Tidal Characteristic Numbers of Eff. Bed Shear Stress Action
From BAWiki
A graphic sketch for the definition of the various tidal characteristic numbers of effective bed shear stress action is not available.
Remark: With action the time integral for effective bed shear stress is meant. Integration is typically done for the period of flood current duration as well as for the period of ebb current duration.
Motivation
The calculation as well as the graphic visualization of various tidal characteristic numbers for the action of the effective bed shear stress contributes to an improved understanding of the impact of tidal flow on the bed as well as on bed load sediment transport for areas like coastal seas and estuaries as well.
- As the calculations are performed separately for the durations of ebb- and flood-current it can be shown that the action or impact of the flow on the bed can differ significantly. This can be related to locally varying flood-ebb asymmetries for either ebb and flood current velocities or otherwise differences between flood and ebb current duration.
- The residual action of the effective bed shear stress may be, but needs not to be, consistent with residual bed load sediment transport. Differences may be due to either the non-linear dependence of bed load transport on bed shear stress or otherwise effected by differences in sediment availability.
An automatic analysis of all tidal characteristic numbers of effective bed shear stress action is carried through by the computer program TDKLF.
Definitions for the Tidal Characteristic Numbers of Effective Bed Shear Stress Action
Flood Current
Action of Effective Bed Shear Stress due to Flood Current
time integral of effective bed shear stress over flood current duration
Example: not available.
Ebb Current
Action of Effective Bed Shear Stress due to Ebb Current
time integral of effective bed shear stress over ebb current duration
Example: not available.
Tidal Cycle
Residual Action of the Effective Bed Shear Stress
If the action of effective bed shear stress during flood current duration is equal but in opposite direction of the ebb current related action this will result in a zero residual action of the effective bed shear stress
Example: not available.
Ratio between flood- and ebb-current induced action of the effective bed shear stress
flood to ebb ratio for the respective action of the effective bed shear stress
Example: not available.
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