In the present study, tried to examine the reactive solute relationships for transport and degradation processes through the rockfill media. By applying the analytical solution of reactive transport, the 1st to 3rd theoretical temporal moments have been extracted then, by using two methods of curve fitting and temporal moment matching, the coefficients of dispersion and degradation have been ex...

In this paper, we use the generalized differentiability concept tostudy the fuzzy transport equation. We consider transport equationin the homogeneous and non-homogeneous cases with fuzzy initialcondition. We also present the solution when speed parameter is a fuzzynumber. Our method is based on the construction of the solutionsby employing Zadeh's extension principle.

This paper presents an approach conducive to an evaluation of the probability density function (pdf) of spatio-temporal distributions of concentrations of reactive solutes (and associated reaction rates) evolving in a randomly heterogeneous aquifer. Most existing approaches to solute transport in heterogeneous media focus on providing expressions for space–time moments of concentrations. In gen...

Analytical solutions have been obtained for both conservative and non-conservative forms of one-dimensional transport and transport-dispersion equations applicable for pollution as a result of a non-conservative pollutant-disposal in an open channel with linear spatially varying transport velocity and nonlinear spatially varying dispersion coefficient on account of a steady unpolluted lateral i...

Abstract. Reactive transport processes in natural environments often involve many ionic species. The diffusivities of species vary. Since assigning different the advection–diffusion equation leads to charge imbalance, a single diffusivity is usually used for all In this work, we apply Nernst–Planck equation, which resolves unequal an electroneutral manner, model reactive transport. To demonstra...

Understanding the fundamentals of arsenic adsorption and oxidation reactions is critical for predicting its transport dynamics in groundwater systems. We completed batch experiments to study the interactions of arsenic with a common MnO2(s) mineral, pyrolusite. The reaction kinetics and adsorption isotherm developed from the batch experiments were integrated into a scalable reactive transport m...

Biofilm-forming microbes have complex effects on the flow properties of natural porous media. Subsurface biofilms have the potential for biotransformation of organic contaminants to less harmful forms, and also to form biobarriers to inhibit contaminant migration in groundwater. To describe the population distribution and movement of bacteria in porous media, we consider the convection-dispersi...

A kinetic model of the Boltzmann equation for chemical reactions without energy barrier is considered here with the aim of evaluating the reaction rate and characterizing the transport coefficient of shear viscosity for the reactive system. The Chapman-Enskog solution of the Boltzmann equation is used to compute the chemical reaction effects, in a flow regime for which the reaction process is c...

The correct characterization of the effective reactive transport dynamics is an important issue for modeling reactive transport on the Darcy scale, specifically in situations in which reactions are localized, that is when different reactions occur in different portions of the porous medium. Under such conditions the conventional approach of homogenizing only the porous medium chemistry is not a...

Sediment transport under unsteady flow condition is studied experimentally. In the first step, sediment transport under different steady flow conditions was measured and an empirical equation was derived for its calculation. In the next step, two continuous and three stepwise hydrographs were generated in the flume, and their sediment transport rate was measured. The continuous hydrographs were...