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1.
The concepts of subcritical and supercritical flows are introduced for the long-wave approximation model describing stationary
free-boundary rotational flows of an ideal incompressible fluid. Shear flows of a fluid layer above an uneven bottom are analyzed.
Exact solutions describing different flow regimes are constructed, and the flow properties are studied as a function of the
flow regime. Flows with backward streamlines are considered.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 4, pp. 26–38, July–August, 2006.
An erratum to this article is available at . 相似文献
2.
V. A. Batishchev 《Journal of Applied Mechanics and Technical Physics》1999,40(3):479-484
Thermocapillary flows of a fluid in a lamina with a rigid lower wall and a free upper surface, along which the temperature
gradient is given in the radial direction, are investigated for large Marangoni numbers. Self-similar solutions which describe
the axisymmetric flow regimes of a fluid without the circumferential velocity component are constructed numerically and asymptotically
for a system of Prandtl equations. It is shown that a pair of new self-similar flow regimes of a fluid with rotation branches
off from the regimes obtained. The new regimes ere calculated numerically and asymptotically.
Rostov State University, Rostov-on-Don 344090. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No.
3, pp. 137–142, May–June, 1999. 相似文献
3.
Sampling hydrocarbon fluids from a reservoir during an early phase of formation testing (typically during interruptions in
drilling) represent an important step in formation evaluation targeting the characterization of composition and pressure/volume/temperature
(PVT) properties of petroleum reserves required for their efficient development. A sampling job is usually accomplished with
a tool, the formation tester, which can be conveyed downhole on a wireline cable, drill-pipe, or tubing. This tool has a probe
and a pump allowing for the production of reservoir fluid from a small spot of a borehole wall covered by filtercake or mudcake
deposited during drilling. The filtercake is built by the invasion of mud filtrate into the formation under pressure overbalance
created by the mud column inside the wellbore. For this reason, after drilling, each wellbore is surrounded by a cylindrical
zone saturated with mud filtrate and, prior to obtaining a sample of virgin formation fluid, cleanup production must be initiated
to overcome the consequences of invasion. A 3D model of flow and contamination transport during cleanup production is considered
in this article. The model assumes a piston-like displacement and no filtrate leakage through mudcake. This model leads to
a multiscale problem of flow and transport in porous media with geometrical and hydrodynamic singularities. A full sensitivity
analysis of its solutions has been carried out versus the initial depth of filtrate invasion and the viscosity contrast between
the formation fluid and invaded mud filtrate. The numerical modeling has revealed two phases of cleanup production. During
the early phase, the contamination of produced fluid is predominantly affected by a circumferential contamination transport.
During the later phase, the evolution of contamination is controlled mainly by mud-filtrate displacement vertically. In the
absence of viscosity contrast, both phases of cleanup can be described by exponential laws for the contamination versus the
produced volume with exponents matching the empirical correlation (−5/12) and the far-field pseudospherical flow pattern (−2/3)
for the early and late phases of cleanup, respectively. In the presence of viscosity contrast, the far-field asymptote holds
whereas the circumferential regime of cleanup is strongly affected by the viscosity ratio. The application of solutions found
to the cleanup production monitoring is briefly described. 相似文献
4.
Models of the residual oil saturation distribution are proposed for linear, axisymmetric, and general flows. The steady displacing
fluid flow model makes it possible to find equilibrium residual oil saturation distributions corresponding to given flow regimes
by treating the porous medium with capillary-trapped oil as a medium with permeability that depends on the displacement conditions.
The dynamics of the mobilized globules of the residual oil are excluded from consideration. The simulation results indicate
that the residual oil saturation distribution after stimulation of the wash-out zone by means of enhanced oil recovery techniques
is generally essentially nonuniform.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 98–104, May–June, 2000. 相似文献
5.
V. E. Zakhvataev 《Fluid Dynamics》2000,35(2):191-199
Some aspects of the problem of the stability and the nature of the secondary regimes of a plane two-layer Poiseuille flow
of viscous dielectric fluids between horizontal electrodes with a constant potential difference are considered. A linear analysis
shows that the electrostatic field can induce the growth of perturbations with an asymptotically small wavenumber when the
dielectric permeabilities of the fluids are different. On the assumption that the perturbation wavelength is large as compared
with the thickness of one of the layers and comparable with the thickness of the other in order of magnitude, one of the possible
mechanisms of development of finite fluctuations is investigated. Within the framework of this mechanism the initial mathematical
mdoel can be reduced to an integrodifferential evolutionary Kuramoto-Sivashinsky-type equation describing the behavior of
the fluid interface. The periodic solutions of this equation, which are investigated numerically, are bounded and fairly diverse.
Krasnoyarsk. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 2, pp. 45–55, March–April,
2000. 相似文献
6.
The stability of the interface between two immiscible fluids of different density which occupy a plane horizontal layer performing
harmonic horizontal oscillations is considered. Within the framework of the ideal fluid model a transformation reducing the
problem of small plane perturbations to the Mathieu equation is found. Resonance instability domains associated with the formation
of capillary-gravitational waves are investigated. A model which takes into account dissipation processes due to the presence
of viscous friction is constructed. The role of the viscous dissipation in suppressing resonance instability is discussed.
Perm’. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 25–31, May–June, 1998.
The work was carried out with partial support from the Russian Foundation for Basic Research (project No. 95-01-00386). 相似文献
7.
The physical effect of multiphase fluid distribution and flow at permeability boundaries has not been fully investigated,
particularly at the pore scale (1–100 μm), although such behaviour can significantly affect the overall scaled-up reservoir
trapping capacity and production performance. In this article, microscale physical models have been used to qualitatively
study the pore scale flow events at permeability boundaries, both high to low and vice versa, to gain a better understanding
of the role of these boundaries and water saturation on multiphase displacement behaviour at the pore scale. We have used
etched glass models of stripes of large and small (a factor of two) pores with circular matrix. Capillary pressure, which
is the controlling parameter is itself dependant on pore size and its spatial distribution, the magnitude of the interfacial
tensions and the wettability between the fluids and the solid surface of the models. Sometimes, the only way the non-wetting
fluid can penetrate the boundary is through a fortuitous leakage, whereby the presence of an initial saturation reduces the
controlling capillary pressure. Examples are demonstrated including mechanisms of end-effects and how capillary boundary resistance
(due to capillary forces) can be broken down and fluid movement across the boundary can develop. These micromodel experiments
show vividly that connate water can assist in these processes, particularly oil trapping and leakage of water across a permeability
boundary. 相似文献
8.
The interacting capillary bundle model proposed by Dong et al. [Dong, M., Dullien, F.A.L., Zhou, J.: Trans. Porous Media 31, 213–237 (1998); Dong, M., Dullien, F.A.L., Dai, L., Li, D.: Trans. Porous Media 59, 1–18 (2005); Dong, M., Dullien, F.A.L., Dai, L., Li, D.: Trans. Porous Media 63, 289–304 (2006)] has simulated correctly various aspects of immiscible displacement in porous media, such as oil production
histories at different viscosity ratios, the effects of water injection rate and of the oil–water viscosity ratio on the shape
of the displacement front and the independence of relative permeabilities of the viscosity ratio. In the interacting capillary
bundle model pressure equilibrium was assumed at any distance x measured along the bundle. Interaction between the capillaries also results in transfer of fluids across the capillaries.
In the first part of this paper the process of fluid transfer between two capillaries is analysed and an algebraic expression
for this flow is derived. Consistency with the assumption of pressure equilibration requires that all transfer must take place
at the positions of the oil/water menisci in the tubes without any pressure drop. It is shown that fluid transfer between
the tubes has no effect on the predictions obtained with the model. In the second part of the paper the interacting tube bundle
model is made more realistic by assuming fluid transfer between the tubes all along the single phase flow regions across a
uniform resistance, resulting in pressure differences throughout the single phase regions between the fluids present in the
different tubes. The results of numerical simulations obtained with this improved interacting capillary bundle model show
only small differences in the positions of the displacement front as compared with the predictions of the idealized model. 相似文献
9.
Yu. I. Kapranov 《Journal of Applied Mechanics and Technical Physics》2000,41(2):309-316
The motion of fluids with suspended particles in porous media is considered. A mathematical model for the interaction of a
monodisperse suspension with a porous structure is proposed. Changes in the parameters of the medium and the flow are studied
for equilibrium regimes.
Lavrent'ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 2, pp. 113–121, March–April, 2000. 相似文献
10.
Exact solutions are obtained for a number of two-dimensional problems of steady-state fluid flow to a lateral hole in a reservoir
with a quiescent bottom fluid of higher density or with a fluid of lower density at the reservoir top
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 5, pp. 114–126, September–October, 2008. 相似文献
11.
F. I. Lukhtura 《Fluid Dynamics》1994,29(4):585-588
The possibility of critical gas flow from Laval nozzles in overexpanded regimes behind a bridge shock is investigated theoretically
with and without allowance for viscous mixing at the edge of the jet. The influence of the mixing effect and flow separation
from the nozzle walls on the critical flow conditions is analyzed. It is shown experimentally that these regimes coincide
closely with the displacement of the normal shock to the nozzle exit and cessation of the emission by the jet of a discrete
tone.
Mariupol. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 4, pp. 180–184, July–August,
1994. 相似文献
12.
I. A. Kozulin V. V. Kuznetsov 《Journal of Applied Mechanics and Technical Physics》2011,52(6):956-964
This paper presents an experimental study of the structure of an upward gas-liquid flow in a vertical microchannel with a
cross-sectional dimension of 0.67 × 2.00 mm and a length of 0.5 m. The tests were performed in the ranges of reduced rates of nitrogen 0.04–11.00 m/sec and water 0.07–0.41 m/sec. Using the method of two-beam laser scanning, we identified the main flow regimes (slug-bubble, slug, transient, emulsion,
and annular) and determined the statistical characteristics of the two-phase flow. A map of flow regimes was constructed,
the dependence of slug velocity on the reduced mixture velocity was obtained, and the friction factor for an upward gas-liquid
flow in a microchannel was measured. 相似文献
13.
The development of the crack opening process and the dimensions of the open-crack zone are determined by the dynamics of the
pressure variation in the injected fluid. Peaking regimes, corresponding to the unbounded growth of one of the characteristics
of the process in a finite time, are of special practical interest. These regimes are examined within the framework of the
nonlinear one-dimensional problem on the basis of a continuum model of flow through fractured porous media.
Sverdlovsk. Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 115–120, September–October,
1988. 相似文献
14.
The effect of heterogeneities on miscible and immiscible flood displacements in 2D bead packs in quadrant form, 2 × 2 block
heterogeneity, with either a permeability or a wettability contrast is the subject of this paper. The physical processes occurring
during miscible and immiscible flow and displacement within permeability and wettability quadrant bead pack models have been
studied experimentally. This geometry occurs in a number of situations relevant to hydrocarbon production: particularly faults
where adjacent rocks have large permeability contrasts with rapid changes, in the laboratory with core butting, in reservoir
simulation where grid blocks have different permeability and in reservoirs having near-wellbore damage problems. The model
quadrants 1–4, had 1 and 4 and 2 and 3 with identical properties, either in permeability or wettability. Reported are complete
unit mobility miscible displacements, then the effects of viscosity differences (mobility modifiers) and finally immiscible
displacements on displacement patterns for initial linear injection. The experiments demonstrate that nodal flow occurs for
both miscible and immiscible flow, but for immiscible flow there are boundary effects due to capillary pressure differences
created by water saturation changes or wettability contrasts which can leave patches of isolated fluid within a quadrant.
The displacement patterns for the different models and fluids change significantly with the viscosity and wettability changes,
particularly for the immiscible displacements. This is due to the changing capillary pressure between the quadrant blocks
as the water saturation change. These are difficult to address in numerical modelling but should be accounted for. Other effects
include coupling of all physical processes governing the flow through the node and creations of microzones of trapped residual
oil. Our displacement patterns can therefore be a valuable verification benchmark tool for numerical modelling and a calibration
data source for those wishing to simulate the effects of capillary pressure under differing wettability conditions and for
those investigating upscaling modelling procedures. However, the possible loss of physical reality when averaging must always
be considered. 相似文献
15.
Heat transfer and resistance in the case of laminar flow of inert gases and liquids in a circular tube were considered in [1–4], the justification of the use of boundary-layer type equations for investigating two-dimensional flows in tubes being provided in [4]. The flow of strongly viscous, chemically reacting fluids in an infinite tube has been investigated analytically and numerically in the case of a constant pressure gradient or constant flow rate of the fluid [5–8]. An analytic analysis of the flow of viscous reacting fluids in tubes of finite length was made in [9, 10]. However, by virtue of the averaging of the unknown functions over the volume of the tube in these investigations, the allowance for the finite length of the tube reduced to an analysis of the influence of the time the fluid remains in the tube on the thermal regime of the flow, and the details of the flow and the heat transfer in the initial section of the tube were not taken into account. In [11], the development of chemical reactions in displacement reactors were studied under the condition that a Poiseuille velocity profile is realized and the viscosity does not depend on the temperature or the concentration of the reactant; in [12], a study was made of the regimes of an adiabatic reactor of finite length, and in [13] of the flow regimes of reacting fluids in long tubes in the case of a constant flow rate. The aim of the present paper is to analyze analytically and numerically in the two-dimensional formulation the approach to the regimes of thermal and hydrodynamic stabilization in the case of the flow of viscous inert fluids and details of the flow of strongly viscous reacting fluids.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 17–25, January–February, 1930. 相似文献
16.
Design of a separation-free airfoil with outer-flow suction over a certain range of angles of attack
The problem of the design of an airfoil with slot air suction from the outer flow for a prescribed velocity distribution over
the airfoil contour that ensures the absence of flow separation over a given range of angles of attack is formulated and solved.
The proposed combined numerical and analytical method of airfoil design within the framework of the inviscid incompressible
fluid model is based on the theory of inverse problems of aerohydrodynamics. Separationless flow past the airfoil is achieved
by eliminating the falling velocity intervals from the specified velocity distribution in two given flow regimes. The flow
past an airfoil with outer-flow suction is determined not only by the angle of attack as for an impermeable airfoil but also
by the value of the suction mass flow. The slot is modeled by an annular channel with constant velocities on the walls. To
satisfy the problem solvability conditions, free parameters are introduced into the initial velocity distribution. Examples
of airfoil design are given.
Kazan, Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 4, pp. 185–191, July–August,
2000. 相似文献
17.
Yu-Shu Wu Bitao Lai Jennifer L. Miskimins Perapon Fakcharoenphol Yuan Di 《Transport in Porous Media》2011,88(2):205-223
Recent laboratory studies and analyses (Lai et al. Presented at the 2009 Rocky Mountain Petroleum Technology Conference, 14–16
April, Denver, CO, 2009) have shown that the Barree and Conway model is able to describe the entire range of relationships between flow rate and
potential gradient from low- to high-flow rates through porous media. A Buckley and Leverett type analytical solution is derived
for non-Darcy displacement of immiscible fluids in porous media, in which non-Darcy flow is described using the Barree and
Conway model. The comparison between Forchheimer and Barree and Conway non-Darcy models is discussed. We also present a general
mathematical and numerical model for incorporating the Barree and Conway model in a general reservoir simulator to simulate
multiphase non-Darcy flow in porous media. As an application example, we use the analytical solution to verify the numerical
solution for and to obtain some insight into one-dimensional non-Darcy displacement of two immiscible fluids with the Barree
and Conway model. The results show how non-Darcy displacement is controlled not only by relative permeability, but also by
non-Darcy coefficients, characteristic length, and injection rates. Overall, this study provides an analysis approach for
modeling multiphase non-Darcy flow in reservoirs according to the Barree and Conway model. 相似文献
18.
The effect of the scheme of fluid injection into a stratum on the length and the hydraulic drag of the initial portion of
the flow through the porous medium and on the flow rate intercepted by a drainage slit separating the stratum from and end
wall is investigated. The asymptotics of large and small values of the hydraulic conductivity coefficient of this slit are
constructed.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 60–67, January–February,
1999.
The work was carried out at the Moscow State Chemical Industry Academy. 相似文献
19.
Somenath Ganguly 《Transport in Porous Media》2010,84(1):201-218
During waterflooding of a fractured formation, water may channel through the fracture or interconnected network of fractures,
leaving a large portion of oil bearing rock unswept. One remedial practice is injection of a gelling solution into the fracture.
Such placement of a gelling mixture is associated with leak-off from the fracture face into the adjoining matrix. Design of
a gel treatment needs understanding of the flow of gelling mixture in and around the fracture. This flow is addressed here
for Cr(III)–partially hydrolyzed polyacrylamide formulation through experiments and conceptual model. A fractured slab was
used to develop a lab-model, where the flow along the fracture and simultaneous leak-off into the matrix can be controlled.
Also, the fracture and matrix properties had to be evaluated individually for a meaningful analysis of the displacement of
gelling solution. During this displacement, the gelling fluid leaked off from the fracture into the matrix as a front, resulting
in a decreasing velocity (and pressure gradient) along the fracture. With pressure in the fracture held constant with time,
the leak-off rate decreased as the viscous front progressed into the matrix. The drop in leak-off rate was rapid during the
initial phase of displacement. A simple model, based on the injection of a viscous solution into the dual continua, could
explain the displacement of Cr(III)–polyacrylamide gelling mixture through the fractured slab. This study rules out any major
complication from the immature gelling fluid, e.g., build-up of cake layer on the fracture face. The model, due to its simplicity
may become useful for quick sizing of gel treatment, and any regression-based evaluation of fluid properties in a fracture
for other applications. 相似文献
20.
The linear stability of flow in a horizontal fluid layer is investigated within the framework of thermoacoustic convection.
The flow is initiated by a longitudinal temperature gradient and the propagation of an acoustic wave in the fluid. Instability
modes corresponding to perturbations of both plane and longitudinal roller and oblique wave type are detected. Using weakly
nonlinear analysis, it is shown that these regimes develop softly; the stability of various secondary flows is investigated
for small supercriticalities.
Perm’. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 10–21, May–June, 2000.
The work was carried out with partial support from the Program of State Support for Leading Science Schools (grant No. 96-015-96084). 相似文献