Boundary/Initial Conditions

Apart from the actual structure of the open channel system and the flow information calculated by 1D Solver, there are a number of user input water quality relationships that are required by 1D Water Quality Solver.

Boundary conditions are required to be input to the model at inflow boundaries, i.e. at upstream boundaries for river systems and at both upstream and downstream boundaries for tidal systems.

In general the boundary conditions must be correctly specified since the uniqueness of the solution depends upon them. Irregularities in data can cause oscillations and it is often advisable to use smoothed concentration/time data.

There is also an optional internal boundary condition, a source node. 1D Water Quality Solver allows the user to either force a concentration-time function at an internal node or simply add this concentration to the ambient pollutant concentration already at the node. Again, this information is provided by the user in a 1D Water Quality input file.

Please note that editing the Water Quality data for the upstream and downstream boundary conditions is possible by both using the Flood Modeller interface and editing the 1D Water Quality data file in a text editor. Editing a Source is currently possible by editing the 1D Water Quality data file in a text editor as described in the Source section.

Initial conditions are also required by 1D Water Quality Solver. These are represented by the pollutant concentration-node data and are entered by the user into an 1D Water Quality input file.

For details on how to construct 1D Water Quality data files consult the following sections:

Preparing a Water Quality Datafile

Datafile Layout

General Data

Initial Conditions

Overview

Technical Background

Related Topics

Preparing a Water Quality Datafile

Datafile Layout

General Data

Initial Conditions