Schematic procedure for calibration

Schematic procedure for calibration
SPRING-help >> Structure of the individual model types >> Construction of a 2D-Model >> Step 4: Calibration of a groundwater model >>

  1. Transferring the automatically iterated K-values to the model file

  1. Model checking

  1. Flow calculation

  1. Comparison of the groundwater levels from measured data with the calculated groundwater levels,

- if available, with representation of the differences (circle plot) at the measuring points.

  1. Change of the K-values in certain areas according to the course of the isolines

- if the calculated potential heads are too high, the soil is too impermeable, i.e. the K-values may need to be increased

- if the calculated potential heads are too low, the soil does not retain enough water and the K-values may have to be set more impermeable.

  1. In addition, there are of course other parameters that can also be changed in certain areas:

- increase or reduce the leakage connection of the receiving waters

- Check marginal inflows

- Smoothing the K-values via Attributes Compute Smoothing…: Select KWER and set the weighting factor to, for example, 0.5. This compensates for jumps in the neighbouring mesh elements.

 

After changing the parameters (tip: you should not change too many parameters at once! Always try to change a single parameter and then measure/observe the effect of that single change.), the model must be checked and then a flow calculation can be performed. Then start again at step 4 of the schematic procedure. This procedure is repeated until sufficiently accurate deviations are obtained and the course of the isolines appears plausible.