Articles de revues : « Periodic porous media »

1

Alcocer, F. J., V. Kumar et P. Singh. « Permeability of periodic porous media ». Physical Review E 59, n^o 1 (1 janvier 1999) : 711–14. http://dx.doi.org/10.1103/physreve.59.711.

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Saeger, R. B., L. E. Scriven et H. T. Davis. « Transport processes in periodic porous media ». Journal of Fluid Mechanics 299 (25 septembre 1995) : 1–15. http://dx.doi.org/10.1017/s0022112095003399.

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The Stokes equation system and Ohm's law were solved numerically for fluid in periodic bicontinuous porous media of simple cubic (SC), body-centred cubic (BCC) and face-centred cubic (FCC) symmetry. The Stokes equation system was also solved for fluid in porous media of SC arrays of disjoint spheres. The equations were solved by Galerkin's method with finite element basis functions and with elliptic grid generation. The Darcy permeability k computed for flow through SC arrays of spheres is in excellent agreement with predictions made by other authors. Prominent recirculation patterns are found for Stokes flow in bicontinuous porous media. The results of the analysis of Stokes flow and Ohmic conduction through bicontinuous porous media were used to test the permeability scaling law proposed by Johnson, Koplik & Schwartz (1986), which introduces a length parameter Λ to relate Darcy permeability k and the formation factor F. As reported in our earlier work on the SC bicontinuous porous media, the scaling law holds approximately for the BCC and FCC families except when the porespace becomes nearly spherical pores connected by small orifice-like passages. We also found that, except when the porespace was connected by the small orifice-like passages, the permeability versus porosity curve of the bicontinuous media agrees very well with that of arrays of disjoint and fused spheres of the same crystallographic symmetry.

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3

Kuznetsov, Sergey V. « Fundamental Solutions for Periodic Media ». Advances in Mathematical Physics 2014 (2014) : 1–4. http://dx.doi.org/10.1155/2014/473068.

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Necessity for the periodic fundamental solutions arises when the periodic boundary value problems should be analyzed. The latter are naturally related to problems of finding the homogenized properties of the dispersed composites, porous media, and media with uniformly distributed microcracks or dislocations. Construction of the periodic fundamental solutions is done in terms of the convergent series in harmonic polynomials. An example of the periodic fundamental solution for the anisotropic porous medium is constructed, along with the simplified lower bound estimate.

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4

Hizi, Uzi, et David J. Bergman. « Molecular diffusion in periodic porous media ». Journal of Applied Physics 87, n^o 4 (15 février 2000) : 1704–11. http://dx.doi.org/10.1063/1.372081.

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5

Wallender, W. W., et D. Buyuktas. « Dispersion in spatially periodic porous media ». Heat and Mass Transfer 40, n^o 3-4 (1 février 2004) : 261–70. http://dx.doi.org/10.1007/s00231-003-0441-0.

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6

Rubinstein, Jacob, et Roberto Mauri. « Dispersion and Convection in Periodic Porous Media ». SIAM Journal on Applied Mathematics 46, n^o 6 (décembre 1986) : 1018–23. http://dx.doi.org/10.1137/0146060.

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Chapman, A. M., et J. J. L. Higdon. « Oscillatory Stokes flow in periodic porous media ». Physics of Fluids A : Fluid Dynamics 4, n^o 10 (octobre 1992) : 2099–116. http://dx.doi.org/10.1063/1.858507.

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LOGAN, J., et V. ZLOTNIK. « Time-Periodic Transport in Heterogeneous Porous Media ». Applied Mathematics and Computation 75, n^o 2-5 (15 mars 1996) : 119–38. http://dx.doi.org/10.1016/0096-3003(95)00120-4.

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9

David Logan, J., et Vitaly Zlotnik. « Time-periodic transport in heterogeneous porous media ». Applied Mathematics and Computation 75, n^o 2-3 (mars 1996) : 119–38. http://dx.doi.org/10.1016/0096-3003(96)90053-3.

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10

Sandrakov, Gennadiy, Andrii Hulianytskyi et Vladimir Semenov. « Modeling of filtration processes in periodic porous media ». Modeling Control and Information Technologies, n^o 5 (21 novembre 2021) : 90–93. http://dx.doi.org/10.31713/mcit.2021.28.

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Modeling of dynamic processes of diffusion and filtration of liquids in porous media are discussed. The media are formed by a large number of blocks with low permeability, and separated by a connected system of faults with high permeability. The modeling is based on solving initial boundary value problems for parabolic equations of diffusion and filtration in porous media. The structure of the media leads to the dependence of the equations on a small parameter. Assertions on the solvability and regularity of such problems and the corresponding homogenized convolution problems are considered. The statements are actual for the numerical solution of this problem with guaranteed accuracy that is necessary to model the considered processes.

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11

Bhattacharya, R. N., V. K. Gupta et H. F. Walker. « Asymptotics of Solute Dispersion in Periodic Porous Media ». SIAM Journal on Applied Mathematics 49, n^o 1 (février 1989) : 86–98. http://dx.doi.org/10.1137/0149005.

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Gupta, Vijay K., et R. N. Bhattacharya. « Solute Dispersion in Multidimensional Periodic Saturated Porous Media ». Water Resources Research 22, n^o 2 (février 1986) : 156–64. http://dx.doi.org/10.1029/wr022i002p00156.

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Larson, R. E., et J. J. L. Higdon. « A periodic grain consolidation model of porous media ». Physics of Fluids A : Fluid Dynamics 1, n^o 1 (janvier 1989) : 38–46. http://dx.doi.org/10.1063/1.857545.

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14

Steen, Paul H., et Cyrus K. Aidun. « Time-periodic convection in porous media : transition mechanism ». Journal of Fluid Mechanics 196 (novembre 1988) : 263–90. http://dx.doi.org/10.1017/s0022112088002708.

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We resolve the disturbance structures that destabilize steady convection rolls in favour of a time-periodic pattern in two-dimensional containers of fluid-saturated porous material. Analysis of these structures shows that instability occurs as a travelling wave propagating in a closed loop outside the nearly motionless core. The travelling wave consists of five pairs of thermal cells and four pairs of vorticity disturbances in the case of a square container. The wave speed of the thermal disturbances is determined by an average base-state velocity and their structure by a balance between convection and thermal diffusion. Interpretation of the ‘exact’ solution is aided by a one-dimensional convection-loop model which correlates (i) point of transition, (ii) disturbance wavenumber, and (iii) oscillation frequency given the base-state temperature and velocity profiles. The resulting modified Mathieu-Hill equation clarifies the role of the vertical pressure gradient, induced by the impenetrable walls, and the role of the base-state thermal layer.

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15

Marmur, Abraham. « Capillary rise and hysteresis in periodic porous media ». Journal of Colloid and Interface Science 129, n^o 1 (avril 1989) : 278–85. http://dx.doi.org/10.1016/0021-9797(89)90440-2.

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Dimitrienko, Yu I., et I. D. Dimitrienko. « Simulation of local transfer in periodic porous media ». European Journal of Mechanics - B/Fluids 37 (janvier 2013) : 174–79. http://dx.doi.org/10.1016/j.euromechflu.2012.09.006.

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17

Allali, Karam, Youssef Joundy, Ahmed Taik et Vitaly Volpert. « Dynamics of Convective Thermal Explosion in Porous Media ». International Journal of Bifurcation and Chaos 30, n^o 06 (mai 2020) : 2050081. http://dx.doi.org/10.1142/s0218127420500819.

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In this paper, we study complex dynamics of the interaction between natural convection and thermal explosion in porous media. This process is modeled with the nonlinear heat equation coupled with the nonstationary Darcy equation under the Boussinesq approximation for a fluid-saturated porous medium in a rectangular domain. Numerical simulations with the Radial Basis Functions Method (RBFM) reveal complex dynamics of solutions and transitions to chaos after a sequence of period doubling bifurcations. Several periodic windows alternate with chaotic regimes due to intermittence or crisis. After the last chaotic regime, a final periodic solution precedes transition to thermal explosion.

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18

FIRDAOUSS, MOUAOUIA, JEAN-LUC GUERMOND et PATRICK LE QUÉRÉ. « Nonlinear corrections to Darcy's law at low Reynolds numbers ». Journal of Fluid Mechanics 343 (25 juillet 1997) : 331–50. http://dx.doi.org/10.1017/s0022112097005843.

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Under fairly general assumptions, this paper shows that for periodic porous media, whose period is of the same order as that of the inclusion, the nonlinear correction to Darcy's law is quadratic in terms of the Reynolds number, i.e. cubic with respect to the seepage velocity. This claim is substantiated by reinspection of well-known experimental results, a mathematical proof (restricted to periodic porous media), and numerical calculations.

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19

Alkharashi, S. A., et Y. Gamiel. « Stability characteristics of periodic streaming fluids in porous media ». Theoretical and Mathematical Physics 191, n^o 1 (avril 2017) : 580–601. http://dx.doi.org/10.1134/s0040577917040092.

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20

Allaire, Grégoire, et Harsha Hutridurga. « Upscaling nonlinear adsorption in periodic porous media – homogenization approach ». Applicable Analysis 95, n^o 10 (27 avril 2015) : 2126–61. http://dx.doi.org/10.1080/00036811.2015.1038254.

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21

Wenzel, Michael. « Stabilization of free surface flows in periodic porous media ». Nonlinear Analysis : Real World Applications 17 (juin 2014) : 265–82. http://dx.doi.org/10.1016/j.nonrwa.2013.12.004.

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22

Dyakonova, N. E., J. A. Odell, Yu V. Brestkin, A. V. Lyulin et A. E. Saez. « Macromolecular strain in periodic models of porous media flows ». Journal of Non-Newtonian Fluid Mechanics 67 (novembre 1996) : 285–310. http://dx.doi.org/10.1016/s0377-0257(96)01483-8.

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23

Timofte, Claudia. « Homogenization results for ionic transport in periodic porous media ». Computers & ; Mathematics with Applications 68, n^o 9 (novembre 2014) : 1024–31. http://dx.doi.org/10.1016/j.camwa.2014.03.009.

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24

Kimura, S., G. Schubert et J. M. Straus. « Instabilities of Steady, Periodic, and Quasi-Periodic Modes of Convection in Porous Media ». Journal of Heat Transfer 109, n^o 2 (1 mai 1987) : 350–55. http://dx.doi.org/10.1115/1.3248087.

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Instabilities of steady and time-dependent thermal convection in a fluid-saturated porous medium heated from below have been studied using linear perturbation theory. The stability of steady-state solutions of the governing equations (obtained numerically) has been analyzed by evaluating the eigenvalues of the linearized system of equations describing the temporal behavior of infinitesimal perturbations. Using this procedure, we have found that time-dependent convection in a square cell sets in at Rayleigh number Ra=390. The temporal frequency of the simply periodic (P(1)) convection at Rayleigh numbers exceeding this value is given by the imaginary part of the complex eigenvalue. The stability of this (P(1)) state has also been studied; transition to quasi-periodic convection (QP2) occurs at Ra ≈ 510. A reverse transition to a simply periodic state (P(2)) occurs at Ra ≈ 560; a slight jump in the frequency of the P(2) state occurs at Ra between 625 and 640. The jump coincides with a second narrow (in terms of Ra) region of quasi-periodicity.

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25

Gruais, Isabelle, et Dan Poliševski. « Thermal flows in fractured porous media ». ESAIM : Mathematical Modelling and Numerical Analysis 55, n^o 3 (mai 2021) : 789–805. http://dx.doi.org/10.1051/m2an/2020087.

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We consider the thermal flow problem occuring in a fractured porous medium. The incompressible filtration flow in the porous matrix and the viscous flow in the fractures obey the Boussinesq approximation of Darcy-Forchheimer law and respectively, the Stokes system. They are coupled by the Saffman’s variant of the Beavers–Joseph condition. Existence and uniqueness properties are presented. The use of the energy norm in describing the Darcy-Forchheimer law proves to be appropriate. In the ε-periodic framework, we find the two-scale homogenized system which governs their asymptotic behaviours when ε → 0 and the Forchheimer effect vanishes. The limit problem is mainly a model of two coupled thermal flows, neither of them being incompressible.

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Trefry, M. G., D. McLaughlin, G. Metcalfe, D. Lester, A. Ord, K. Regenauer-Lieb et B. E. Hobbs. « On oscillating flows in randomly heterogeneous porous media ». Philosophical Transactions of the Royal Society A : Mathematical, Physical and Engineering Sciences 368, n^o 1910 (13 janvier 2010) : 197–216. http://dx.doi.org/10.1098/rsta.2009.0186.

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The emergence of structure in reactive geofluid systems is of current interest. In geofluid systems, the fluids are supported by a porous medium whose physical and chemical properties may vary in space and time, sometimes sharply, and which may also evolve in reaction with the local fluids. Geofluids may also experience pressure and temperature conditions within the porous medium that drive their momentum relations beyond the normal Darcy regime. Furthermore, natural geofluid systems may experience forcings that are periodic in nature, or at least episodic. The combination of transient forcing, near-critical fluid dynamics and heterogeneous porous media yields a rich array of emergent geofluid phenomena that are only now beginning to be understood. One of the barriers to forward analysis in these geofluid systems is the problem of data scarcity. It is most often the case that fluid properties are reasonably well known, but that data on porous medium properties are measured with much less precision and spatial density. It is common to seek to perform an estimation of the porous medium properties by an inverse approach, that is, by expressing porous medium properties in terms of observed fluid characteristics. In this paper, we move toward such an inversion for the case of a generalized geofluid momentum equation in the context of time-periodic boundary conditions. We show that the generalized momentum equation results in frequency-domain responses that are governed by a second-order equation which is amenable to numerical solution. A stochastic perturbation approach demonstrates that frequency-domain responses of the fluids migrating in heterogeneous domains have spatial spectral densities that can be expressed in terms of the spectral densities of porous media properties.

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Alkharashi, Sameh A. « Electrohydrodynamics Instability of Three Periodic Streaming Fluids through Porous Media ». OALib 02, n^o 02 (2015) : 1–12. http://dx.doi.org/10.4236/oalib.1101315.

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Heintz, Alexei, et Andrey Piatnitski. « Osmosis for non-electrolyte solvents in permeable periodic porous media ». Networks and Heterogeneous Media 11, n^o 3 (août 2016) : 471–99. http://dx.doi.org/10.3934/nhm.2016005.

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Angeli, Pierre-Emmanuel, Frederic Ducros, Olivier Cioni et Benoit Goyeau. « DOWNSCALING PROCEDURE FOR CONVECTIVE HEAT TRANSFER IN PERIODIC POROUS MEDIA ». Journal of Porous Media 16, n^o 2 (2013) : 123–35. http://dx.doi.org/10.1615/jpormedia.v16.i2.40.

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Amaral Souto, Hélio P., et Christian Moyne. « Dispersion in two-dimensional periodic porous media. Part I. Hydrodynamics ». Physics of Fluids 9, n^o 8 (août 1997) : 2243–52. http://dx.doi.org/10.1063/1.869365.

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Kostoglou, Margaritis. « Periodic Thermal Behavior of Porous Media under Oscillating Flow Conditions ». Industrial & ; Engineering Chemistry Research 49, n^o 10 (19 mai 2010) : 5006–11. http://dx.doi.org/10.1021/ie9014638.

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Shvidler, M. I. « Multicontinuum description of percolating flow through periodic inhomogeneous porous media ». Fluid Dynamics 23, n^o 6 (1989) : 894–901. http://dx.doi.org/10.1007/bf01051826.

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Yazdchi, K., S. Srivastava et S. Luding. « Microstructural effects on the permeability of periodic fibrous porous media ». International Journal of Multiphase Flow 37, n^o 8 (octobre 2011) : 956–66. http://dx.doi.org/10.1016/j.ijmultiphaseflow.2011.05.003.

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Goldsztein, Guillermo H. « Solute transport in porous media : Dispersion tensor of periodic networks ». Applied Physics Letters 91, n^o 5 (30 juillet 2007) : 054102. http://dx.doi.org/10.1063/1.2760180.

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Logan, J. D., V. A. Zlotnik et S. Cohn. « Transport in fractured porous media with time-periodic boundary conditions ». Mathematical and Computer Modelling 24, n^o 9 (novembre 1996) : 1–9. http://dx.doi.org/10.1016/0895-7177(96)00149-5.

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Lipaev, A. A., et V. A. Chugunov. « Features of periodic temperature profiles in filtrating capillary porous media ». Journal of Engineering Physics 61, n^o 4 (octobre 1991) : 1262–65. http://dx.doi.org/10.1007/bf00872596.

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Shen, L. C., C. Liu, J. Korringa et K. J. Dunn. « Computation of conductivity and dielectric constant of periodic porous media ». Journal of Applied Physics 67, n^o 11 (juin 1990) : 7071–81. http://dx.doi.org/10.1063/1.345056.

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38

Dunn, Keh‐Jim, Gerald A. LaTorraca et David J. Bergman. « Permeability relation with other petrophysical parameters for periodic porous media ». GEOPHYSICS 64, n^o 2 (mars 1999) : 470–78. http://dx.doi.org/10.1190/1.1444552.

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We modeled permeability (k) estimation based on porosity (ϕ), electrical formation factor (F), and nuclear magnetic resonance (NMR) relaxation time (T), using periodic structures of touching and overlapping spheres. The formation factors for these systems were calculated using the theory of bounds of bulk effective conductivity for a two‐component composite. The model allowed variations in grain consolidation (degree of overlap), scaling (grain size), and NMR surface relaxivity. The correlation of the permeability (k) with the predictor a [Formula: see text] was slightly higher than [Formula: see text] (i.e., a correlation coefficient of 0.98 versus 0.95). The exponent b ranged from 1.4 for a pure grain consolidation system to 2 for a pure scaling system. Variations in surface relaxivity are shown to cause significant scatter in the correlations.

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Looker, Jason R., et Steven L. Carnie. « Homogenization of the Ionic Transport Equations in Periodic Porous Media ». Transport in Porous Media 65, n^o 1 (octobre 2006) : 107–31. http://dx.doi.org/10.1007/s11242-005-6080-9.

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40

Hutter, C., A. Zenklusen, R. Lang et Ph Rudolf von Rohr. « Axial dispersion in metal foams and streamwise-periodic porous media ». Chemical Engineering Science 66, n^o 6 (mars 2011) : 1132–41. http://dx.doi.org/10.1016/j.ces.2010.12.016.

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41

Sandrakov, G. V. « HOMOGENIZED MODELS FOR MULTIPHASE DIFFUSION IN POROUS MEDIA ». Journal of Numerical and Applied Mathematics, n^o 3 (132) (2019) : 43–59. http://dx.doi.org/10.17721/2706-9699.2019.3.05.

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Non-stationary processes of mutual diffusion for multiphase flows of immiscible liquids in porous media with a periodic structure are considered. The mathematical model for such processes is initial-boundary diffusion problem for media formed by a large number of «blocks» having low permeability and separated by a connected system of «cracks» with high permeability. Taking into account such a structure of porous media during modeling leads to the dependence of the equations of the problem on two small parameters of the porous medium microscale and the block permeability. Homogenized initial-boundary value problems will be obtained. Solutions of the problems are approximated for the solutions of the initial-boundary value problem under consideration.

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Ravi Kumar, N. « Exergy Analysis of Porous Medium Combustion Engine Cycle ». ISRN Mechanical Engineering 2011 (16 octobre 2011) : 1–6. http://dx.doi.org/10.5402/2011/542840.

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The need of the fossil fuels is ever increasing in the areas of manufacturing, transportation, heating, and electricity. Nearly 90% of the energy requirement in transport sector is met by combustion of fossil fuels only. Porous media (PM) combustion is an effective method, which can increase the combustion efficiency as well as minimize environmental pollution. The present paper is aimed at thermodynamic analysis of ideal IC engine cycles with porous media combustion. Two practically possible cycles, namely, periodic and permanent contact of gas with porous medium are considered, and the ideal cycle analyses are made. It is found that PM engine with periodic contact is more efficient than permanent contact type. The exergy analysis also reveals that the energy loss due to irreversibilities in the periodic contact type is less than that of the permanent contact type. With the help of model calculations and graphs, the performance of these two cycles is compared and optimal operating conditions are also evaluated and presented along with the suggestions for enhancing the performance of homogeneous PM combustion in IC engines.

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Lasseux, Didier, Francisco J. Valdés-Parada et Fabien Bellet. « Macroscopic model for unsteady flow in porous media ». Journal of Fluid Mechanics 862 (10 janvier 2019) : 283–311. http://dx.doi.org/10.1017/jfm.2018.878.

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The present article reports on a formal derivation of a macroscopic model for unsteady one-phase incompressible flow in rigid and periodic porous media using an upscaling technique. The derivation is carried out in the time domain in the general situation where inertia may have a significant impact. The resulting model is non-local in time and involves two effective coefficients in the macroscopic filtration law, namely a dynamic apparent permeability tensor,$\unicode[STIX]{x1D643}_{t}$, and a vector,$\unicode[STIX]{x1D736}$, accounting for the time-decaying influence of the flow initial condition. This model generalizes previous non-local macroscale models restricted to creeping flow conditions. Ancillary closure problems are provided, which allow the effective coefficients to be computed. Symmetry and positiveness analyses of$\unicode[STIX]{x1D643}_{t}$are carried out, showing that this tensor is symmetric only in the creeping regime. The effective coefficients are functions of time, geometry, macroscopic forcings and the initial flow condition. This is illustrated through numerical solutions of the closure problems. Predictions are made on a simple periodic structure for a wide range of Reynolds numbers smaller than the critical value characterizing the first Hopf bifurcation. Finally, the performance of the macroscopic model for a variety of macroscopic forcings and initial conditions is examined in several case studies. Validation through comparisons with direct numerical simulations is performed. It is shown that the purely heuristic classical model, widely used for unsteady flow, consisting of a Darcy-like model complemented with an accumulation term on the filtration velocity, is inappropriate.

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Sandrakov, G. V. « MODELING OF WAVE PROCESSES IN POROUS MEDIA AND ASYMPTOTIC EXPANSIONS ». Journal of Numerical and Applied Mathematics, n^o 2 (2022) : 132–42. http://dx.doi.org/10.17721/2706-9699.2022.2.15.

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Models of wave processes in porous periodic media are considered. It is taken into account that the corresponding wave equations depend on small parameters characterizing the microscale, density, and permeability of such media. The algorithm for determining asymptotic expansions for these equations is given. Estimates for the accuracy of such expansions are presented.

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Daly, K. R., et T. Roose. « Homogenization of two fluid flow in porous media ». Proceedings of the Royal Society A : Mathematical, Physical and Engineering Sciences 471, n^o 2176 (avril 2015) : 20140564. http://dx.doi.org/10.1098/rspa.2014.0564.

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The macroscopic behaviour of air and water in porous media is often approximated using Richards' equation for the fluid saturation and pressure. This equation is parametrized by the hydraulic conductivity and water release curve. In this paper, we use homogenization to derive a general model for saturation and pressure in porous media based on an underlying periodic porous structure. Under an appropriate set of assumptions, i.e. constant gas pressure, this model is shown to reduce to the simpler form of Richards' equation. The starting point for this derivation is the Cahn–Hilliard phase field equation coupled with Stokes equations for fluid flow. This approach allows us, for the first time, to rigorously derive the water release curve and hydraulic conductivities through a series of cell problems. The method captures the hysteresis in the water release curve and ties the macroscopic properties of the porous media with the underlying geometrical and material properties.

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Jun Feng Wang et Wook Ryol Hwang. « Transverse mobility prediction of non-Newtonian fluids across fibrous porous media ». Journal of Composite Materials 45, n^o 8 (22 février 2011) : 883–93. http://dx.doi.org/10.1177/0021998311402255.

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This work is an extension of our previous work [Wang JF and Hwang WR. Permeability prediction of fibrous porous media in a bi-periodic domain. J Compos Mater 2007; 42: 909—929], in which a finite-element fictitious-domain mortar-element technique was developed to investigate the permeability of fibrous porous media in the bi-periodic domain, to non-Newtonian shear-thinning fluid. Considering the amount of shear-thinning, the pressure drop, the fiber microstructure, and the porosity as parameters, we investigate (i) the (normalized) mobility and its dependence on both the amount of shear-thinning and the given pressure drop; (ii) mechanisms leading to the main flow path in a highly shear-thinning fluid in randomly distributed fiber problems, and (iii) inter-tow and intra-tow non-Newtonian flow characteristics in a fiber bundle problem. The dependence of the mobility on shear-thinning has been found to appear completely opposite according to given pressure drop values.

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Huang, Wei, Sima Didari, Yan Wang et Tequila A. L. Harris. « Generalized periodic surface model and its application in designing fibrous porous media ». Engineering Computations 32, n^o 1 (2 mars 2015) : 7–36. http://dx.doi.org/10.1108/ec-03-2013-0085.

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Purpose – Fibrous porous media have a wide variety of applications in insulation, filtration, acoustics, sensing, and actuation. To design such materials, computational modeling methods are needed to engineer the properties systematically. There is a lack of efficient approaches to build and modify those complex structures in computers. The paper aims to discuss these issues. Design/methodology/approach – In this paper, the authors generalize a previously developed periodic surface (PS) model so that the detailed shapes of fibers in porous media can be modeled. Because of its periodic and implicit nature, the generalized PS model is able to efficiently construct the three-dimensional representative volume element (RVE) of randomly distributed fibers. A physics-based empirical force field method is also developed to model the fiber bending and deformation. Findings – Integrated with computational fluid dynamics (CFD) analysis tools, the proposed approach enables simulation-based design of fibrous porous media. Research limitations/implications – In the future, the authors will investigate robust approaches to export meshes of PS models directly to CFD simulation tools and develop geometric modeling methods for composite materials that include both fibers and resin. Originality/value – The proposed geometric modeling method with implicit surfaces to represent fibers is unique in its capability of modeling bent and deformed fibers in a RVE and supporting design parameter-based modification for global configuration change for the purpose of macroscopic transport property analysis.

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Cheng, Ping, et Chin-Tsau Hsu. « The Effective Stagnant Thermal Conductivity of Porous Media with Periodic Structures ». Journal of Porous Media 2, n^o 1 (1999) : 19–38. http://dx.doi.org/10.1615/jpormedia.v2.i1.20.

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Amaral Souto, Hélio P., et Christian Moyne. « Dispersion in two-dimensional periodic porous media. Part II. Dispersion tensor ». Physics of Fluids 9, n^o 8 (août 1997) : 2253–63. http://dx.doi.org/10.1063/1.869347.

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Escher, Joachim, et Georg Prokert. « Stability of the equilibria for spatially periodic flows in porous media ». Nonlinear Analysis : Theory, Methods & ; Applications 45, n^o 8 (septembre 2001) : 1061–80. http://dx.doi.org/10.1016/s0362-546x(99)00434-4.

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