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991.
992.
A new phenomenological mathematical model of the propagation of high- and low-salinity solutions through inhomogeneous aquifers is proposed. The model consists of interrelated equations of two-phase flow and diffusive mass transfer through a porous medium in a region with a traveling boundary. Features of different contamination scenarios of are analyzed with reference to particular examples. 相似文献
993.
994.
Disappearance of interfaces in finite time 总被引:2,自引:0,他引:2
For the solution of filtration equation with a density which is decreasing at infinity fast enough we found that the interface disappears in finite time.
Sommario Si considera un problema di filtrazione con densità che decresce all'infinito in modo sufficientemente rapido. Si dimostra che il contorno libero sparisce in tempo finito.相似文献
995.
This study has been conducted to compare two different numerical models for the evaluation of the performance characteristics of a diffuser‐nozzle based piezoelectric micropump. Here, the transient displacements of the membrane and the flow characteristics in the piezoelectric micropump have been closely investigated with the FSI model and the prescribed deformation model for two different frequencies. It has been found that the behaviour of the membrane computed with the FSI model is not in accordance with that with the prescribed deformation model, and that the net flow rate with the FSI model is larger than that with the prescribed deformation model. Therefore, the choice of numerical model is very important in conducting numerical analysis for piezoelectric micropumps. The results of this study can be utilized as basic data for the design and analysis of piezoelectric micropumps. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
996.
含压电片层合板的静变形控制 总被引:3,自引:0,他引:3
借助阶梯函数,建立了含有任意分布的用作执行器的的压电片的层合板弯曲方程,然后利用该方程,进行了层合板静变形控制的研究,最后给实例,用“遗传+配点”法对压电片的位置和尺寸进行了优化。结果表明,用压电片作执行器,用“遗传+配点”法进行优化是对板进行静力变形控制的一条有效途径。 相似文献
997.
Jong Uhn Kim 《Journal of Differential Equations》2006,220(1):163-194
In this paper, we discuss an initial-boundary value problem and a Cauchy problem for the stochastic porous medium equation. Our basic estimates are based on the known results due to (Math. Sbornik 67 (1965) 609-642, Arch. Rational Mech. Anal. 25 (1967) 64-80). By the procedure developed in (Trans. Amer. Math. Soc. 354 (2001) 1117-1135), we obtain solutions over the given probability space rather than martingale solutions. We will also establish the existence of invariant measures when the space domain is bounded. 相似文献
998.
G. V. Filatov 《International Applied Mechanics》2006,42(3):331-335
A new optimization model is proposed to design corrosion-affected structures with limited life. The optimization problem is
stated as a nonlinear-programming problem. The mass of the structure is minimized. The design is considered optimal when physical
wear and obsolescence arrive simultaneously. A smooth cylindrical shell compressed in the longitudinal direction is used to
illustrate the model
__________
Translated from Prikladnaya Mekhanika, Vol. 42, No. 3, pp. 97–101, March 2006. 相似文献
999.
This paper is devoted to the mathematical analysis of the miscible displacement of a set of radionuclides in a flow occurring in a heterogeneous porous medium. The flow is governed by Darcy's law, and the motion of the chemical species is given by a nonclassical advection-diffusion-reaction equations system. The novelty of the model lies in the adsorption phenomenon that leads to a time derivative of a nonlinear term in these equations. A semi-discretization method is used to establish the existence of weak solutions to this system. Uniform L∞-estimates on the solutions are specified. 相似文献
1000.
Based on the two-energy equation model, taking into account viscous dissipation due to the interaction between solid skeleton and pore fluid flow, temperature expressions of the solid skeleton and pore fluid flow are obtained analytically for the thermally developing forced convection in a saturated porous medium parallel plate channel, with walls being at constant temperature. It is proved that the temperatures of the two phases for the local thermal nonequilibrium approach to the temperature derived from the one-energy equation model for the local thermal equilibrium when the heat exchange coefficient goes to infinite. The temperature profiles are shown in figures for different dimensionless parameters and the effects of the parameters on the local thermal nonequilibrium are revealed by parameter study. 相似文献