LAGCARTW - A random walk particle advection-diffusion model

LAGCARTW (Lagrange Cartesian suite for Windows) provides a simple method fo r simulating and understanding diffusion using computer animations of rando m walk particles. The model is useful for teaching and demonstration purpos es, but may also be used in an investigative mode-the suite optionally prod uces output files of particle positions which can be used in subsequent ana lysis. Current velocities (defined as a series of tidal harmonics) are defi ned over the model domain, and particles can be discharged from a series of outfalls, reflected or absorbed by boundaries, and allowed to decay. The p rogram also allows a variable diffusion coefficient in the vertical plane. The input file can be altered quite easily via a separate interactive progr am. A series of demonstration files, used to illustrate examples of diffusi on problems, are provided. (C) 2000 Elsevier Science Ltd. All rights reserv ed.