Drag-reduction behavior of an unusual nonionic surfactant in a circular pipe turbulent flow

Cai, Shibo; Higuchi, Yuta

doi:10.1016/s1001-6058(14)60045-7

Cited by 12 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The surfactant used in the present experiments was cetyltrimethyl ammonium bromide (CTAB), which was mixed with sodium salicylate as a counterion in a molar ratio of 1:2 (surfactant to counterion) at 60 and 100 ppm by weight. This molar ratio was confirmed to be favorable for reducing turbulent drag as reported in the previous study . Before being mixed, they were separately dissolved in deionized water.…”

Section: Experimental Apparatus and Proceduressupporting

confidence: 72%

“…For surfactant and polymer aqueous solutions, their drag-reducing behaviors are obviously different due to their different rheological properties. [13][14][15][16] A significant difference in rheological characteristics is the formed micellar superstructure induced by shear flow, which finally results in a viscoelasticity for a drag-reducing surfactant solution when shear rate exceeds a critical one. This micellar structure is widely thought to be vital for drag reduction in turbulent flows.…”

Section: Introductionmentioning

confidence: 99%

“…This micellar structure is widely thought to be vital for drag reduction in turbulent flows. [13][14][15][16][17][18] Moreover, it was found to be helpful for the turbulence suppression 13,[19][20][21] and modification of the turbulence structures, such as the shear stress distribution in the flow cross section, the low speed streaks and quasistreamwise vortices 19,20 in turbulent channel, and circular pipe flows of a surfactant or polymer solution.…”

Section: Introductionmentioning

confidence: 99%

“…A significant difference in rheological characteristics is the formed micellar superstructure induced by shear flow, which finally results in a viscoelasticity for a drag‐reducing surfactant solution when shear rate exceeds a critical one. This micellar structure is widely thought to be vital for drag reduction in turbulent flows . Moreover, it was found to be helpful for the turbulence suppression and modification of the turbulence structures, such as the shear stress distribution in the flow cross section, the low speed streaks and quasistreamwise vortices in turbulent channel, and circular pipe flows of a surfactant or polymer solution.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Drag reduction of a zero‐pressure gradient boundary layer flow by surfactants

Cai

Wang

Duan

2018

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

To investigate drag reduction by a surfactant in a zero‐pressure gradient flat‐plate turbulent boundary layer flow, the velocities were measured by a two‐component laser Doppler velocimeter, and the buildup as well as relaxation of micelle shear‐induced structures in a simple shear flow was then analyzed by a strain‐controlled rheometer through applying and releasing a given constant shear strain rate. The surfactant was cetyltrimethyl ammonium bromide mixed with sodium salicylate as a counterion in a molar ratio of 1:2 at 60 and 100 ppm by weight. It has been found that the drag reduction rate first increases and then decreases with decreasing wall shear stress in the streamwise direction for the two concentrations of solutions, which is totally different with that in a pipe flow. In addition, the drag reduction in a lower concentration solution boundary layer flow reaches the maximum earlier. Moreover, a shorter buildup time for the micelle shear‐induced structures makes the maximal drag reduction reach earlier in surfactant solution boundary layer flows.

show abstract

Section: Experimental Apparatus and Proceduressupporting

confidence: 72%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Drag reduction of a zero‐pressure gradient boundary layer flow by surfactants

Cai

Wang

Duan

2018

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

show abstract

“…Flow enhancement (drag reduction) in pipelines attracts the attention of many researchers around the globe due to its high academic and industrial impact [1][2][3][4][5][6]. Over the past few decades, several drag reduction techniques were introduced and experimentally investigated in different applications such as in the Alaskan pipeline [7][8][9], the transportation of suspensions and slurries, in marine systems and medical fields [10,11].…”

Section: Introductionmentioning

confidence: 99%

Biopolymer–Surfactant Complexes as Flow Enhancers: Characterization and Performance Evaluation

et al. 2019

View full text Add to dashboard Cite

Artificial polymeric additives are known, and experimentally proven, to be effective drag reducing agents in pipelines with turbulent flow medium. The artificial nature of these additives and their low resistance to high shear forces, exerted by the pipeline geometries and equipment, are considered as major problems against a wider implementation in other industrial applications. The present work introduces a new polymer-surfactant complex of two organic additives (chitosan and sodium laurel ether sulfate, SLES) as a drag reducing agent. The rheological and morphological properties of the new complexes were experimentally tested. The new complex’s drag reduction performance and stability against high shear forces were analyzed using rotating disk apparatus. All the investigated solutions and complexes showed a non-Newtonian behavior. The cryo-TEM images showed a unique polymer-surfactant macrocomplex structure with a nonlinear relationship between its rheological properties and surfactant concentration. A maximum flow enhancement of 47.75% was obtained by the complex (chitosan 300 and 400ppmof chitosan and SLES, respectively) at the rotation speed of 3000 rpm. Finally, the stability of the proposed additives was highly modified when the additive complexes were formed.

show abstract