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The two‐dimensional flow field is numerically investigated using a compact finite difference and a pseudo‐spectral method when two fluids with different physical properties are mixing under gravity as well as flow rate. The gravity and the viscous mobility affect the fingering instability, i.e. the mixing range shrinks much at the large viscous mobility or the strong gravity. When the gravitation acts parallel to the main stream, the flow decelerates or accelerates according to its direction. The fingertip velocity is exactly expressed by a pure cosine function and especially invariant when the gravity acts along the −y direction at the high Peclet number. The maximum and fingertip velocities at the very low Peclet number are nearly symmetric with respect to the −y direction perpendicular to the main flow direction x. When the gravity acts along the −y direction, the flow field shows the asymmetry, and a pair of vortices is generated at both the very high Peclet number and less viscous mobility number. As the viscous mobility becomes large, the vortex scale enlarges at the small Peclet number, while the vortices are slightly destroyed at the relatively high Peclet number. As the gravitational angle changes clockwise from downstream to upstream, a pair of vortices evolves through a process of asymmetry.

Miscible displacement of a more viscous finite layer in porous media is simulated by means of high accuracy numerical schemes. Viscous fingers on the trailing front where the mobility ratio is unfavorable are found to catch up, however they never break through the stable leading front. Two stages of fingering orientation are observed. At an earlier time when the influences of finite thickness of the layer are not yet fully realized, the fingers move forward with the similar features to the conventional fingering findings. However, these fingering patterns are redirected upstream after the arrival of most of fingers to the leading front. The leading front remains stable with strong dispersion effects and moves nearly constantly with original displacing velocity. The growth rate of the layer thickness depends strongly on the viscosity ratio.

Non‐Newtonian fluids are used in current oil recovery processes. These fluids do not satisfy the linear Darcy law for flow through porous media. To model the recovery processes, a generalization of Darcy's law is used. A numerical method, developed originally for salt and fresh groundwater flow, has been adapted to incorporate the generalized Darcy law. We use it to model the two‐phase, two‐dimensional flow of immiscible fluids in a porous medium. In particular it will be applied to investigate the stability of the fluid/fluid interface. The results verify the theoretically predicted critical velocity above which the displacement of oil by polymer flooding becomes unstable, leading to low recovery.

Displacements of a miscible magnetic layer in a capillary tube under a moving ring‐shaped magnet are studied numerically. The magnet is adjusted dynamically to maintain a constant distance from the front mixing interface on the centerline. Control parameters, such as magnetic strength, effective viscosity variation due to magnetization, diffusion and the position of the magnet, are analyzed systematically. Motion of the magnetic layer is evaluated by two quantitative measurements, i.e. movement of center of gravity and spread of layer width. In general, the moving speed of the center of gravity depends only slightly on the magnetic strength, and is found slower at a higher viscosity ratio and a closer placement to the front interface as well if the magnet is placed amid the layer. A weaker spread occurs in situations of stronger magnetic strength, lower viscosity parameters and also placements near the rear interface. A multi‐front finger results if the magnet is positioned ahead of the front interface.

The aim of this study is to numerically simulate the density-driven convection in heterogeneous porous media associated with anisotropic permeability field, which is important to the safe and stable long term CO₂ storage in laminar saline aquifers.

The study uses compact finite difference and the pseudospectral method to solve Darcy’s law.

The presence of heterogeneous anisotropy may result in non-monotonic trend of the breakthrough time and quantity of CO₂ dissolved in the porous medium, which are important to the CO₂ underground storage.

The manuscript numerically study the convective phenomena of mixture contained CO₂ and brine. The phenomena are important to the process of CO₂ enhanced oil recovery. Interesting qualitative patterns and quantitative trends are revealed in the manuscript.

During the past 50 years the phenomenon of nuclear magnetic resonance (NMR) has evolved from a scientific curiosity to a powerful analytical tool for physical scientists and the medical community. Its primary use is for analytical chemistry and medical imaging. NMR imaging and spectroscopy can non‐invasively and non‐destructively examine the physical and chemical composition of materials. The technology is now at a level of sophistication and maturity where industrial applications are possible. This article describes the basis of NMR imaging and spectroscopy and examines the application of NMR to a broad range of industrial applications.

Because of the increasing global oil demand, efforts have been made to further extract oil using chemical enhanced oil recovery (CEOR) methods. However, unlike water flooding, understanding the physicochemical properties of crude oil and its sandstone reservoir makeup is the first step before embarking to CEOR projects. These properties play major roles in the area of EOR technologies and are important for the development of reliable chemical flooding agents; also, they are key parameters used to evaluate the economic and technical feasibilities of production and refining processes in the oil industries. Consequently, this paper aims to investigate various important physicochemical properties of crude oil (specific gravity; American Petroleum Institute [API]; viscosity; pour point; basic sediment and water; wax; and saturate, aromatic, resins and asphaltenes components) and sandstone reservoir makeup (porosity, permeability, bulk volume and density, grain volume and density, morphology and mineral composition and distributions) obtained from Malaysian oil field (MOF) for oil recovery prediction and design of promising chemical flooding agents.

Three reservoir sandstones from different depths (CORE 1; 5601, CORE 2; 6173 and CORE 3; 6182 ft) as well as its crude oil were obtained from the MOF, and various characterization instruments, such as high temperature gas chromatography and column chromatography for crude’s fractions identification; GC-simulated distillation for boiling point distribution; POROPERM for porosity and permeability; CT-Scan and scanning electron microscopy-energy dispersive X-ray for morphology and mineral distribution; wax instrument (wax content); pour point analyser (pour point); and visco-rheometre (viscosity), were used for the characterizations.

Experimental data gathered from this study show that the field contains low viscous (0.0018-0.014 Pa.s) sweet and light-typed crude because of low sulfur content (0.03 per cent), API gravity (43.1o), high proportion of volatile components (51.78 per cent) and insignificant traces of heavy components (0.02 per cent). Similarly, the rock permeability trend with depth was found in the order of CORE 1 < CORE 2 < CORE 3, and other parameters such as pore volume (Vp), bulk volume (Vb) and grain volume (Vg) also decrease in general. For grain density, the variation is small and insignificant, but for bulk density, CORE 2 records lower than CORE 3 by more than 1 per cent. In the mineral composition analysis, the CORE 2 contains the highest identified mineral content, with the exception of quarts where it was higher in the CORE 3. Thus, a good flow crude characteristic, permeability trend and the net mineral concentrations identified in this reservoir would not affect the economic viability of the CEOR method and predicts the validation of the MOF as a potential field that could respond to CEOR method successfully.

This paper is the first of its kind to combine the two important oil field properties to scientifically predict the evaluation of an oil field (MOF) as a step forward toward development of novel chemical flooding agents for application in EOR. Hence, information obtained from this paper would help in the development of reliable chemical flooding agents and designing of EOR methods.

This paper aims to investigate the use of a piezo fan in an enclosure on wall heat transfer and thermal boundary layer profile in constant wall temperature situation.

The governing partial differential equations of mass, momentum and energy in addition to boundary conditions are solved by lattice Boltzmann method. The problem is solved numerically using D2Q9 population's model and Bhatnagar–Gross–Krook collision model with a code written in MATLAB.

The effects of Prandtl number (Pr) and the frequency of piezo fan vibrations are critically investigated on the hydrothermal characteristics of the square cavity. The mesh independency study and the validation of the proposed model are accomplished with numerical results of Ghia et al. (1982) and analytical solution of pure conduction very good agreement is found between present results and benchmark findings. Generally, with increasing beam frequency, the heat removal from heat source increased. It is found that, for all Prandtl numbers, wall Nusselt number will increase with the increase of the beam frequency. This enhancement is more intense in higher Prandtl number.

Based on these results, the use of piezo fan in an enclosure can be classified as standalone as well as heat sink integrated cooling solution.

In this work, it is presented a locally conservative multiscale algorithm accounting the mineralization process during the supercritical carbon dioxide injection into a deep saline aquifer. The purpose of this study is to address numerically the geological storage of CO₂ in a highly heterogeneous reservoir, leading with interactions among several phenomena in multiple scales.

This algorithm have features that distinguish it from the presently available solvers which are: (i) an appropriate combination of a coupled transport system solver using a high-order non-oscillatory central-scheme finite volume method and, elliptic numerical approach applying a locally conservative finite element method for Darcy’s law and, (ii) the capability of leading with interactions among several phenomena in multiple scales.

As a result, this approach was able to quantify the precipitation of the carbonate crystals at the solid interface.

Application of foam in enhanced oil recovery requires a production of foam that is strong and stable enough to withstand a long period. There are numerous factors that may affect the performance of foam, among which is temperature. Therefore, this study aims to observe the foam performance at different temperature by evaluating the foamability and the stability of the foam.

In this study, bulk foam test using FoamScan was conducted to examine the effect of temperature on foam in the presence of crude oil. Nitrogen gas was sparged through the mixture of crude oil, an in-house developed surfactant, and sodium chloride solution as the brine at different temperatures to produce foam at a certain height. The crude oil was extracted from an oilfield in East Malaysia and the in-house developed surfactant was a mixture of amphoteric and anionic surfactants. A camera continuously recorded the height of foam during the generation and the collapse of the foam. The foamability and foam stability properties of each sample were taken as the indicators for foam performance. Furthermore, the entering, spreading and bridging analysis was run to observe the effect of the presence of crude oil on foam performance.

In general, the higher the temperature, the less stable the foam is. As the stability of foam is associated with the rate of liquid drainage, it was observed that as temperature increases, the rate of liquid drainage also increases. On the other hand, the entering, spreading and bridging analysis shows that there is entering of oil droplet happening on the interface of foam film that may promote the rupture of the foam film even more.

It was found that the temperature has a small impact on foamability, whereas the foam stability was significantly affected by the temperature. Therefore, it can be concluded that foamability is not necessarily interrelated to foam stability, contradicting to the findings of few authors.