Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Drag reduction


An Overview on Most Effective DRAs in Crude Oil Pipelines

Raheeq I. Ibrahim; Manal K. Odah; Dhoha A. Shafeeq

Engineering and Technology Journal, 2019, Volume 37, Issue 10A, Pages 391-397
DOI: 10.30684/etj.37.10A.2

The flow of crude oil in pipelines suffers from a problem of fluid flow pressure drop and high-energy consumption for pumping especially in low temperatures environment. Flow can be enhanced using viscosity either reduction or drag reduction techniques. Drag reduction is considered as the most effective and most applicable method. The technique contributes in reducing the frictional energy losses during the flow by addition of little doses of materials knowing as drag-reducing agents. The present work focuses on more recent and most applicable drag-reducing agents used in crude oil flow enhancement via pipelines.

Experimental Study of Drag Reduction Phenomena within Pipe Flow in a Closed Circuit System Using Surfactant Additives

S. A. Alramadhni; N. J. Saleh; G. A.R. Rassol

Engineering and Technology Journal, 2013, Volume 31, Issue 18, Pages 1-13

Pipe lines and tubes are used throughout the worlds for the economic transportation of crude oil, petroleum derivatives, gas and water. A drag reduction phenomenon within pipe flow in a closed circuit system was studying experimentally using Surfactant Additives.
Closed circuit system consist of two loops pipes (0.0254 m & 0.0508 m) ID respectively was constructed from carbon steel metal , total length of pipe was around 16 m and the test section was 4m. Similar closed circuit system consist of two loops of PVC pipes with the same diameters were also built. The idea of using PVC pipe was to be used inside carbon steel pipe to get smooth surface similar to using complaint coating like epoxy or polyethylene or poly vinyl chloride (PVC).
The effect of using two kinds of Anionic and Nonanionic surfactants (SDBS, POEA) Sodium Dodecyl Benzene Sulfonate and Polyoxyethylene Alcohol respectively were studied, Small amount of surfactant additives (50 ppm up to 300 ppm), were added to the solvent (kerosene) which was selected to be the fluid flow through the closed circuit system, choosing kerosene ( refinery product) to improve its flow (increasing flow rate).
A comparison between results obtained by carbon steel and PVC pipes were carried out. The best results obtained indicate that PVC pipe gave around (53% -66%) flow rate increase in kerosene compared with flowing in carbon steel pipe. On addition of additives for SDBS in kerosene improved flow rate about (61% to 69%).

Effect of Riblets Geometry on Drag Reduction

Nibras M. Mahdi; Ikhlase M. Fayed

Engineering and Technology Journal, 2010, Volume 28, Issue 22, Pages 6518-6535

The effect of longitudinal riblet surface models (U, V and semi-Circular and U with fillet corner riblets) on the performance of unsymmetrical airfoil (NACA23015) which has been investigated numerically and experimentally. Numerical investigation involve examining drag reduction by solving the governing equations (Continuity and Navier-Stokes equations) using the known package FLUENT version (6.1) in turbulent regime with appropriate turbulence model (κ-ε). Also measurement in experimental work will be carried out. The results indicate that the riblet surface models are the key parameters for controlling the boundary layer characteristic. The most effective riblet surface is U-riblet with fillet model (Mo.4, h=0.1mm), by compare to smooth model, the results show a small increment in lift slope curve about (9%) and total drag decrease (12%) over the angles of attack range from (0° to 17°).