In this paper, we present a comparative analysis of non-reactive contaminant flow problem for constant initial concentration in two dimensions by homotopy-perturbation and Variational Iteration method. We provide an approximation of this equation using homotopy-perturbation transformation and solve the resulting linear equations analytically by homotopy-perturbation method (HPM) and Variational...

Principal Investigator: Mark M. Benjamin Department of Civil and Environmental Engineering, Box 352700, University of Washington, Seattle WA, 98195-2700 tel. (206) 543 7645, e-mail [email protected] Co-Investigator: Gregory V. Korshin Department of Civil and Environmental Engineering, Box 352700, University of Washington, Seattle WA, 98195-2700 tel. (206) 543 2394, e-mail [email protected]...

In this paper, a numerical study has been carried out for coupled mass, momentum and heat transfer in the field under effects of natural convection. For this purpose, the unsteady incompressible Navier-Stokes equations with the terms of the Buoyancy forces (due to temperature gradients), energy conservation and concentration (mass) transfer equations have been simultaneously solved using approp...

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....

Computational fluid dynamics (CFD) is potentially a valuable tool for simulating the dispersion of air contaminants in workrooms. However, CFD-estimated airflow and contaminant concentration patterns have not always shown good agreement with experimental results. Thus, understanding the factors affecting the accuracy of such simulations is critical for their successful application in occupation...

In this study, the distribution coefficient of Nickel on Anarak nuclear repository was studied considering effects contaminant concentration, soil particle size, and soil/solution ratio. For purpose, two experiments were designed. The sample collected from inside trench Nuclear Repository by channel method its characteristics determined using ASTM method. batch employed while different concentr...

Arsenic contamination in soils occurs widely in a range of ecosystems resulting from geological origins and anthropogenic activities. On average, arsenic concentration ranges from 5 to 10 mg kg−1 in uncontaminated soils and above 10 mg kg−1 in contaminated soils (Hossain, 2006). Increased buildup of arsenic in irrigated soils has been widely recognized in South and South-east Asia (Brammer and ...

The ivory gull is a high-Arctic species considered endangered in most parts of its breeding range. Ivory gulls must cope with both the reduction of sea ice cover triggered by climate change and increasing contaminant loads due to changes in global contaminant pathways. The objective of this study was to assess the concentration of 14 essential and nonessential trace elements at four colonies of...

The performance of an in-situ groundwater remediation project is a complicated function of many factors, including subsurface flow rates and patterns, diffusion/dispersion, rate of contamination from the source, retardation and rate of degradation of the contaminant(s), availability of co-reactants for degradation, etc. The complexity of the interactions between these phenomena makes it difficu...