Steps To Set up a Sediment Bed Model

  1. Enter the Sed/Tox/Others Tab and click on the Modify button in the Sediment and Sediment Bed Settings frame.
  2. Define the number of sediment bed layers, cohesive and non-cohesive sediments as shown in Major Settings of EFDC Sediment Model (it is important do this first to avoid losing data).
  3. Set the options in the General tab for the Primary Computational Options and the Bed Shear Calculation Options.
  4. In Cohesive tab the user should enter the appropriate values for the relative parameters as well as defining the minimum and maximum values of Cohesive Fluids Concentration as shown in Figure 1.
  5. In the Non-Cohesive Suspended Load tab the user should define the Equilibrium Concentration Option and enter the appropriate values for the relative parameters and non-cohesive layers.
  6. In the Non-cohesive Bed Load tab the user should click on Initialize Constants button and enter the number for the approaches desired e.g. enter "1" for the Van Rijn approach.
  7. In the Morphology & Consolidation tab the user should select the Bed Morphology Options: 0-No Bed Change, 1-Allow Bed Changes. The user should also set the Max Layer Thickness and Constant Porosity to be the same values as in the input sediment file (refer to Appendix B - Data Formats for the DSM format of the file).
  8. In the Initial Conditions Tab: select the Sediment Initial Condition Options. There are 2 options to initialize bed layers: Uniform bed and use initial data file.
  9. Initialize the sediment bed from file, browse for the input sediment file
  10. Check Use sediment cores with grain size
  11. Define the maximum grain size for each size class relatively to cohesive and non-cohesive layers as displayed in the in the red frame in Figure 2.

If the required information has been entered then the Apply button is visible. After clicking on Apply, the sediment bed will be initialized.



Figure 1  Sediment Bed Model: Cohesives Tab.


Figure 2  Sediment Bed Model: Initial Conditions Tab.