Experimental studies on drag reduction by coupled addition of nonionic polymer poly(ethylene oxide) and cationic surfactant cetyltrimethyl ammonium chloride

Abstract

More and more attention is paid to the synergistic drag reduction by polymers and surfactants because there are serious disadvantages of the drag reduction by them alone. In order to understand the synergistic effect of the drag reduction by polymers and surfactants, in-depth investigations are performed on the drag reduction behavior by simultaneous addition of nonionic polymer poly(ethylene oxide) (PEO) and cationic surfactant cetyltrimethyl ammonium chloride (CTAC) in a two-dimensional channel flow. The sodium salicylate (NaSal) is added to provide counter ions for promoting micelle formation. For comparisons, the drag-reducing behaviors of PEO and CTAC/NaSal alone are also investigated. The present results show that the synergistic effect of the drag reduction depends upon concentration combination of PEO and CTAC/NaSal. The Reynolds number range with a high drag-reducing rate becomes wider due to the simultaneous addition of PEO & CTAC/NaSal, whereas the ultimate drag reduction rate has a minimal change. The drag reduction enhancement is a complicated and nonlinear issue, and it seems that PEO and CTAC/NaSal play different roles in the drag reduction in different Reynolds number ranges.

Synthesis and performance evaluation of a new drag reducer based on acrylamide/12‐allyloxydodecyl acid sodium

“…Grafting a short branch on the main chain of the polymer can reduce the drag reduction performance while grafting a small number of long branches can improve the drag reduction effect 31 . The introduction of a hydrophobic polymerizable surfactant group into the main chain of a hydrophilic polymer molecule could give the polymer friction resistance, and reduce interfacial tension on the oil–water surface 11 . This approach could produce molecule properties similar to those of a surfactant.…”

“…31 The introduction of a hydrophobic polymerizable surfactant group into the main chain of a hydrophilic polymer molecule could give the polymer friction resistance, and reduce interfacial tension on the oil-water surface. 11 This approach could produce molecule properties similar to those of a surfactant. On the other hand, the hydrophobic surfactant groups, driven by "entropy" in water, could gradually associate to form a supramolecular network structure under the influence of intermolecular interactions such as hydrogen bonds, ion bonds and van der Waals forces, including the hydrogen bond supramolecular aggregation state, 14 (Figure 2).…”

“…Researches have shown that the combination of water‐soluble polymers and surfactants can retain the advantages of the individual materials, ameliorate their shortcomings, and improve overall drag reduction efficiency 9,10 . In different flow regimes, polymers and surfactants play different roles in the drag reduction process 11 . A bead mode was proposed along with an electrophoretic method to study the complex interaction of a surfactant and a polymer 12 .…”

“…9,10 In different flow regimes, polymers and surfactants play different roles in the drag reduction process. 11 A bead mode was proposed along with an electrophoretic method to study the complex interaction of a surfactant and a polymer. 12 A drag reduction experiment utilizing a polyacrylic acid (PAA) aqueous solution with sodium dodecyl sulfate (SDS) surfactant showed that the high elongation structure is more effective to drag reduction than the compact spiral structure.…”

Effects of oilfield injection water component on rheological characteristics of CTAC/NaSal aqueous solution

“…The commonly used drag reduction agents can be divided into polymer and surfactant, each of which has its own advantages and disadvantages (see Table 2). 9,10 Because surfactant can overcome the shortcomings of polymer and have reversibility of degradation, it is favored in the field of turbulent drag reduction. Many scholars have carried out amounts of research on the drag reduction characteristics and drag reduction mechanism of surfactant and found that the drag reduction mechanism of surfactant is closely related to its rheological characteristics 11 .…”