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In this paper, the flow of multiphase fluids in a one-dimensional homogeneous porous media involving the gravity effects is numerically studied using the dominant wave method. The paper aims to discuss these issues.

The numerical scheme used for solving the pressure equations, obtained for the black-oil model, is a backward Euler scheme while the hyperbolic mass conservation equations, derived for both black-oil and Buckley-Leverett models, are solved using the dominant wave method. Higher-order schemes are achieved using either variable derivatives along with the minmod limiter or a MUSCL type interface construction scheme using the Fromm's limiter. The mass conservation equations are solved using the first-order forward Euler method in time. Harten's entropy correction procedure is employed to avoid non-physical expansion shocks.

It was found that the dominant wave method can accurately solve multiphase flow equations involving gravity effects. Numerical experiments also show that both minmod and Fromm's limiters can be successfully used to construct higher-order schemes while the minmod limiter gives slightly more diffuse solutions.

The flow models considered here include two- and three-phase Buckley-Leverett and the black-oil models and the capillary effects are neglected.

The proposed scheme can be efficiently used for solving problems involving non-convex flux functions especially those experienced during gravity drainage process in hydrocarbon reservoirs.

To the best of authors knowledge, this is the first time that the dominant wave method has been used to tackle multiphase flow problems involving gravity effect.

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.

The high viscosity of heavy oil is a serious problem for the recovery efficiency of this resource by conventional methods. Since a few past years, the vapour extraction process (VAPEX) has emerged as a promising technology for the recovery of heavy oils and bitumen in reservoirs where thermal methods, such as steam-assisted gravity drainage cannot be applied. Recently, the use of CO₂ as a solvent is believed to make the VAPEX process more economical and environmentally and technically attractive. Convective mixing at the edge of the solvent chamber enhances mass and heat transfer rates which increases oil mobility and production rate. The objective of this study is to analysis the influence of the main controlling parameters, such as buoyancy ratio and Prandtl number on the flow patterns and mass transfer mechanism, in order to understand the thermal effect on the dissolution of carbon dioxide through natural convection at the boundary layer of solvent chamber of CO₂-VAPEX process. The numerical results obtained by lattice Boltzmann method show that the flow structure and the mass transfer mechanism are strongly depend on the buoyancy ratio and Prandtl number. So, the performances of CO₂-VAPEX process are strongly influenced by thermal effect; and we found that it has negative consequences on this process.

Bangladesh is one of the most disaster‐prone countries in the world. Natural disasters adversely affect the country's economy and deter its development. Thus preparedness for the disasters, along with effective prevention and mitigation measures, is imperative for sustainable development of the country. The purpose of this paper is to examine the present state of disaster preparedness in the country with special attention to the more frequent and damaging disasters – flood and cyclone.

A detailed study of the effects of natural disasters, disaster prevention and mitigation measures, and institutional setting for disaster preparedness was undertaken.

Plans and programs have been formulated to manage natural disasters. In a “Cyclone Preparedness Program”, trained volunteers facilitate emergency response and proper use of the multi‐purpose shelters. Within an institutional framework for disaster management, several Non‐Government Organizations (NGOs) work for disaster preparedness alongside the government organizations. Their formal and nonformal education programs on disaster preparedness have a common objective of promoting resilient and sustainable communities.

Planning and design of structural interventions for prevention and mitigation of natural disasters should be done more carefully to avoid adverse impacts on the environment. A participatory approach is essential in this process. Education and awareness‐building programs need wider and easier access to the people.

The paper concludes that the institutional arrangement for cyclone preparedness and response is unique and efficient, and that participation of NGOs in the preparedness program contributes significantly toward sustainable development. These lessons will be important for development planning in other sectors.

Reviews the contribution to “rapid tooling” of QuickCast 1.0 and QuickCast 1.1. Explains the genesis and development of QuickCast 1.0, illustrating both its technical ability, and its capacity for saving time and money, and also outlining its industrial shortcomings. Gives a thorough elucidation to the more recently introduced QuickCast 1.1 at both theoretical and practical levels – its range of potential applications being documented through case studies – and presents it in terms of its capacity to solve those problems that its predecessor could not. Discusses in detail the characteristics of solutions to these problem areas and provides test results obtained at various foundries.