# [Getdp] Re-4: two disjoined bodies / disjunct

mkoch at gvtc.com mkoch at gvtc.com
Wed Apr 12 15:13:55 CEST 2006

```Hi Matthias,

well, that is exactly one of my concerns, hence the subject title contains the
word "disjoined", and that also is why I liked your thought about
treating this
like a network. (I was able to solve hole problems in the past, though).

However, I know not which one is true, and I simply lack the time and
direction
to explore both of them. The very least I hope to get out of this e-mail train
is for someone to say yes/no, disjoined bodies are impossible, and/or to say,
yes/no treating this like a network is the way to go.

Whichever direction is recommended, I will then also need better pointers than
available in the manual on how to implement the respective strategy. My files
are a feeble attempt at a start, but they probably are completely wrong, so an

Also, the actual motivator for this, i.e. the desire to treat radiation
exchange
problems, only makes sense if we can treat disjoined bodies. The point is that
radiation exchange between two surface is very well known, so we can spare the
computation of the space in between.

Regards,

Matt Koch
978-726-4202
www.scitex.us

----- Message from m.fenner at omicron.de ---------
Date: 12 Apr 2006 07:56:13 UT
From: m.fenner at omicron.de
Subject: Re-4: two disjoined bodies / disjunct
To: mattkoch at alum.mit.edu

> Dear Matt,
>
> after taking a first glance at the files:
>
> Could it be that getDP (or FEM in general) has solutions only on a
> connected Domain? It needs not to be simply connected in a
> "mathematical sense" - at least for heat conduction problems - as I
> have tried on geometries including holes.
>
> Your geometry consists of only two regions which are disjoint sets of
> points. I browsed Christophe's thesis for connected domains. In
> section 1.2 he summarizes the assumptions. I am not sure though if
> this paragraph definitely excludes not connected domains. What do you
> think?
>
> Best regards
>
>
> Matthias
>
>
> Omicron
> NanoTechnology GmbH
>
> Limburger Straße 75
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>
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>
> To: mattkoch at alum.mit.edu
> Cc: getDP at geuz.org
>
>

----- End message from m.fenner at omicron.de -----

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