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181.
The objective of this paper is to present an overview of the fundamental equations governing transport phenomena in compressible reservoirs. A general mathematical model is presented for important thermo-mechanical processes operative in a reservoir. Such a formulation includes equations governing multiphase fluid (gas-water-hydrocarbon) flow, energy transport, and reservoir skeleton deformation. The model allows phase changes due to gas solubility. Furthermore, Terzaghi's concept of effective stress and stress-strain relations are incorporated into the general model. The functional relations among various model parameters which cause the nonlinearity of the system of equations are explained within the context of reservoir engineering principles. Simplified equations and appropriate boundary conditions have also been presented for various cases. It has been demonstrated that various well-known equations such as Jacob, Terzaghi, Buckley-Leverett, Richards, solute transport, black-oil, and Biot equations are simplifications of the compositional model.Notation List
B
reservoir thickness
- B
formation volume factor of phase
- Ci
mass of component i dissolved per total volume of solution
- C
i
mass fraction of component i in phase
- C
heat capacity of phase at constant volume
- Cp
heat capacity of phase at constant pressure
- D
i
hydrodynamic dispersion coefficient of component i in phase
- DMTf
thermal liquid diffusivity for fluid f
-
F
= F(x, y, z, t) defines the boundary surface
- fp
fractional flow of phase
-
g
gravitational acceleration
- Hp
enthalpy per unit mass of phase
- Jp
volumetric flux of phase
- krf
relative permeability to fluid f
- k0
absolute permeability of the medium
- Mp
i
mass of component i in phase
-
n
porosity
-
N
rate of accretion
- Pf
pressure in fluid f
- pca
capillary pressure between phases and =p-p
- Ri
rate of mass transfer of component i from phase to phase
- Ri
source
source rate of component i within phase
- S
saturation of phase
-
s
gas solubility
-
T
temperature
-
t
time
-
U
displacement vector
-
u
velocity in the x-direction
-
v
velocity in the y-direction
- V
volume of phase
- Vs
velocity of soil solids
- Wi
body force in coordinate direction i
-
x
horizontal coordinate
-
z
vertical coordinate
Greek Letters p
volumetric coefficient of compressibility
- T
volumetric coefficient of thermal expansion
- ij
Kronecker delta
-
volumetric strain
- m
thermal conductivity of the whole matrix
-
internal energy per unit mass of phase
-
gf
suction head
-
density of phase
- ij
tensor of total stresses
- ij
tensor of effective stresses
-
volumetric content of phase
- f
viscosity of fluid f 相似文献
182.
Yavuz Ugurlu 《Physics letters. A》2008,372(16):2867-2873
In this Letter, we consider a system of generalized Drinfeld-Sokolov (gDS) equations which models one-dimensional nonlinear wave processes in two-component media. We find some exact solutions of gDS by using tanh function method and we also obtain a numerical solution by using the Adomian's Decomposition Method (ADM). 相似文献
183.
Safacan Kolemen Yusuf Cakmak Tugba Ozdemir Sule Erten-Ela Muhammed Buyuktemiz Yavuz Dede Engin U. Akkaya 《Tetrahedron》2014
Two electron rich Bodipy dyes with strong absorptivities in the visible region were designed and synthesized as potential electron donors in bulk heterojunction photovoltaic constructs. Overall efficiency is above 1%, with impressive responsiveness at both UV and near-IR ends of the visible spectrum. Computational studies reveal an unexpected effect of meso-substituents on the electron transfer efficiency. 相似文献
184.
Aura Ganz Yavuz Varoglu 《Fiber and Integrated Optics》1995,14(1):15-36
In this paper we present time-wavelength assignment algorithms that consider the following system parameters: (1) the system hardware in terms of the transmitters' and receivers' tuning capabilities (slow or fast tuning) and (2) the traffic matrix. The ulgorithms' objective is to maximize the bandwidth efficiency, i.e., to minimize the frame duration. Each algorithm will be suitable for a different set of system parameters. We present trade-offs between the system hardware and the algorithm' performance for various traffic patterns. These trade-offs can be used as guidelines for the system designer that needs to decide the system hardware for a given traffic pattern and required system performance. Moreouer, for a given system hardware and traffic patterns, each node can distributively decide which algorithm should be used, i.e., the algorithm that will maximize the system performance. 相似文献
185.
Background correction by wavelength modulation using a microcomputer in atomic emission spectrometry
Ali Gökmen Mehrdad Delzendeh Mürvet Volkan O. Yavuz Ataman John M. Ottaway 《Mikrochimica acta》1986,89(1-6):357-367
An Apple IIe microcomputer was employed to correct the background radiation in electrothermal atomization atomic emission spectrometry (ETA-AES). In ETA-AES, black-body radiation from the atomizer as well as any broadband molecular emission should be corrected to obtain an atomic signal alone. A quartz plate run by a G325D galvanometric motor was placed before the exit slit of a 256 mm Littrow monochromator. Improvements by a novel pulsed 3-step square waveform are demonstrated compared with the ordinatry 3-step square waveform. A soft delay was also applied in order to avoid taking data at transition stages of the quartz plate. A line and a continuum source are used to simulate offsetting of the DC component of the signal prior to the ADC. This provides a better utilization of the full dynamic range of the converter. 相似文献
186.
S. Altin M.A. Aksan S. Turkoglu M.E. Yakinci 《Physica C: Superconductivity and its Applications》2011,471(23-24):1692-1698
NdCeCuO superconducting samples were fabricated using ethyl alcohol, acetone and ethylenediaminetetraacetic acid (EDTA) as binding agents. For evaporation of binding agents, the samples were heat treated at 1050 °C for 24 h and then at 950 °C for 6–48 h under argon atmosphere to obtain the superconducting phase. The best superconducting performance was found in the sample heat treated at 1050 °C for 24 h and then 950 °C for 12 h which was fabricated by using acetone as binding agent. The Tc and T0 value was found to be ~25 K and 23.4 K, respectively. Grain size in the samples fabricated was calculated using Scherer equation and SEM data. It was found that grain size strongly depends on the binding agents and heat treatment conditions. Some cracks and voids on the surface of the samples were observed, which influences the superconducting and electrical transport properties of the samples. 相似文献
187.
Herein we demonstrated the preparation of 3,4-ethylenedioxythiophene (EDOT) containing polynorbornylene brushes on Au surfaces via surface-initiated ring-opening metathesis polymerization (SI-ROMP). Using solid-state oxidative crosslinking technique, these polymer brushes were electrochemically converted to conjugated polymer networks. Grazing-angle FTIR spectra of polymer brushes clearly showed the characteristic vibrations of EDOT and norbornylene groups. Furthermore, densely covered Au substrates with polynorbornylene brushes were characterized by using scanning electron microscopy and atomic force microscopy. 相似文献
188.
In this study, composition of essential oil and antioxidant capacity of Centaurea drabifolia subsp. detonsa were investigated. The antioxidant capacity of the methanolic extract was evaluated by various methods including measuring the total phenolic content, total antioxidant capacity, free radical scavenging activity (DPPH assay), β-carotene/linoleic acid bleaching assay and ferric and cupric ion reducing power assay. The composition of essential oil was identified by using gas chromatography-mass spectrometry. Totally, 41 compounds were described in the essential oil. Germacrene D (44.829%) was determined as the major compound of the essential oil. The total phenolic content, total antioxidant capacity, inhibition rate of oxidation of linoleic acid, IC(50) (in DPPH assay) and EC(50) (in reducing power) value were found to be 40.454?mg?GAE/g, 100.840?mg?AAE/g, 65.639%, 39.584?μg?mL(-1) and 0.603?mg?mL(-1), respectively. The results indicated that the extract of C. drabifolia subsp. detonsa has strong antioxidant properties and this species can be used as a natural antioxidant in food processing and pharmaceutical industries. 相似文献
189.
Atomic carbon, a reactive intermediate abundant in the interstellar medium (ISM) can participate in various energetically demanding reactions in its extremely long living (69 min) first excited singlet state ((1)D). Several studies on reactions of oxygen containing species with carbon atoms have been reported, however mechanistic details of the title reaction remain obscure. We report here quantum chemical studies on reactions of methanol with (3)P and (1)D carbon atoms at the CCSD(T)/cc-pVTZ level of theory, with which experimentally well known facile CO production, intermolecular acetaldehyde formation, and intermolecular dimethoxymethane production mechanisms are explained. Energetics of the fragmentation, O-H insertion, C-H insertion, and O-C insertion channels on the triplet and singlet surfaces are studied. The CO production mechanism by C ((1)D) is identified as an oxygen abstraction and a triplet PES seems non-operative. Presenting novel features for the intermolecular reaction channels, current findings may be applicable to C + ROR reactions. 相似文献
190.
İlyas Yavuz 《International Journal of Mathematical Education in Science & Technology》2013,44(4):467-485
This study examines how students in the early stages of learning about the concept of functions, describe a curve and, in particular, evaluate the appropriateness of their argument about the representation of a function. Students are offered a message game which is related to a curve drawn on a coordinate system, representing an ‘imaginary function’. In this message game, one half of the class must describe a curve to the other half who will then try to reproduce it as similarly as possible. Data analysis indicates that the idea of the curve that consists of series of points is very effective, while the idea of variation does not exist or is too limited among students at the beginning of learning functions. Thus, the concept of variation is not used as a criterion to describe a curve. More surprisingly, the students are working on the curve as if it was just a picture on a grid regardless of the representation of the function. 相似文献