MIKE 21/3 Hotfix 03-12-2009

MIKE 21/3 Oil Spill: A large number of changes have been made in the Oil Spill module to correct and improve functionality.

The following issues have been fixed and changed:

• GUI:
  An error caused the GUI not to accept external files to specify sources, time series, etc.
• Engine:
  1) For concentration calculations the still-water depth was used. This has been changed to current total water depth.
  2) Source definitions are now handled in a smarter way. Prior to this hotfix source specifications where applied “per particle”, thus changing the number of particles would change the source flux. Now source items classified as mass or concentration in the model formulations are by default scaled to the number of particles whereas other items (e.g. viscosity) are applied per particle. The old behaviour can be switched on by unselecting a checkbox in the source dialog
• Oil Spill Template:
  1) Water viscosity was wrongly specified as kinematic viscosity [m2/s] instead of dynamic viscosity [Pa s].
  2) A constant was wrongly specified as “grain diameter [mm]” but needs to be given as “average grain radius [m]”, causing deviations in the expected settling speed.
  3) The wax and asphaltene fraction was assumed to have an initial mass of 10kg each. Now the given fractions are used. This may influence the emulsion behaviour. PLEASE NOTE THAT THE FRACTIONS REMAIN CONSTANT DURING SIMULATION, I.E. THE RELEATIVE AMOUNT OF WAX/ASPHALTENE DO NOT CHANGE. THIS WILL PROBABLY BE CHANGED IN FUTURE RELEASES.

Known defect: The GUI probably does not set the right wind type when time and spatial varying wind field components are selected. If you get the error message "Format not supported for PT/OS wind forcing" try to manually edit the setup file (*.noil). Search the section labelled [WIND_FORCING] and replace ”format = 0” with “format = 3”.