In the present study, analytical solutions are developed for three-dimensional advection-dispersion equation (ADE) in semi-infinite adsorbing saturated homogeneous porous medium with time dependent dispersion coefficient. It means porosity of the medium is filled with single fluid(water). Dispersion coefficient is considered proportional to seepage velocity while adsorption coefficient inversel...

In the present study, analytical solutions are obtained for two-dimensional advection dispersion equation for conservative solute transport in a semi-infinite heterogeneous porous medium with pulse type input point source of uniform nature. The change in dispersion parameter due to heterogeneity is considered as linear multiple of spatially dependent function and seepage velocity whereas seepag...

In the present study, analytical solutions are developed for three-dimensional advection-dispersion equation (ADE) in semi-infinite adsorbing saturated homogeneous porous medium with time dependent dispersion coefficient. It means porosity of the medium is filled with single fluid(water). Dispersion coefficient is considered proportional to seepage velocity while adsorption coefficient inversel...

The aim of this case study is to examine the surface layer CO2 budget and possible impacts of advection on the 20 km scale on estimates of net ecosystem–atmosphere exchange (NEE) of CO2 under windy conditions. The advection terms in the CO2 mixing ratio conservation equation are computed using data from two flux towers 20 km apart in a forested area in Wisconsin, USA. The data are analyzed when...

For decades forecasters in the Queensland Regional Forecast Office of the Australian Bureau of Meteorology have been using winds that turn with height as a rainfall diagnostic, with good success in the subtropics and tropics. The diagnostic is based on the relationship between thermal advection (with its implied isentropic ascent or descent) and geostrophic winds that turn with height. This pap...

An orthogonal terrain-following coordinate (OS coordinate) was proposed by Li et al. (2013) to reduce the advection errors in the classic σ-coordinate. The OS coordinate can smooth the vertical layers above the steep terrain as well as create the orthogonal terrain-following grids in the vertical. The idealized advection experiments in Li et al. (2013) validated that the OS coordinate can signi...

In this paper, we unify advection and diffusion into a single hyperbolic system by extending the firstorder system approach introduced for the diffusion equation in [J. Comput. Phys., 227 (2007) 315-352] to the advection-diffusion equation. Specifically, we construct a unified hyperbolic advection-diffusion system by expressing the diffusion term as a first-order hyperbolic system and simply ad...

Mass spreading of non-reactive tracers in fractured bedrock can be described by a combination of molecular diffusion, hydrodynamic dispersion, and heterogeneous advection. These spreading mechanisms are fundamentally different in their behavior and, therefore, must be measured separately for reliable predictions of transport to be made. To separate the influence of these mechanisms, to the exte...