CSTMS SEDTOY

SED_TOY Test Case

Brief Description of Model Test Case.

Domain

Brief Description of Model Grid.

This 1D model utilizes multiple sediment classes to illustrate sediment distribution and concentration during steady-state conditions, with 21 timesteps. In this test run of Sed_Toy, two cohesive sediment grain size classes are input into the model (0.01mm and 0.005mm). The .01mm sediment class begins on/within the sediment bed at the start of the model; whereas the .005mm grains are found only in the water column. As the model progresses sediment grains settle and/or become suspended, thereby ending with a mixed grained sediment bed at the end of the model run. Sediment concentration profiles can be extracted throughout the time frame for model result comparisons.

Model Parameter	Variable	Value
Length (east-west)	1/Pm	10
Width (north-south)	1/Pn	10

Bottom Sediment

Size	MUD_SD50	0.01 mm	0.005mm
Density	MUD_SRHO	2650 kg/m3	2400 kg/m3
Settling Velocity	MUD_WSED	0.1 mm/s	0.01 mm/s
Critical Shear Stress (Erosion)	MUD_TAU_CE	0.01 N/m2	0.01 N/m2
Critical Shear Stress (Deposition)	MUD_TAU_CD	0.1 N/m2	0.1 N/m2
Init Bed Thickness	bed_thick	0.01 mm	0.01 mm
Init Susp Concentraion	MUD_CSED	0 kg/m3	10 kg/m3
Erosion Rate	E0	5e-5 kg/m2/s	5e-5 kg/m2/s
Porosity	MUD_POROS	0.3	0.3

Forcing

No Coriolis
No heating/cooling
No waves
Winds: A constant surface stress of .0001 m^2/s^2 is applied for time less than 3000 seconds. Surface stress is specified in ROMS/Functionals/ana_smflux.h.

Body Force: Here the surface stress and bottom stress are applied to the water column as a bodyforce. Specifically, input parameter LEVSFRC in roms_sed_toy.in is the deepest level to which surface momentum stress is applied as a body force. LEVBFRC is the shallowest level to which the bottom momentum stress is applied as a body force. In the Sed_Toy test case, LEVSFRC = 15 and LEVBFRC=1.

Steady State Conditions

$${\begin{aligned}\color {Blue}{u}&~=~XXX~m/s^{2}\\\color {Blue}{v}&~=~XXX~m/s^{2}\end{aligned}}$$

Describe steady state sediment concentration and sediment bed

Boundary Conditions

Both the East/West and North/South use periodic boundary conditions.

Physical Constants

Gravitational acceleration ${\color {blue}{g}}~=~9.81~^{2}$
Von Karman's constant ${\color {blue}{\kappa }}~=~0.41$
Dynamic viscosity (and minimum diffusivity) ${\color {blue}{\nu }}~=1e-6m^{2}/s$

Note: If a model incorporates physical constants that differ from these, and/or automatically calculates some values specified here, please specify the values used.

Results

Describe model output that the user should expect to see here. Include one or two figures.