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We apply principles of Gibbs phase plane chemistry across the entire ocean-atmosphere interface to investigate aerosol generation and geophysical transfer issues. Marine surface tension differences comprise a tangential pressure field controlling trace gas fluxes, primary organic inputs, and sea spray salt injections, in addition to heat and momentum fluxes. Mapping follows from the organic microlayer composition, now represented in ocean system models. Organic functional variations drive the microforcing, leading to (1) reduced turbulence and (by extension) laminar gas-energy diffusion; plus (2) altered bubble film mass emission into the boundary layer. Interfacial chemical behaviors are, therefore, closely reviewed as the background. We focus on phase transitions among two dimensional “solid, liquid, and gaseous” states serving as elasticity indicators. From the pool of dissolved organic carbon (DOC) only proteins and lipids appear to occupy significant atmospheric interfacial areas. The literature suggests albumin and stearic acid as the best proxies, and we distribute them through ecodynamic simulation. Consensus bulk distributions are obtained to control their adsorptive equilibria. We devise parameterizations for both the planar free energy and equation of state, relating excess coverage to the surface pressure and its modulus. Constant settings for the molecular surrogates are drawn from laboratory study and successfully reproduce surfactant solid-to-gas occurrence in compression experiments. Since DOC functionality measurements are rare, we group them into super-ecological province tables to verify aqueous concentration estimates. Outputs are then fed into a coverage, tension, elasticity code. The resulting two dimensional pressure contours cross a critical range for the regulation of precursor piston velocity, bubble breakage, and primary aerosol sources plus ripple damping. Concepts extend the water-air adsorption theory currently embodied in our OCEANFILMS aerosol emissions package, and the two approaches could be inserted into Earth System Models together. Uncertainties in the logic include kinetic and thermochemical factors operating at multiple scales.

As exploration and development enter the deep, deep, and unconventional era, micro annular gaps have become the main form of failure in the integrity of cement sheath seals. Therefore, accurate prediction of micro annular gap damage at the cement sheath interface under continuous internal pressure changes is a prerequisite for ensuring drilling safety. However, in the traditional analysis of the integrity of the cement sheath, the initial state and interfacial bonding effect of the cement sheath are often overlooked. In this paper, we propose a model that includes these effects to quantitatively analyse the degree of micro annular damage at the interface of the cement sheath. We propose an empirical model using measured values for interface bonding strength. The degree of micro annular damage at the cement sheath interface under internal pressure changes is evaluated through a fully coupled transient elastoplastic model. The results indicate that the damage to the cement sheath interface is determined by both the loading and unloading processes of pressure inside the pipe. The loading process may cause the cement sheath to enter plasticity, while the decrease in internal pressure during unloading will result in interface tension, leading to micro ring gaps. Both the first and second interfaces may generate micro annular gaps, depending on the relationship between interface bonding strength and interface tension. Due to the fact that the tensile force at the first interface of the cement sheath is greater than that at the second interface during the unloading process, the degree of micro annular damage at the first interface is higher.

Conventional water-based fracturing treatments may not work well for many shale gas reservoirs. This is due to the fact that shale gas formations are much more sensitive to water because of the significant capillary effects and the potentially high contents of swelling clay, each of which may result in the impairment of productivity. As an alternative to water-based fluids, gaseous stimulants not only avoid this potential impairment in productivity, but also conserve water as a resource and may sequester greenhouse gases underground. However, experimental observations have shown that different fracturing fluids yield variations in the induced fracture. During the hydraulic fracturing process, fracturing fluids will penetrate into the borehole wall, and the evolution of the fracture(s) then results from the coupled phenomena of fluid flow, solid deformation and damage. To represent this, coupled models of rock damage mechanics and fluid flow for both slightly compressible fluids and CO2 are presented. We investigate the fracturing processes driven by pressurization of three kinds of fluids: water, viscous oil and supercritical CO2. Simulation results indicate that SC-CO2-based fracturing indeed has a lower breakdown pressure, as observed in experiments, and may develop fractures with greater complexity than those developed with water-based and oil-based fracturing. We explore the relation between the breakdown pressure to both the dynamic viscosity and the interfacial tension of the fracturing fluids. Modeling demonstrates an increase in the breakdown pressure with an increase both in the dynamic viscosity and in the interfacial tension, consistent with experimental observations.

Classical Molecular Dynamics simulations were used to investigate the interfacial adsorption of supercritical ethane on ultrathin molten polyethylene films at various temperatures (298.15–448.15 K) and pressures (0.28–13.17 MPa). Ethane was found to accumulate preferentially at the film’s interfaces rather than dissolving into the film’s core. The ultra-thin, metastable films, studied at their mechanical stability limit, are composed of two overlapping interfaces. The films show some fractions of interfacial chains transiently desorbing from the film surface and entering the gas phase, which facilitates the accumulation of ethane at the interfaces. At 373.15 K and pressures between 0.29 MPa and 9.65 MPa, the combined film interfaces adsorb between 4.8 and 8.6 times more ethane than the amount solubilized in the central, bulk region of the film. Interfacial tension of the film decreases exponentially with increasing gas pressure of ethane and is primarily governed by inter-chain interactions at the interface. Minor contributions arise from the vibrational dynamics of polyethylene chain fractions that transiently desorb from the film surface. Furthermore, the solubility of ethane in the film’s bulk region exhibits a temperature-dependent inversion: at 298.15 K, the ethane density in the film’s center slightly exceeds that of the bulk gas, but this trend reverses at 373.15 K and becomes more pronounced as the temperature increases. This indicates a potential solubility transition temperature between 298.15 K and 373.15 K.

CO2/N2 injection in heavy oil reservoirs has been demonstrated to enhance oil recovery (EOR) and facilitate CO2 capture, utilization, and storage (CCUS). Interfacial tension (IFT) is a crucial parameter for characterizing oil recovery, but it can be influenced by real-time changes in reservoir pressure and temperature during gas injection. The impact of the CO2/N2 ratio on the oil–gas IFT under varying temperature and pressure conditions remains unclear. Therefore, a systematic study was conducted to investigate the effects of multiple parameters on the oil–gas IFT during development processes, and a three-dimensional (3D) database and a regression model of IFT were established using experimental data. The results show that IFT is strongly correlated with density difference, moderately correlated with pressure and CO2 proportion, weakly correlated with saturates content and resin content, and nonlinearly correlated with temperature, aromatics content, and asphaltene content, respectively. Moreover, it has been observed that an increase in pressure or CO2 proportion can lead to a reduction in IFT. However, the impact of temperature changes on IFT varies across different pressure ranges. We introduce a new parameter, the equivalent interfacial tension pressure during temperature changes (EITP), to characterize this effect and discuss the reasons for the emergence of EITP, providing new insight into optimizing the CO2/N2 injection ratio in the reservoir. This study aims to reveal the advantages of oil–gas interface characteristics under the influence of multiple parameters in promoting low-carbon and efficient development of heavy oil reservoirs, and to explore the significance of CO2/N2 for enhancing heavy oil recovery. [Display omitted]

A uniform nanometric thin liquid film on a solid substrate can become unstable due to the action of van der Waals (vdW) forces. The instability leads to dewetting of the uniform film and the formation of drops. To minimize the total free energy of the system, these drops coarsen over time until one single drop remains. Here, using a thermodynamically consistent framework, we derive a new model for thin films in partial wetting with a free energy that resembles the Cahn–Hilliard form with a height-dependent surface tension that leads to a generalized disjoining pressure, and revisit the dewetting problem. Using both linear stability analysis and nonlinear simulations we show that the new model predicts a slightly smaller critical instability wavelength and a significantly (up to six-fold) faster growth rate than the classical model in the spinodal regime; this faster growth rate brings the theoretical predictions closer to published experimental observations. During coarsening at intermediate times, the dynamics become self-similar and model-independent; we therefore observe the same scalings in both the classical (with and without thermal noise) and new models. Both models also lead to a mean-field Lifshitz–Slyozov–Wagner (LSW)-type droplet-size distribution at intermediate times for small drop sizes. We, however, observe a skewed drop-size distribution for larger drops in the new model; while the tail of the distribution follows a Smoluchowski equation, it is not associated with a coalescence-dominated coarsening, calling into question the association made in some earlier experiments. Our observations point to the importance of the height dependence of surface tension in the early and late stages of dewetting of nanometric films and motivate new high-resolution experimental observations to guide the development of improved models of interfacial flows at the nanoscale.

Accurate predictions of equilibrium, transport, and interfacial properties of H2S-brine systems play a significant role in improving acid gas sequestration efficiency in saline aquifers. In the current study, molecular dynamics (MD) simulations were used to simultaneously predict the interfacial tension (IFT), mutual solubility, viscosity, and density of the H2S-brine solutions to compensate for the lack of experimental data on these crucial properties. The effects of temperature, pressure, salt type and concentration on the properties influencing the storage process are investigated in the ranges of pressures up to 30 MPa, temperatures of 323.15–393.15 K, and salinities of 1–3 mol/kg, which represent typical conditions of acid gas geological storage. We employed mixed brine systems with the most common monovalent and divalent salts to study the impact of different ions on the desired properties with detailed microstructural insight. A comprehensive validation was performed to verify the accuracy of MD model by comparison with experimental data of the H2S-water and H2S-NaCl solutions. The average absolute deviations percent (AAD%) of 4.27, 5.20, 3.74, and 4.93% were obtained for reproducing the H2S solubility in water, H2S-rich phase water content, density, and IFT of the H2S-water system, respectively, close to the experimental uncertainties. The increasing ion concentration results in a decrease in the mutual solubilities and a linear increase in IFT values because of forming contact ion pairs, which is more remarkable in the CaCl2-containing solution. However, the salting-out effect is more pronounced for the solubility of H2S than water content. IFTs of the H2S-NaCl + CaCl2 (aq) are greater in comparison with those of H2S-NaCl + KCl (aq) solution, while this trend is reversed for mutual solubilities. The H2S dissolution reduces the density values of brine solutions compared to fresh brine, which has an unfavorable impact on the density-driven convective process and has the higher opposite effect on the viscosity values. The most effective parameters on the density and viscosity values are salinity and temperature, respectively, under our studied operating conditions.

Despite the extensive use of 2-propanol and acetone in a wide range of applications in the chemical industry and in energy engineering, there is a lack of experimental data in the literature for their thermophysical properties including viscosity, interfacial tension, and density, especially at elevated temperatures beyond the respective normal boiling points. In the present study, the liquid viscosity and interfacial tension were determined simultaneously by surface light scattering (SLS) with average expanded uncertainties of (1.7 and 0.9)% at or close to saturation conditions for temperatures between (273 and 403) K. Furthermore, capillary viscometry (CV) and vibrating-tube densimetry were employed to measure the liquid viscosity at ambient pressure of 0.1 MPa from (283 to 353) K and the liquid density close to saturation conditions between (278 and 423) K. The obtained density data were used for the evaluation of both SLS and CV experiments. In comparison with literature data, the present density data show agreement for 2-propanol over the entire temperature range. In contrast, deviations of up to 0.5% at the maximum temperature can be found for acetone. For the viscosity and interfacial tension at low temperatures, agreement of the measurement results among each other and with literature data is mostly found. At elevated temperatures, the increasing deviations of the present experimental viscosity and interfacial tension data from recommended correlations indicate a lack of reliable data needed for their development. Overall, this work contributes to an improvement of the database for viscosity, interfacial tension, and density of 2-propanol and acetone over a wide temperature range up to 423 K.

During spontaneous imbibition, a wetting liquid is drawn into a porous medium by capillary forces. In systems with comparable pore length and diameter, such as paper and sand, the front of the propagating liquid forms a continuous interface. Sections of this interface advance in a highly correlated manner due to an effective surface tension, which restricts front broadening. Here we investigate water imbibition in a nanoporous glass (Vycor) in which the pores are much longer than they are wide. In this case, no continuous liquid–vapor interface with coalesced menisci can form. Anomalously fast imbibition front roughening is experimentally observed by neutron imaging. We propose a theoretical pore-network model, whose structural details are adapted to the microscopic pore structure of Vycor glass and show that it displays the same large-scale roughening characteristics as observed in the experiment. The model predicts that menisci movements are uncorrelated, indicating that despite the connectivity of the network the smoothening effect of surface tension on the imbibition front roughening is negligible. These results suggest a new universality class of imbibition behavior, which is expected to occur in any matrix with elongated, interconnected pores of random radii.