[NEMO] Topic #13 - [LIM3] Question about diffusion operator
https://forge.ipsl.jussieu.fr/nemo/discussion/topic/13
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[LIM3] Question about diffusion operator
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https://forge.ipsl.jussieu.fr/nemo/discussion/topic/13
Trac 1.0.1 - DiscussionPluginivano.barlettaWed, 31 May 2017 09:37:14 GMTTopic #13 - [LIM3] Question about diffusion operator
https://forge.ipsl.jussieu.fr/nemo/discussion/topic/13#topic
https://forge.ipsl.jussieu.fr/nemo/discussion/topic/13#topic
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Dear NEMO/LIM developers
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I would like to have some explanation about diffusion operator in LIM3, and the way it is calculated
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I cannot figure out what equations is actually solved in lim_hdf routine.
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the advection/diffusion equation for a generic ice component is something the like ( apart from scale factors and other terms in the equation):
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d X d t = - div ( X . u ) + D laplacian ( X ).
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as far as I understood, first transport is solved, namely
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d X / d t = - div ( X . u )
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leading to a value of X at next time step, X<sup>(n+1)</sup>
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then the diffusion is added,
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X<sup>(n+1) </sup>=X<sup>(n+1)</sup> + D laplacian ( X<sup>(n+1)</sup> )
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where X<sup>(n+1)</sup> Is a known quantity. So I cannot figure out why an iterative method
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is used.
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The question is, what am I missing?
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Thanks Ivano
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TopicnicolasmartinTue, 03 Sep 2019 18:21:59 GMTReply #199 to topic #13 - [LIM3] Question about diffusion operator
https://forge.ipsl.jussieu.fr/nemo/discussion/message/199#message_199
https://forge.ipsl.jussieu.fr/nemo/discussion/message/199#message_199
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Mark subject as resolved without further updates.
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