model blows up when using bulk forcing..

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mashinde
Posts: 135
Joined: Mon Jun 22, 2009 3:46 pm
Location: Indian Institute of Tropical Meteorology, Pune, INDIA

model blows up when using bulk forcing..

#1 Unread post by mashinde »

Hi,

Model blows up at day 344, when I use bulk forcing. I use ROMS 3.4
I attached here log file.

Thanks
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rmed16_etp1_gls.log
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mathieu
Posts: 74
Joined: Fri Sep 17, 2004 2:22 pm
Location: Institut Rudjer Boskovic

Re: model blows up when using bulk forcing..

#2 Unread post by mathieu »

What makes you think bulk forcing is responsible?
There are many other things that could create the
blow-up: horizontal pressure gradient (here you have
relatively large rx1=10), NaN or inconsistent forcing,
too high speed (you have automatic blow at 20m/s), etc.

You give too few information for us to help.
Bulk forcing is usually a very stable component of
the runs. I would advise you to put many output
(like Hout(idUsms)=T, Hout(idVsms)=T
to get the surface stress, if you think the bulk
forcing is responsible) and try to see what really
happened.

mashinde
Posts: 135
Joined: Mon Jun 22, 2009 3:46 pm
Location: Indian Institute of Tropical Meteorology, Pune, INDIA

Re: model blows up when using bulk forcing..

#3 Unread post by mashinde »

Dear Mathieu,

Thanks for the reply. I use GRID_LaplacianSelectSmooth_rx0 of LP bathy to smooth the bathymetry. How can I compute Horizontal Pressure Gradient term ?

-Mahesh

mathieu
Posts: 74
Joined: Fri Sep 17, 2004 2:22 pm
Location: Institut Rudjer Boskovic

Re: model blows up when using bulk forcing..

#4 Unread post by mathieu »

use DIAGNOSTICS_UV and then select the right Dout.
But it is possible that the bathymetry is not the problem.
You need to look at what happened at the time steps before
the blow up. Another idea is to simplify the problem by
removing some feature of your setting, this can help in
some cases.

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susonic
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Re: model blows up when using bulk forcing..

#5 Unread post by susonic »

Did you fix the problem?

I've just noticed that there is no boundary condition for M3 in your application.

I would recommend you to check out the current right before the model blow up.

Cheers,

-JH
Joonho Lee

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