Open boundaries

[Tiago Silva (Cefas)]

Hi

 

Does GETM have a radiation scheme for open boundaries that takes in 3D velocity fields instead of just depth averaged (as Flather does)?

The aim is to do a nested domain with a one way coupling to a larger 3D domain.

 

Thanks,

tiago

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[Knut]

Hi Tiago,

>
>
>
> Does GETM have a radiation scheme for open boundaries that takes in 3D
> velocity fields instead of just depth averaged (as Flather does)?
>
>

although this is highly desired, unfortunately not yet.
So you are welcomed to start this development :-)

> tiago
>
Knut

[Tiago Silva (Cefas)]

Thanks,

So I am right in assuming that the present implementation of Flather is
the best available scheme for a driving a 3D domain with a (coarser) 3D
model?

Tiago

[Bjarne Büchmann]

You should at least also use the ”outer” model to generate boundary conditions (S,T,...) for the “inner” model, but I assume you already know that.

Flather should then be used for the elevations.

 

 MED VENLIG HILSEN
 
Bjarne Büchmann
 Civilingeniør, PhD

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[Tiago Silva (Cefas)]

Yes, I am using the outer model to provide depth integrated velocities, elevation, temperature and salinity.

 

Thanks,

tiago

[Karsten Bolding]

Hello

On Thu, May 03, 2012 at 12:02:56 +0100, Tiago Silva (Cefas) wrote:
> Yes, I am using the outer model to provide depth integrated velocities, elevation, temperature and salinity.

What do you expect to gain by specifying velocity profiles - instead of
transports? It might actually be that you'll get a more noisy solution
as the discrepancy between boundary conditions and inner solution might
deviate. If you only specify transports (might be wrong enough) you
still allow for a 'freely' developing velocity profile - with a vetical
integral equal to the transport.
>
>
>
> Thanks,
>
> tiago
>

Karsten
>
--
http://www.getm.eu

[Tiago Silva (Cefas)]

Karsten,

I don't have experience with a 3D-3D unidirectional nesting, so I might
be missing out on the disadvantages of prescribing the vertical velocity
profile (the noisy solution you mention). But am I not more likely to
reach the correct solution on the inside by further constraining the
boundary conditions?

tiago

-----Original Message-----
From: getm-...@googlegroups.com [mailto:getm-...@googlegroups.com]
On Behalf Of Karsten Bolding
Sent: 03 May 2012 12:27
To: getm-...@googlegroups.com

[Bjarne Büchmann]

<snip>

 

> But am I not more likely to
> reach the correct solution on the inside by further constraining the
> boundary conditions?

 

No. Probably not.

 

/Bjarne

 

[Tiago Silva (Cefas)]

I am not getting much from you answer but there are methods aimed at dealing with over-specification of OBC in particular regarding to outward fluxes (e.g. Marchesiello et al 2001).

 

Tiago

 

 

 

From: getm-...@googlegroups.com [mailto:getm-...@googlegroups.com] On Behalf Of Bjarne Büchmann

Sent: 07 May 2012 07:25
To: getm-...@googlegroups.com