The perifusion apparatus is an experimental tool used to model information transfer in endocrine systems. The major drawback of the penfusion system derives from the dispersion, diffusion and mixing of the hormone within the apparatus which distort the original released hormone concentration profile. In this paper we develop a mathematical model of the perifusion system that accounts for a numb...

The propagation of a signal in a continuous medium and the associated evolution of error is of prime importance in many applications of applied physics. There have been many efforts in analyzing error dynamics, using method attributed to von Neumann [1,2], that is readily applied for linear equations and in quasilinearized form for non-linear equations. The main assumption for linear problems i...

We describe briefly how a third-orderWeighted Essentially Nonoscillatory (WENO) scheme is derived by coupling aWENO spatial discretization scheme with a temporal integration scheme. The scheme is termed WENO3. We perform a spectral analysis of its dispersive and dissipative propertieswhenused to approximate the 1D linear advection equation anduse a technique of optimisation to find the optimal ...

The spreading of oil in an open ocean may cause serious damage to a marine environmental system. Thus, an accurate prediction of oil spill is very important to minimize coastal damage due to unexpected oil spill accident. The movement of oil may be represented with a numerical model that solves an advection-diffusion-reaction equation with a proper numerical scheme. In this study, the spilled o...

This work presents a new adaptive multilevel approximation of the gradient operator on a recursively refined spherical geodesic grid. The multilevel structure provides a simple way to adapt the computation to the local structure of the gradient operator so that high resolution computations are performed only in regions where singularities or sharp transitions occur. This multilevel approximatio...

The fractional advection-dispersion equation (FADE) known as its non-local dispersion, is used in groundwater hydrology and has been proven to be a reliable tool to model the transport of passive tracers carried by fluid flow in a porous media. In this paper, compact structures of FADE are investigated by means of the homotopy perturbation method with consideration of a promising scheme to calc...

242 A dispersion are considered to be the dominant mechanisms of solute transport in the vadose zone, i.e., the variably saturated layer of soils and sediments between the soil surface and groundwater table (Jury and Flühler, 1992). Advection is associated with the average water fl ux or velocity, whereas hydrodynamic dispersion is modeled using an analog of Fick’s law corresponding to the Brow...

two-dimensional hydrodynamic and advection-dispersion simulations were carried out toidentify the appropriate locations of inlet and outlet for cool seawater discharges from the proposed liquefiednatural gas (lng) terminal using mike-21 suites of software. the model simulations were validated bycomparing the observed and simulated hydrodynamics in terms of water depths, current speeds and direc...

We consider transport of a solute that undergoes a nonlinear heterogeneous reaction: after reaching a threshold concentration value, it precipitates on the solid matrix to form a crystalline solid. The relative importance of three key pore-scale transport mechanisms (advection, molecular diffusion, and reaction) is quantified by the Péclet (Pe) and Damköhler (Da) numbers. We use multiple-scale ...

The present work solves two-dimensional Advection-Dispersion Equation (ADE) in a semi-infinite domain. A variable source concentration is regarded as the monotonic decreasing function at the source boundary (x=0). Depth-dependent variables are considered to incorporate real life situations in this modeling study, with zero flux condition assumed to occur at the exit boundary of the domain, i.e....