Bed shear stress

Computation of bed shear stress due to current and waves current-related stress is computed following a drag-coefficient approach wave-related stress is computed following Van Rijn approach Combined wave-current mean and max stresses are computed following Soulsby(1995) approach https://odnature.naturalsciences.be/coherens/manual#manual https://odnature.naturalsciences.be/downloads/coherens/documentation/chapter7.pdf#nameddest=Bed_shear_stresses

http://www.coastalwiki.org/wiki/Shallow-water_wave_theory# http://www.coastalwiki.org/wiki/Shallow-water_wave_theory#Seabed_Friction General relationships obtained from : https://repository.tudelft.nl/islandora/object/uuid%3Aea12eb20-aee3-4f58-99fb-ebc216e98879 Description of TRANSPOR2004 and Implementation in Delft3D-ONLINE Take from the work of Simon Wepp in Opendrift

Parameters

spdstr

Name of the column from which to get current speed.

drr: str, optional

Column name representing the current direction.

hsstr, optional

Column name representing the wave height.

tpstr, optional

Column name representing the wave period.

dpm: str, optional

Column name representing the wave direction.

water_depth: str, optional

Column name representing the water depth.

args: dict

Dictionnary with the folowing keys: water_depth: float

Total water depth or level from which the current was taken

mode: str

Use 3D or 2D for 3D current or depth=average current. default 2D

rho_water float:

Sea water density kg/m3, default 1027

z0 float:

Roughness height, default 0.001

inlude_current str:

True or False if calculating the shear stress from current speed

inlude_wave str:

True or False if calculating the shear stress from wave

wave_friction str:

Soulsby or Swart formulae, default Swart

Examples:

>>> df=tf['test1']['dataframe'].DataTransformation.bed_shear_stress(spd='spd',hs='hs',tp='tp',args={'water_depth':10})
>>>