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about "the direction of the normal component on interior boundaries"
Posted Jan 30, 2011, 9:30 p.m. EST Parameters, Variables, & Functions Version 4.0 2 Replies
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I see such kind of introduction about the direction of the normal component on interior boundaries:
In ID:
- unx, the outward unit normal seen from the upper domain
- dnx, the out ward unit normal seen from the lower domain
1) What's the meaning of upper/ lower domain? For example, if I draw two domains, domain 1 and domain 2, the upper domain is domain 1 and the lower is domain 2 (judged according to the domain number)?
2) If (1) is correct, what's the meaning of "seen from the upper / lower domain"? For example, "the outward unit normal seen from the upper domain (domain 1)" refers to the outward unit normal pointing out from the lower domain (domain 2) ?
In ID:
- unx, the outward unit normal seen from the upper domain
- dnx, the out ward unit normal seen from the lower domain
1) What's the meaning of upper/ lower domain? For example, if I draw two domains, domain 1 and domain 2, the upper domain is domain 1 and the lower is domain 2 (judged according to the domain number)?
2) If (1) is correct, what's the meaning of "seen from the upper / lower domain"? For example, "the outward unit normal seen from the upper domain (domain 1)" refers to the outward unit normal pointing out from the lower domain (domain 2) ?
2 Replies Last Post Jan 31, 2011, 10:22 a.m. EST
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Posted:
1 decade ago
Hi
I understand it as :
see from current domain: "up" is "outward" of current domain, "down" is "inward",
hence up for one of two ajacent domains is down for the other
--
Good luck
Ivar
I understand it as :
see from current domain: "up" is "outward" of current domain, "down" is "inward",
hence up for one of two ajacent domains is down for the other
--
Good luck
Ivar
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
I understand it as :
see from current domain: "up" is "outward" of current domain, "down" is "inward",
hence up for one of two ajacent domains is down for the other
--
Good luck
Ivar
Hi, thank you!
I see, in the example of freeze-drying of comsol 3.5a, a variable, named Q_s, defined as down(fluxz_ht)*dnz+down(fluxy_ht)*dny+down(fluxx_ht)*dnx
so, if "down" is "inward" of current domain, how did comsol know which domain is current domain?
by the way, it is quite difficult to understand this part just reading the user's guide.