Multicomponent Fluid Research Articles

Perspective on new implementations of atomtronic circuits

In this article, we provide perspectives for atomtronics circuits on quantum technology platforms beyond simple bosonic or fermionic cold atom matter-wave currents. Specifically, we consider (i) matter-wave schemes with multi-component quantum fluids; (ii) networks of Rydberg atoms that provide a radically new concept of atomtronics circuits in which the flow, rather than in terms of matter, occurs through excitations; (iii) hybrid matterwave circuits—a combination of ultracold atomtronic circuits with other quantum platforms that can lead to circuits beyond the standard solutions and provide new schemes for integrated matter-wave networks. We also sketch how driving these systems can open new pathways for atomtronics.

Framework for simulating the partially miscible multi-component hydrocarbon fluids in porous media via the pseudo-potential lattice Boltzmann model

framework for simulating the partially miscible multi-component hydrocarbon fluids in porous media via the pseudo-potential lattice Boltzmann model

Analysis of Adaptability and Application Potential of Supercritical Multi-Source Multi-Component Thermal Fluid Technology for Offshore Heavy Oil in China

Supercritical multi-source, multi-component thermal fluid is a heavy oil thermal recovery method independently developed by China National Offshore Oil Co., Ltd (Beijing, China). It uses waste liquid at the production end of the production well as the water source, the injection medium temperature exceeds 374 °C, 22.1 MPa, and all the produced flue gas is re-injected. Compared with steam huff and puff technology, supercritical technology has the advantages of high enthalpy value, high heat utilization rate, good oil displacement effect, and being green and pollution-free. In addition, its oil–water treatment cost is low, it can realize the reuse of organic matter, it has a good cost advantage of water treatment under the background of low carbon, and it is a thermal recovery method with great application potential for offshore heavy oil. Therefore, it is necessary to carry out research on the adaptability and application potential of supercritical multi-source, multi-heat flow thermal recovery technology in the sea. Based on the laboratory one-dimensional displacement experiment, this paper reveals the mechanism of heavy oil supercritical multi-source multi-component thermal fluid displacement and the contribution of supercritical components to the displacement effect, and establishes the supercritical multi-source, multi-component thermal fluid numerical simulation characterization method. Combined with the characteristics of offshore heavy oil reserves, the main control factors affecting supercritical multi-source, multi-component thermal fluid development were established by numerical simulation and orthogonal test methods, and the adaptive screening method of offshore supercritical technology was established. The application potential of 670 million tons of offshore heavy oil reserves was evaluated and sorted, and KL 10-2 oilfield was selected as the pilot test oilfield. The results show that supercritical technology has great advantages in oil displacement and water treatment cost reduction, and the results play an important guiding significance for the development of offshore heavy oil technology system and the iteration of new technology.

A novel simulated media system for in vitro evaluation of bioequivalent intestinal drug solubility

Orally administered solid drug must dissolve in the gastrointestinal tract before absorption to provide a systemic response. Intestinal solubility is therefore crucial but difficult to measure since human intestinal fluid (HIF) is challenging to obtain, varies between fasted (Fa) and fed (Fe) states and exhibits inter and intra subject variability. A single simulated intestinal fluid (SIF) cannot reflect HIF variability, therefore current approaches are not optimal. In this study we have compared literature Fa/FeHIF drug solubilities to values measured in a novel in vitro simulated nine media system for either the fasted (Fa9SIF) or fed (Fe9SIF) state. The manuscript contains 129 literature sampled human intestinal fluid equilibrium solubility values and 387 simulated intestinal fluid equilibrium solubility values. Statistical comparison does not detect a difference (Fa/Fe9SIF vs Fa/FeHIF), a novel solubility correlation window enclosed 95% of an additional literature Fa/FeHIF data set and solubility behaviour is consistent with previous physicochemical studies. The Fa/Fe9SIF system therefore represents a novel in vitro methodology for bioequivalent intestinal solubility determination. Combined with intestinal permeability this provides an improved, population based, biopharmaceutical assessment that guides formulation development and indicates the presence of food based solubility effects. This transforms predictive ability during drug discovery and development and may represent a methodology applicable to other multicomponent fluids where no single component is responsible for performance.

Mathematical modeling of concentration influence on evaporative convection in a bilayer system of binary mixtures

A problem of evaporative buoyancy-thermocapillary convection in a two-phase system of binary media is studied. Characteristics of a joint steady flow of evaporating fluid and gas in a narrow plane horizontal channel are analyzed on the example of aqueous ethanol solution and mixture of the nitrogen with the ethanol vapor. The influence of solutal effects related to changes in the ethanol concentration in the liquid mixture is scrutinized. New exact solution of thermosolutal convection equations is constructed in the framework of a two-sided model based on the Oberbeck–Boussinesque approximation. The model used implies the presence of the liquid–gas interface admitting evaporation where surface phenomena play a key role. The testing of problem statements is performed in order to determine feasible closing relations. A correct problem statement is proposed that provides acceptable accordance with known experimental data concerning both the working liquid properties and possible pattern of the bilayer flows. Non-linear character of dependence of evaporation rate on the concentration of the aqueous solution is established. The solution predicts the decrease in evaporation rate due to the diffusion resistance effect for some compositions of the liquid mixture, thereby it is shown the possibility of control of the heat exchange parameter by means of the choice of the working fluid compound. The results obtained can be useful under developing the experimental methods for exploration of the interfacial effects in multicomponent fluids.

Interfacial structure within thin films of decane isomers adsorbed on a metal substrate

Canonical-ensemble Monte Carlo simulations were used to examine the solid–liquid interfacial structure within neat and multicomponent solutions of decane isomers at 350 K. As seen both experimentally and computationally for many fluids, layering within the liquid film near the solid substrate was exhibited in all fluids examined here. The amount of branching within a molecule, though, limited the range of density oscillations, particularly for multicomponent fluids. Analysis of molecular orientation within the first layer showed a strong preference in most cases for molecules to adopt orientations that enhance the energy of adsorption. To this end, preferential absorption was observed in all fluid mixtures with n-decane present. For both n-decane and 2,2-dimethyloctane, whether neat or in solution, the preference for orientations that maximise interactions between the alkane backbone of the molecule and the substrate led to additional in-plane alignment between adjacent adsorbed molecules. In contrast, for 4-propylheptane little in-plane alignment or orientation preference was observed at the interface.

A two-phase, multi-component model for efficient CO2 storage and enhanced gas recovery in low permeability reservoirs

Introduction: Carbon dioxide (CO2) enhanced gas recovery represents a viable strategy for sequestering CO2 while concurrently augmenting gas production from subsurface reservoirs. Gas reservoirs, as inherent geological formations, are optimal repositories for gaseous compounds, rendering them suitable for CO2 storage. Nevertheless, the economic viability of pure CO2 storage necessitates integration with oil and gas recovery mechanisms to facilitate widespread CO2 utilization.Method: This study addresses the complexities of CO2 enhanced gas recovery through a comprehensive approach that combines theoretical model and numerical simulations. A numerical model is developed to simulate three-component diffusion involving CO2, and methane (CH4) in a two-phase system comprising gas and water.Results: The investigation systematically explores the process of enhanced CH4 extraction and CO2 injection into the reservoir and examines the influencing factors on extraction. Simulation results reveal a power-law decrease in CH4 production rate, stabilizing at a constant extraction rate. Enhanced CH4 extraction benefits from increased porosity, with higher porosity levels leading to greater CH4 extraction. Permeability augmentation positively influences CH4 production, although with diminishing returns beyond a certain threshold. The CO2 injection rate shows a direct proportionality to CH4 production. However, elevated CO2 injection rates may increase reservoir pressure, potentially causing cap rock damage and CO2 gas flushing.Discussion: This study contributes valuable theoretical insights to the field of CO2 enhanced gas recovery engineering, shedding light on the intricate dynamics of multi-component fluid transport processes and their implications for sustainable CO2 utilization.

The existence of a weak solution for a compressible multicomponent fluid structure interaction problem

We analyze a system of PDEs governing the interaction between two compressible mutually noninteracting fluids and a shell of Koiter type encompassing a time dependent 3D domain filled by the fluids. The dynamics of the fluids is modeled by a system resembling compressible Navier-Stokes equations with a physically realistic pressure depending on densities of both the fluids. The shell possesses a non-linear, non-convex Koiter energy. Considering that the densities are comparable initially we prove the existence of a weak solution until the degeneracy of the energy or the self-intersection of the structure occurs for two cases. In the first case the adiabatic exponents are assumed to satisfy max⁡{γ,β}>2, min⁡{γ,β}>0, and the structure involved is assumed to be non-dissipative. For the second case we assume the critical case max⁡{γ,β}≥2 and min⁡{γ,β}>0 and the dissipativity of the structure. The result is achieved in several steps involving, extension of the physical domain, penalization of the interface condition, artificial regularization of the shell energy and the pressure, the almost compactness argument, added structural dissipation and suitable limit passages depending on uniform estimates.

Exact Solutions to the Navier–Stokes Equations for Describing the Flow of Multicomponent Fluids with Internal Heat Generation

Exact Solutions to the Navier–Stokes Equations for Describing the Flow of Multicomponent Fluids with Internal Heat Generation

An all-Mach consistent numerical scheme for simulation of compressible multi-component fluids including surface tension, cavitation, turbulence modeling and interface sharpening on compact stencils

We present a numerical scheme valid in the range of highly to weakly compressible flows using a single-fluid four equation approach together with multi-component thermodynamic models. The approach can easily be included into existing finite volume methods on compact stencils and enables handling of compressibility of all involved phases including surface tension, cavitation and viscous effects. The mass fraction (indicator function) is sharpened in the two-phase interface region using the algebraic interface sharpening technique Tangent of Hyperbola for INterface Capturing (THINC). The cell face reconstruction procedure for mass fractions switches between an upwind-biased and a THINC-based scheme, along with proper slope limiters and a suitable compression coefficient, respectively. For additional sub-grid turbulence modeling, a fourth order central scheme is included into the switching process, along with a modified discontinuity sensor. The proposed “All-Mach” Riemann solver consistently merges the thermodynamic relationship of the components into the reconstructed thermodynamic variables (like density, internal energy), wherefore we call them All-Mach THINC-based Thermodynamic-Dependent Update (All-Mach THINC-TDU) method. Both, liquid-gas and liquid-vapor interfaces can be sharpened. Surface tension effects are taken into account by using a Continuum Surface Force (CSF) model. In order to reduce spurious oscillations at interfaces we decouple the computation of the interface curvature from the computation of the gradient of the Heaviside function. An explicit, four stage low storage Runge-Kutta method is used for time integration. The proposed methodology is validated against a series of reference cases, such as bubble oscillation/advection/deformation, shock-bubble interaction, a vapor/gas bubble collapse and a multi-component shear flow. The results of a near-critical shock/droplet interaction case are superior to those obtained by WENO3 and OWENO3 schemes and support that the proposed methodology works well with various thermodynamic relations, like the Peng-Robinson equation of state. Finally, the approach is applied to simulate the three-dimensional primary break-up of a turbulent diesel jet in a nitrogen/methane mixture including surface tension effects under typical dual-fuel conditions. The obtained results demonstrate that the methodology enables robust and accurate simulations of compressible multi-phase/multi-component flows on compact computational stencils without excessive spurious oscillations or significant numerical diffusion/dissipation.

Modeling Multicomponent Fluid Flow in Deforming and Reacting Porous Rock

Modeling Multicomponent Fluid Flow in Deforming and Reacting Porous Rock

Local Structure of Nonuniform Fluid Mixtures Containing Associating and Chainlike Molecules from a Multilayer Quasichemical Model.

In this work, we develop a theory for predicting details of the local structure in nonuniform multicomponent fluids that may contain chainlike and associating components. This theory is an extension─to the fluid interfaces and mesoscopic structures of different geometry─of the multilayer quasichemical model originally proposed by Smirnova to describe liquid solution in the vicinity of a planar solid wall. The basis of the theory is the "cut-and-bond" approach, much in spirit of SAFT, where an infinite attraction between the separated monomeric units of a chainlike molecule mimics the chemical bonds of the chain. We describe the equilibrium structure of the mixture, including the spatial distribution of the monomeric units and the local orientation of the chemical bonds in chainlike molecules, and discuss the contribution of chemical bonds to the local chemical potential in a nonuniform fluid. To test the new theory, we apply it to mixtures containing combinations of model components: a strongly associating solvent, an inert substance of varying chain length, and a chainlike amphiphile. To compare predictions from the multilayer model with the results of continuous description of nonuniform fluids, we also address the square-gradient theory and derive an analytical expression for the influence parameter that takes into account pair correlations in the quasichemical approximation. The multilayer quasichemical model developed in this work predicts formation of aggregates in liquid solution and describes the local structure of the interfaces between the coexisting liquid phases in the mixture. Our theoretical predictions agree on a qualitative level with the accumulated knowledge about the structure of different types of systems studied in this work.

Experimental study of CO2/O2 corrosion on pipelines during carbon capture, utilization and storage process

In this paper, high-temperature and high-pressure corrosion test was used to simulate the corrosion process of multi-component thermal fluid (CO2/O2/H2O) on oil pipes (N80 steel), casings (J55, TP90H, P110 steel, and transportation pipelines (20# steel) in the process of CCUS technology application. The results show that during the entire corrosion process, the oil layer casing and surface casing are corroded most seriously in this environment, and the corrosion forms of these five steel materials in the CO2/O2 environment are uniform corrosion and local corrosion, and the corrosion products mainly consist of FeCO3, Fe2O3, Fe3O4 and FeOOH crystals. These oxides form a double-layer film structure on the surface of the steel. The inner layer is denser and consists mostly of FeCO3 crystals, which has better protection against further corrosion of the internal steel. The outer layer is loose and porous, and its components are mostly FeCO3 crystals. Fe2O3, FeOOH, Fe3O4 and FeCO3 crystals, have poor corrosion protection for internal steel. Due to the difference in corrosion products of the inner and outer film layers, relatively obvious local corrosion appeared on the surfaces of the 5 steel materials.

A Cubic Equation of State with a Repulsion Term

A new cubic equation of state (EoS) was proposed to address the lack of repulsion terms in conventional cubic EoSs, with a molar critical compressibility factor Zc = 0.273 and suitable for most molecular fluids. Similar to Soave-Redlich-Kwong (SRK) EoS, its α-function is related to the fluids’ acentric factors by fitting with 44 molecular fluids. Differently, the new EoS can pass the α-consistency test, confirming the robustness across all temperatures. With only three parameters (ac, b, m) to be determined, it is as convenient as the SRK EoS in application. But it is more accurate - tested against experimental data - for both single and multi-component fluids than SRK EoS.

Visualization study on double-diffusive convection during a rollover in liquid energy storage tanks

The growing global energy consumption and the transition to the renewable era highlight the urgent need for safe and energy-efficient liquid energy storage tanks. Rollover has been a severe hazard to the efficiency and safety of the storage tank accompanied by significantly enhanced mass and heat transport across the stratified layers, and rapid evaporation and mixing of the layers happen. However there is a lack of experiments sophistically designed for cryogenic storage applications, which leads to a lack of visualized and quantitative experimental data to understand the physics of rollover in energy storage tanks. In this study, a Z-type Schlieren system is established to visually reveal the double-diffusive convection patterns in a cylindrical experimental chamber. The concentrations of salt-water solutions are adjusted to simulate the density difference between the multi-component cryogenic fluids. Cross-correlation algorithm is adopted to analyze the transient velocity distributions in the stratified system. The rollover process is divided into four stages, namely the initial, transition, mixing, and stable stages. Effects of heat flux, concentration difference, and heating location on the rollover characteristics are parametrically investigated. Correlations are proposed with rescaled buoyancy ratio and density gradient, and satisfactory agreement with experimental data is achieved.

On the Wave-Particle Duality of the Photons and the Matter-Photon Particle Mixture Model

Relativistic quantum mechanics and many experimental results and observations show that electron-positron annihilation can produce photons; photon-matter and photon-photon interaction can also create electrons and positrons. The photons have no rest mass, e.g. relative to Lab frame, and always travel at the speed of light in the vacuum. In this paper, a rotational moving electric dipole model with negative and positive charges was proposed for photons. In a vacuum, the electric dipoles are moving in a twisted helical motion around their propagation axis (their center of mass). Photon particles are traveling at the speed of light along the propagation axis. This pair of negative and positive charged particles exerts both electrostatic and magnetic force on each other. Both forces are attractive and act as a centripetal force to keep the electric dipole in a continuous helical motion around the axis of rotation. With this model, the wave-particle duality of photons can be described simultaneously. The space is filled by matter (having rest mass relative to Lab frame) and photons (without rest mass); it is a multicomponent mixture fluid. In "vacuum", though there is no rest matter particle, but there are still photon gas particles, the total energy-momentum tensor should include rest matter particles and photon gas particles.

Simulation study of hydrogen sulfide removal in underground gas storage converted from the multilayered sour gas field

A simulation study was carried out to investigate the temporal evolution of H2S in the Huangcaoxia underground gas storage (UGS), which is converted from a depleted sulfur-containing gas field. Based on the rock and fluid properties of the Huangcaoxia gas field, a multilayered model was built. The upper layer Jia-2 contains a high concentration of H2S (27.2 g/m3), and the lower layer Jia-1 contains a low concentration of H2S (14.0 mg/m3). There is also a low-permeability interlayer between Jia-1 and Jia-2. The multi-component fluid characterizations for Jia-1 and Jia-2 were implemented separately using the Peng-Robinson equation of state in order to perform the compositional simulation. The H2S concentration gradually increased in a single cycle and peaked at the end of the production season. The peak H2S concentration in each cycle showed a decreasing trend when the recovery factor (RF) of the gas field was lower than 70%. When the RF was above 70%, the peak H2S concentration increased first and then decreased. A higher reservoir RF, a higher maximum working pressure, and a higher working gas ratio will lead to a higher H2S removal efficiency. Similar to developing multi-layered petroleum fields, the operation of multilayered gas storage can also be divided into multi-layer commingled operation and independent operation for different layers. When the two layers are combined to build the storage, the sweet gas produced from Jia-1 can spontaneously mix with the sour gas produced from Jia-2 within the wellbore, which can significantly reduce the overall H2S concentration in the wellstream. When the working gas volume is set constant, the allocation ratio between the two layers has little effect on the H2S removal. After nine cycles, the produced gas’s H2S concentration can be lowered to 20 mg/m3. Our study recommends combining the Jia-2 and Jia-1 layers to build the Huangcaoxia underground gas storage. This plan can quickly reduce the H2S concentration of the produced gas to 20 mg/m3, thus meeting the gas export standards as well as the HSE (Health, Safety, and Environment) requirements in the field. This study helps the engineers understand the H2S removal for sulfur-containing UGS as well as provides technical guidelines for converting other multilayered sour gas fields into underground storage sites.

Molecular insights into the synergistic mechanisms of hybrid CO2-surfactant thermal systems at heavy oil-water interfaces

A hybrid thermal recovery process is a promising EOR (Enhanced Oil Recovery) method and has been widely applied to post-steamed heavy oil reservoirs. Due to the complexity of High Temperature and High Pressure (HTHP) reservoir environments, Molecules Dynamics (MD) simulations are conducted to investigate the interfacial behavior between multiphase multicomponent fluids and heavy oil over a wide temperature range. We select CO2 and a cost-effective anionic surfactant, SDS (Sodium Dodecyl Sulfate), to build hybrid thermal systems. The interfacial behavior in different systems is characterized by the local density distribution, cluster analysis, hydrogen bond characters, solvent accessible surface area, and interaction energy. Systematic MD simulations reveal a two-step interfacial tension (IFT) reduction process stimulated by thermal migration. Both CO2 and SDS can achieve an IFT decrement with different mechanisms. Moreover, a co-addition of CO2 and SDS can further efficiently reduce the IFT. Average Reduced Density Gradient (aRDG) results reveal that a unique asphaltenes-SDS-CO2 structure improves the interfacial activities and mobility of the heavy oil phase through a bidirectional mass exchange mechanism, which ultimately realizes the most significant IFT decrement. Furthermore, an optimal concentration (10C–20S) in a hybrid thermal system is recommended because of its balanced performance. This work sheds insight into the synergistic effects of multiphase multicomponent thermal fluids on hybrid thermal systems, which will guide future field applications of hybrid thermal EOR processes.

NUMERICAL SIMULATION OF PROCESS FLUID FLOW IN THE PIPES OF A COILED TUBING INSTALLATION

Today, one of the modern trends is the use of coiled tubing technologies and improvement of the composition of washing agents (liquids). The features of coiled tubing technological sections are considered – spiral pipe laying, the ratio of the main dimensions of flexible pipes, drum and guide sector. The presence of a pipe conveyor gives special responsibility for ensuring the movement of a string of flexible pipes within a given load range. The length of the pipes reaches 5000 m. The radial dimensions of the well are 150 mm. The stages of determining the main parameters of a pumping unit for supplying process fluid to a well are listed. When carrying out technological operations, the pump must overcome the hydrodynamic losses of direct and reverse fluid supply into the well. It is necessary to take into account the possibility of misalignment of cylindrical pipes. To carry out technological operations to intensify oil production, multicomponent process fluids are used. The presence of chemical and polymer additives in liquids has a significant impact on the properties of aqueous and hydrocarbon systems and forms gels of varying density, viscosity and rheology. It is known that even a small content of polymer additives in the solution (6–30 g/l) leads to non-Newtonian behavior of the washing fluid in the well pipes. The work uses experimental data obtained by Region LLC of Ukraine. For numerical modeling of the hydrodynamic characteristics of a process fluid, linear and nonlinear models of a viscous fluid are used. In all cases, steady flow was considered. Due to the fact that the work uses the academic version of the ANSYS CFD package with limited capabilities in terms of the number of cells, the computational areas were selected using simplified schemes. The following schemes are considered: spiral – guide – straight pipe, only the spiral part of winding the pipe on a drum, an annular space between cylindrical pipes with possible eccentricity. The results of numerous studies are used to predict hydraulic resistance coefficients in pipes and the characteristics of pumping equipment for supplying process fluid to a well. The results can also be used for verification strength calculations of flexible pipe columns for hazardous sections.

Simulation of Multi-component Thermal Fluid Flooding in Horizontal Well of Offshore Heavy Oil Reservoirs

After many-turns of huff and puff of multi-component thermal fluid, only the heavy oil in a limited area near the wellbore is produced. However, the inter-well areas, namely the dead oil areas, are not influenced by multi-component thermal fluid. Therefore, it is necessary to carry out the research on multi-component thermal fluid flooding. The facility of thermal recovery 3D physical stimulation is adopted to carry out simulation of flooding in various well spacing of pseudo-line well pattern, and producer-injector spacing and parameters are optimized with numerical simulation. The results of physical simulation and numerical simulation results show that the effect of the 250m spacing of well pattern with injectior-productor ratio 1:3 is better than other well spacing, with maximum recovery of 56.02%. The research results provide a technical support for the offshore multi-component thermal fluid flooding experiment.