water superficial velocity and there was a sharp change of pressure gradient profile during phase inversion. The transition point where phase inversion occurred was always within the range of $$0.4 \le U_{{{\text{sw}}}} \le 0.54 \;{\text{m/s}}$$ 0.4 ≤ U sw ≤ 0.54 m/s . Pressure losses differed at the various test sections, and the difference was strongly linked to the superficial velocity of the phases and the flow pattern. At high mixture velocity, pressure losses at the redeveloping section after the bend were higher than that at the bend and that for fully developed flows. At low mixture velocity, pressure losses at the bend are higher than in the straight sections. Pressure drop generally decreased with level of flow development downstream of the bend.

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Flow Pattern and Pressure Drop for Oil-Water Flows in and around 180° Bends

10.20944/preprints202005.0278.v1 ◽

2020 ◽

Author(s):

Paul Onubi Ayegba ◽

Lawrence C. Edomwonyi-Otu ◽

Abdulkareem Abubakar ◽

Nurudeen Yusuf

Keyword(s):

Pressure Drop ◽

Pressure Gradient ◽

Flow Pattern ◽

Phase Inversion ◽

Superficial Velocity ◽

Pressure Losses ◽

Water Flows ◽

Oil Water ◽

Velocity Pressure ◽

Mixture Velocity

Pressure drop and flow pattern of oil-water flows were investigated in a 19 mm ID clear polyvinyl chloride pipe consisting of U-bend with radius of curvature of 100 mm. The range for oil and water superficial velocities tested were and respectively. Measurements were carried out under different flow conditions in a test section that consisted of four different parts: upstream of the bend, at the bend and at two redeveloping flow locations after the bend. The result indicated that the bend had limited influence on downstream flow patterns. However, the shear forces imposed by the bend caused some shift flow pattern transition and bubble characteristics in the redeveloping flow section after the bend relative to develop flow before the bend. Generally, pressure gradient at all the test sections increased with both oil fraction and water superficial velocity and there was a sharp change of pressure gradient profile during phase inversion. The transition point where phase inversion occurred was always within the range of . Pressure losses differed at the various test sections and the difference was strongly linked to the superficial velocity of the phases and the flow pattern. At high mixture velocity, pressure losses at the redeveloping section after the bend were higher than that at the bend and that for fully developed flows. At low mixture velocity, pressure losses at the bend are higher than in the straight sections. Pressure drop generally decreased with level of flow development downstream of the bend.

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