Data

The initial concentration (in component unit) for each fraction can be speci­fied as

·         Constant (in domain)

·         Varying in domain

A typical background concentration is 10 g/m³.

For the case with varying in domain you have to prepare a data file containing the concentration (in component unit) before you set up the simulation. The file must be a 2D unstructured data file (dfsu) or a 2D grid data file (dfs2). The area in the data file must cover the model area. If a dfsu-file is used, a piece­wise constant interpolation is used to map the data. If a dfs2-file is used, a bilinear interpolation is used to map the data. In case the input data file con­tains a single time step, this field is used. In case the file contains several time steps, e.g. from the results of a previous simulation, the actual starting time of the simulation is used to interpolate the field in time. Therefore the starting time must be between the start and end time of the file.