Influence of Hydrophilicity on the Thermal-Driven Surfactant Flow at the Air/Water Surface

Nguyen, Trung B.; Phan, Chi

doi:10.1021/acsomega.8b00733

Cited by 3 publications

(4 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Surface tension (σ ) can be defined as the required energy to increase the area of an interface per unit area (σ = ∂ E/∂ A). It is known that surface tension depends on the temperature and on the concentration of some species 18 . In particular, some big molecules, known as surfactants, that have a hydrophobic tail and a hydrophilic head, adsorb at air-water or oil-water interfaces.…”

Section: A Theoretical Framementioning

confidence: 99%

Effect of insoluble surfactants on a thermocapillary flow

et al. 2021

View full text Add to dashboard Cite

The thermocapillary effect, arising flow due to a temperature gradient along a fluid interface, is the dominant effect in some industrial and microfluidic processes and must be studied in order to optimize them. In this work, we analyze how insoluble surfactants adsorbed at the interface can affect such a flow. In particular, we analyze the case where the thermocapillary flow is induced at the air-water interface by locally heating it with an infrared laser, setup that is used to manipulate floating particles through the generated flow.Since water is a polar fluid, the air-water interface is easily polluted by surfactants. We developed a numerical model considering the uncontrolled presence of surfactants, which evidences that the effect of the surface contamination cannot be neglected, even for small surfactants concentration. The results of this numerical model were compared with different experimental measurements: particle tracking velocimetry, convection cell radius measurements and thermography of the surface. All the experimental observations agree with the numerical model with the initial surface contamination being a fitting parameter. The model was then validated comparing its results with measurements for which a known quantity of surfactant was added to the interface. Finally, an analytical model was developed to explain the effects of the governing parameters, which agrees with the simulations and the experimental results. The developed models give us insights towards the miniaturization of the manipulation platform.

show abstract

Section: A Theoretical Framementioning

confidence: 99%

Effect of insoluble surfactants on a thermocapillary flow

et al. 2021

View full text Add to dashboard Cite

show abstract

“…The Euler–Lagrange model is used to calculate the two-phase flow, where one of the phases is dispersed, the volume fraction of the dispersed phase is less than 0.1 . The Euler–Euler model is useful for describing the double continuous two-phase flow, and it includes the Euler model, mixture model, VOF model, and other interface capture models. , In the present study, the gas–liquid two-phase flow does not have a stable continuous interface between gas and liquid, and the dispersed phase exhibits the phenomenon of coalescence and broken . Therefore, the Euler model and mixture model are much more suitable for the calculation of the gas–liquid two-phase flow and separation behaviors in multiple T-junctions. Euler model In the Euler model, the governing equations include continuity and momentum equations for each phase that should be solved in the multiphase flow.…”

Section: Numerical Methods and Multiphase Flow Modelsmentioning

confidence: 96%

“… 23 , 24 In the present study, the gas–liquid two-phase flow does not have a stable continuous interface between gas and liquid, and the dispersed phase exhibits the phenomenon of coalescence and broken. 25 Therefore, the Euler model and mixture model are much more suitable for the calculation of the gas–liquid two-phase flow and separation behaviors in multiple T-junctions. Euler model In the Euler model, the governing equations include continuity and momentum equations for each phase that should be solved in the multiphase flow.…”

Section: Numerical Methods and Multiphase Flow Modelsmentioning

confidence: 99%

Investigation of the Gas–Liquid Two-Phase Flow and Separation Behaviors at Inclined T-Junction Pipelines

Zhang

Liu

et al. 2020

ACS Omega

View full text Add to dashboard Cite

The T-junction is a novel type of separator used in the petroleum and gas industry. It is used to achieve the gas–liquid or liquid–liquid two-phase separation. To obtain an applicative T-junction separator, in the present study, the gas–liquid two-phase separation characteristics in multiple inclined T-junctions were investigated through a series of numerical simulations and field experiments. Two representative multiphase modes, namely, the Euler model and the mixture model, were chosen for this study. Comparisons of the field experiments were made to obtain a highly accurate simulation model. The mixture model was chosen to be better suited for this study. It is used to investigate the gas–liquid two-phase flow and the separation behaviors, which include the effect of inlet flow velocity, inlet bubble diameter, and the split ratio of two outlets. The results indicate that the best flow split ratio exists when the two-phase separation reaches the best consequence, and the best flow split ratio changes when the separation demands of gas or liquid are different. Furthermore, the separation efficiency keeps decreasing as the inlet velocity is increased. Hence, the inlet mixture velocity should be reduced to improve the gas–liquid two-phase separation. More specifically, to obtain a better separation for the same throughput, the size of the T-junction should be increased. Moreover, the separation efficiency increases as the inlet bubble diameter increases. Consequently, the results can be used to design the T-junction as an industrial separator, which can then be directly used in petroleum and gas production.

show abstract

“…At a molecular level, the hydrophilicity is controlled via a multiple intermolecular H-bonds network between the EO groups and water (Kaiser et al, 2016), which could give complicated responses upon heating/cooling. Hence, quantifying the thermal response of surfactants with different hydrophilicity is important for application purposes (Nguyen and Phan, 2018).…”

Section: Introductionmentioning

confidence: 99%

Influence of Temperature on the Surface Tension of Triton Surfactant Solutions

Nguyen

Phan

2018

J Surfact & Detergents

Self Cite

View full text Add to dashboard Cite

The surface tension of different Triton surfactants (X-100, X-405, and X-705) with or without adding sodium chloride was measured in the temperature range between 20 and 40 C using the maximum bubble pressure method. Rising temperature reduced the surface tension of Triton surfactants via disrupting the H-bonds between the ethylene oxide (EO) group and water. Increasing the number of the EO groups created the steeper thermal gradient of the surface tension. The data indicated that EO-water bonds are easier to be broken by rising temperature than the water-water H-bonds, with an entropy change of −0.535 J deg −1 per mole of EO. The presence of NaCl decreased the surface tension for all systems. However, NaCl produced a synergistic effect with surfactants on the surface tension.Keywords Surface tension Á Thermal effect Á Triton surfactants J Surfact Deterg (2019) 22: 229-235.

show abstract

Influence of Hydrophilicity on the Thermal-Driven Surfactant Flow at the Air/Water Surface

Cited by 3 publications

References 32 publications

Effect of insoluble surfactants on a thermocapillary flow

Effect of insoluble surfactants on a thermocapillary flow

Investigation of the Gas–Liquid Two-Phase Flow and Separation Behaviors at Inclined T-Junction Pipelines

Influence of Temperature on the Surface Tension of Triton Surfactant Solutions

Contact Info

Product

Resources

About