Atomistic Modeling and Simulation for Solving Gas Extraction Problems
Proof-of-concept results are presented on the application of molecular modeling and simulation to the gas extraction problems. Both hydrocarbon mixtures and gas hydrates in porous media are considered.
This book is a collection of select proceedings of the FOMMS 2015 conference. FOMMS 2015 was the sixth triennial FOMMS conference showcasing applications of theory of computational quantum chemistry, molecular science, and engineering simulation. The theme of the 2015 meeting was on Molecular Modeling and the Materials Genome. This volume comprises chapters on many distinct applications of molecular modeling techniques. The content will be useful to researchers and students alike.
iffusion is one of the key subjects of molecular modeling and simulation studies. However, there is an unresolved lack of consistency between Einstein-Smoluchowski (E-S) and Green-Kubo (G-K) methods for diffusion coefficient calculations in systems of complex molecules. In this paper, we analyze this problem for the case of liquid n-triacontane. The non-conventional long-time tails of the velocity autocorrelation function (VACF) are found for this system. Temperature dependence of the VACF tail decay exponent is defined. The proper inclusion of the long-time tail contributions to the diffusion coefficient calculation results in the consistency between G-K and E-S methods. Having considered the major factors influencing the precision of the diffusion rate calculations in comparison with experimental data (system size effects and force field parameters), we point to hydrogen nuclear quantum effects as, presumably, the last obstacle to fully consistent n-alkane description.
Molecular modelling is used to calculate transport properties and to study relaxation of liquid n-triacontane (C30H62). The problem is important in connection with the behavior of liquid isolators in a pre-breakdown state. Two all-atom models and a united-atom model are used. Shear viscosity is calculated using the Green–Kubo formula. The force fields are compared with each other using the following criteria: the required time for one molecular dynamics step, the compliance of the main physical and transport properties with experimental values. The problem of the system equilibration is considered. The united-atom potential is used to model the n-triacontane liquid with an initial directional orientation. The time of relaxation to the disordered state, when all molecules orientations are randomized, are obtained. The influence of the molecules orientations on the shear viscosity value and the shear viscosity relaxation are treated.
In the XXI century the Arctic region is a matter of huge interest of many parties, including not only countries, but also large companies and international organisations. Fragile environment, influence of climate change, technological progress, rich resource base and unresolved border
disputes guarantee attention to the territory. However, even considering those variables, we believe that system analysis is more relevant, giving an opportunity to see the whole picture instead of fragments and local issues. The main question posed in this work is how to find balance between common and specific, general and individual in the Arctic, and the authors believe they succeeded in solving this problem. We believe that understanding of the Arctic is only possible when taking into consideration its history, geography, environment, legal issues and economic prospects. In other words, the only approach possible needs to cover all the regional issues and analyze these important factors, which is provided by the new institutional economics, through the union of fundamental and applied science.
The comparison methodology for the use of integrated indicators of economic efficiency of projects for the development of hydrocarbon reserves in the formation of the resource base in a planned and a market economy in Russia. Case studies expert decision-making showed that economic sections of existing regulations in the field of subsurface hydrocarbons need to be revised. The universal criterion of economic justification of rational variants of development of hydrocarbon reserves as the development of facilities, and on the field as a whole, which provides consensus interests of the state and subsoil user. Project performance indicators provides a clear economic characteristics of such concepts as "selective development" and " hard to recover reserves"