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Dear all,

I am modelling an schematic estuary with two open boundaries. A constant discharge is prescribed at the river boundary and a tide is prescribed at the sea boundary. To keep it simple, I am modelling suspended sediments transport only, with no erosion.

I am facing a problem to prescribe the suspended sediment at the river boundary. After checking the results, it seems that there is no inflow of sediments at the river boundary. I saw similar posts related to the prescription of suspended sediments at open boundaries. I followed the suggestions but still no inflow of sediments. Maybe there is something wrong in the setup.

I am attaching the setup of my test case





Any help or suggestion will be appreciated.
Regards,
Marcelo

Hello,

Sorry for the late answer.
I think it is because you have 4 (instead of 5) in the TRACER columns of your CONLIM file (the one for SISYPHE. You have it correct in the TELEMAC CONLIM file though.

Try to change that and let us know.

Hope this helps,
Sébastien.

Hi, dear all telemac users.
I have a question about sediment concentation.
I want to set concentration value for each sediment classes.
but if I set it using liquid boundary file for sisyphe,
it seems like that it just set same value for each sediment classes.

For example,

<liquid boundary file>
T CG(1)
0 0.2
86400 0.2

And sediment classes are
0.001 0.0008

It gives CONC MAS CL1 as 0.2
and CONC MAS CL2 as 0.2

and I think total concentration is 0.4

so.. If I want to set total concentration as 0.2,
should I set CG(1) as 0.1?

Please help me and thank you for your attention.
Sincerely.

Yes, as far as I know it is not possible to impose in the liquid boundary file the time-dependent concentrations for different sediment classes.

You can use the conlit.f subroutine to prescribe the time-dependent sediment concentrations. Have a look at the end of the subroutine.
Or if you can prescribe the respective concentrations based on the the total concentration, than you can use still the liquid bounfary file and at the end of the subroutine you can specify for example:
CBOR%ADR(1)%P%R(K)=0.60D0 * CGL(IFRLIQ,AT)/XMVS
CBOR%ADR(2)%P%R(K)=0.40D0 * CGL(IFRLIQ,AT)/XMVS


Hope this helps,
Clemens

Dear Clemens,

If we want to add the time-dependent suspended sediment, is it also modified the file of conlit.f

or the sisyphe has other fortran file to modified ??

I mean for example, In the river, we had to consider both tiem-dependent bedload and suspended load. I know, we could set the bedload in conlit.f


For the total load (bedload, suspened load) is also set in conlit.f or not ?

or we treat the total load as a whole set in conlit.f ?



Best Regards

Yao

Yes,

this should work also. Either you prescribe the bed load and the suspended load infow separately in the conlit.f subroutine or if you want to use a total load formula you should switch off the suspended load transport (it is by default switched off) and you prescribe bed load inflow.
However I didn't never try this but there should be no reason why it shouldn't work.

Best regards,
Clemens

Dear Clemens

Thanks for your answer, I also think it should work.

Regards

Yao

Dear All,

I am interesting in Marcelo's test model so I have done some modification about this Estuary model to introduce only suspension sediment into this domain.

There two open boundaries. Water level data is introduced to the seaward boundary without sediment input. Another boundary is the river boundary with constant discarge and with sediment of 'EQUILIBRIUM INFLOW CONCENTRATION'.

The problem is the hydrodynamics looks fine but the sediment come from the seaward boundary rather than the river, which I cannot understand.

I have attached the model. Any suggestion would be welcome, Many thanks.

Regards,
Bin

You bedlevels are uniformly -10m and the river is over 500m wide, so the inflow velocity due to the 500m3/s discharge is going to be less than 0.1m/s. However, the tidal range is about 3m, so the flow velocities at the sea boundary are going to be much higher. Consequently the sediment influx at the seaward boundary will dwarf those from the river. Try using a flat sea level and sea what the sediment fluxes do then.