DSM2 is a one-dimensional mathematical model for dynamic simulation of tidal hydraulics, water quality, and particle tracking in a network of riverine or estuarine channels. DSM2 can calculate stages, flows, velocities, transport of individual particles, and mass transport processes for conservative and non-conservative constituents, including salts, water temperature, dissolved oxygen (DO), and dissolved organic carbon (DOC).
The DSM2 online documentation is available at the following link: DSM2 Documentation.
On Windows, just unzip the DSM2 zip file to a folder of your choice.
The partial differential equations of mass and momentum in the DSM2 hydrodynamic model component (HYDRO) are based on an implicit finite difference scheme. As a one-dimensional formulation, the channel length is divided into discrete reaches and the partial differential equations are transformed into finite difference forms for the discrete reaches by integrating numerically in time and space. The resulting equations are then linearized over a single iteration in terms of incremental changes in unknown variables (flow rate and water level) using approximations from truncated series, representing a function as an infinite sum of terms calculated from the values of its derivatives at a single point. When the discretized equations are written for all computational cells at the current time and the next time lines, it forms a system of equations which are solved simultaneously using an implicit algorithm.
The DSM2 water quality numerical solution (QUAL) is based on a model in which advection dispersion equation is solved numerically using a coordinate system where computational nodes move with the flow. The Qual module uses a Lagrangian approach, which is originally based on Branched Lagrangian Transport Model (BLTM).
The DSM2 GTM (Generalized Transport Model) component solves the advection-dispersion equation for multiple constituents using a semi-implicit finite volume scheme, unlike the QUAL module which uses the Lagrangian approach.
The DSM2 HYDRO-GTM couples HYDRO and GTM, and it solves the hydrodynamic and water quality equations at the same time. This coupling allows operating rules with water quality constraints.
If you find any issues, please report them on the GitHub Issues page.