Chages in parameters of deposits No. 301, 302, 303 of Romashkinskoye oil field in modeling reservoir conditions

Parameters of the carbonate rocks of the oil deposits of 301, 302 and 303 of Romashkinskoye field were estimated on 69 core samples. Modelling of reservoir conditions during deposits development was carried out using IFES-1 facility (Republic of Bashkortostan, Oktyabrsky, VNIIGIS). We estimated true resistivity, P-wave velocity and the porosity before loading the sample and after load removal. Samples were placed in a chamber and the measurements were made under conditions close to the reservoir ones. Loading configuration intended constant confining pressure (rock pressure) and changes in pore (reservoir) pressure. At each stage of reservoir pressure changing it has been given a certain period (30 min) to complete the transition process. Two months after the measurement (after full restoration of elasto-mechanical properties) we determined gas permeability of samples again. Porosity of Vereckiann rocks was 3-20 %, of Bashkirian - 1.5-21 %, of Protvinskian - 0.2-23 %. We considered two variants of the technology-related loading: soft and hard. In the soft mode pore (reservoir) pressure reduced from maximum (6.56-7.15 MPa) to an average value (2.24-4.0 MPa) and then restore to maximum. In the hard mode pressure reduced from maximum pore (reservoir) pressure to average value, decreased to minimum (1.0-0.2 MPa) and then restored to maximum. We determined that rocks parameters had not significantly changed under soft mode of technology-related loading. Under hard mode of loading porosity decreased, true resistivity and P-wave velocity grew up. Comparative analysis shows that for the majority of collector of the Vereiskian and Bashkirian productive horizons gas permeability is characterized by reduction of porosity. In case of Protvinskian high fractured rocks gas permeability increases sometimes

Comparative analysis of algorithm for solving teaching objectives in four language environments

© Research India Publications. In this article, we present the results of comparative analysis of five popular programming languages – three of which are compilable ones(C#, C++, Pascal) and two interpreted languages (Java and Python). Analysis has been performed in the base of comparison of implementation of various algorithms for solving of classical tasks from the discipline called “Computer technology and programming”, as well as the discipline “Programming languages”. Tasks for finding GCD (greatest common divisor) were used, as well as sorting of integral values’ array, search in ordered array of integral values, and substring searching in the string. In addition, we provided indices of read rate and record rate, exemplified by reading array of integers from text fine, as well as recoding array of integers into text file. Comparison has been made according to the following three criteria: finite code length, weigh of executable file, program execution time at various tests. For illustrative purposes, obtained results are shown in diagrams with clarifications and summary results

Interaction of the acoustic signal with motionless discretely layered medium containing a layer of bubbly liquid

© 2017, Pleiades Publishing, Ltd.The dynamics of the pulse perturbation of the low-amplitude pressure in the motionless discretely layered medium containing a layer of liquid with polydisperse gas bubbles has been studied theoretically. Theoretical method basics of the calculation of the acoustic signal distortion during the diagnostics of multilayer samples containing a layer of bubbly liquid are presented. It is shown that specific dispersion and dissipative properties of the layer of bubbly liquid can affect considerably the dynamics of the acoustic signal in the multilayer medium as a function of the main frequency of the signal. The theoretical models of the dynamics of multiphase media can be verified using this method. It was established that it is possible to use this theory for the calculation of the acoustic signal distortion at its interaction with multilayer objects containing the layer of bubbly liquid

Propagation of acoustic waves in liquid containing multilayer barrier

© Published under licence by IOP Publishing Ltd. The dynamics of acoustic waves in a liquid containing multilayer barrier is studied. Using the subroutine of the fast Fourier transform the calculation of the distortion of the acoustic signal at the diagnosis of a multilayer sample comprising a layer of a liquid with polydispersed bubbles is executed. A good agreement between theoretical and experimental data is obtained

CALCULATION OF ELASTOVISCOPLASTIC DISPLACEMENT OF WELL WALLS IN TRANSVERSAL AND ISOTROPIC ROCKS

The relevance of the work is justified by the need to improve the technical and economic indicators of well construction based on forecasting and preventing drilling tools sticking due to the narrowing of an open well bore in the intervals of transversely isotropic rocks. A mathematical model of elastic-viscous-plastic displacement of the walls of inclined and horizontal wells has been developed during the narrowing of the open borehole due to rock creep in the intervals of transversely isotropic rocks. In the program developed based on this mathematical model, the calculation of the elastic-viscous-plastic displacement of the walls of an obliquely directed and horizontal well in the reservoir of argillite from the Western Siberia deposit was carried out. As a result of the calculation, it was established that after opening the rock with bits, the cross-section of the open borehole due to the rock creep eventually takes the form of an ellipse, the small axis of which is in the plane of the upper wall of the well and decreases with time

Condensation of 4-hydroxy-2-thiazolines with 1,2-phenylenediamine as a novel effective route to thiazolo[3,4-a]quinoxalines

Thiazolo[3,4-a]quinoxalin-4-ones were prepared in two steps starting from methyl phenylchloropyruvate using a new strategy for the construction of the ring system. A key step in this new method involves the reaction of 4-hydroxytetrahydrothiazoles with 1,2-phenylendiamines

Directional diagrams of the particle drift in a standing wave with account of the basset force

© 2015 Springer Science+Business Media New York. A study is made of the threshold parametric values at which the direction of the particle drift in a standing wave is reversed, with account taken of the Basset force at different Reynolds and Strouhal numbers. The dependences of the threshold value squared of the entrainment coefficient on the relative density of the particle with account and without account of the Basset force are found. The influence of the Basset force on the threshold value of the density parameter is investigated. It is shown that account taken of the Basset force exerts a particularly strong influence on the threshold curves for nondense particles. The threshold values of density of the particle and of the coefficient of its entrainment decrease as the Strouhal number increases

Impact of Basset force on threshold values of particle drag coefficient and density parameter in standing sinusoidal wave

© Published under licence by IOP Publishing Ltd. A one-dimensional drift of spherical particle in standing sinusoidal wave is studied numerically. The impact of stationary and non-stationary forces of viscous drag, as well as Archimedes, added masses and Basset forces on particle drift direction is investigated. For various Reynolds and Strouhal numbers the dependencies of the threshold particle drag coefficient on density parameter have been found. These dependencies show that with increasing Reynolds and Strouhal numbers the threshold value of the squared drag coefficient decreases markedly. Impact of Basset force on threshold values is especially strong for low- density particles