the accurate estimation of reaeration rate coefficient, because of its effects on dissolved oxygen in rivers, is one of the most important initial steps of water quality management. the main goal of this paper is to evaluate the effects of reaeration rate coefficient on the river water dissolved oxygen, case study dinachal river, iran. to achieve these aims, water quality samples were collected...

Semi-Lagrangian methods have been around for some time, dating back at least to [3]. Researchers have worked to increase their accuracy, and these schemes have gained newfound interest with the recent widespread use of adaptive grids where the CFL-based time step restriction of the smallest cell can be overwhelming. Since these schemes are based on characteristic tracing and interpolation, they...

A Projection Method for Incompressible Viscous Flow on a Deformable Domain by David Paul Trebotich Doctor of Philosophy in Mechanical Engineering University of California, Berkeley Professor Phillip Colella, Chair 1 A second-order accurate finite difference method is presented for numerical solution of the incompressible Navier-Stokes equations on a deformable domain. The target problem is flow...

We propose a domain decomposition method for advection-diffusionreaction equations based on Nitsche’s transmission conditions. The advection dominated case is stabilized using a continuous interior penalty approach based on the jumps in the gradient over element boundaries. We prove the convergence of the finite element solutions of the discrete problem to the exact solution and we propose a pa...

This article is a review of MPDATA, a class of methods for the numerical simulation of fluid flows based on the sign-preserving properties of upstream differencing. MPDATA was designed originally as an inexpensive alternative to flux-limited schemes for evaluating the advection of nonnegative thermodynamic variables (such as liquid water or water vapour) in atmospheric models. During the last d...

We prove the stability and a priori global and local error analysis for the residual-free bubbles finite element method applied to advection dominated advection-diffusion problems.

Systems in which reaction terms are coupled to diffusion and advection transports arise in a wide range of chemical engineering applications, physics, biology and environmental. In these cases, the components of the unknown can denote concentrations or population sizes which represent quantities and they need to remain positive. Classical finite difference schemes may produce numerical drawback...

We derive local error estimates for the discretization of optimal control problems governed by linear advection-diffusion partial differential equations (PDEs) using the streamline upwind/Petrov Galerkin (SUPG) stabilized finite element method. We show that if the SUPG method is used to solve optimization problems governed by an advection-dominated PDE the convergence properties of the SUPG met...

We consider an exponentially fitted discontinuous Galerkin method for advection dominated problems and propose a block solver for the resulting linear systems. In the case of strong advection the solver is robust with respect to the advection direction and the number of unknowns.