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djemaa December 30, 2000 06:03

confined jets
 
is the model ka ibsilone the most mode to simulated of confined jets

Ghanshyam Singh December 30, 2000 08:43

Re: confined jets
 
Currently none of the two-equation turbulence model is good for Jets(free or confined). Though it is claimed that Realizable K-epsilon model is good but claim is only by the others. No one else has tested it (as of I know). Any way, your English looks very very bad. You are from?

GS

djemaa December 30, 2000 09:56

Re: confined jets
 
je suis de l'algerie je travaille sur un sujet qui traite un ecoulment d'un jet confine dans une machine aide respiratoire , je veus savoir est ce que on peut consedere le comportement de cette jet au bord de l'ejection comme etant un jet libre

John C. Chien December 30, 2000 13:50

Re: confined jets
 
(1). Even though I had one year French course, I don't think I can read your message. (2). I think, the better approach is to use simple words and symbols to write the message. For example, your question could be written as: Confined Jet, k-E two-equation = best? (3). The answer to the question is : K-E two-equation = all right, but N.E. best. That is, you can start using it, but there are problems related to the results, perhaps higher jet spreading.

Ghanshyam Singh December 30, 2000 13:52

Re: confined jets
 
Excuse me, I can't understand you. If you can write in English we can discuss.

GS

Ghanshyam Singh December 31, 2000 02:16

Re: confined jets"errata"
 
Please read "authors" instead of "others" in the second line of my previous posting. I am sorry for commenting on your English. Mine too is not that good. We write "Hinglish"!!!!! Any way John's idea is good, better begin with k-epsilon model.

GS


Chetan January 2, 2001 05:25

Re: confined jets
 
Here is an attempt at translation.

I am an Algerian and I am working on the subject of flow of confined flows for a respiratory aid equipment. I want to find out if I can consider the jet at the edge of the ejection as free jet.

Chetan

djemaa January 2, 2001 06:35

Re: confined jets
 
avez vous deja utiliser le code de calule Team

Ghanshyam Singh January 2, 2001 07:55

Re: confined jets
 
You have to tell me the aspect ratio, that is the ratio of the diameter(or equivalent diameter)of the confinement to the dia. of the jet. If it is too large then you can assume it as a free jet. Typically, if the aspect ratio is of around 20 or less you cannot assume it as a free jet. Effects of wall will be very much predominant. There is a Non-Dimensional parameter called Craya-Cutret Number. Frequently used to characterize the flow pattern in case of confined jets. I can give you some more details after knowing more exactly about your prob.

GS

djemaa January 2, 2001 09:35

Re: confined jets
 
le rapport des diametre est inferieure a 20 je te presente mon prebleme je travaille sur un sujet qui traite un ecoulement d'un jet confine dans une machine aide respiratoire , j'utilise le code de calcule appelle Team et je trouve beaucoup de preblemes pour sumiller cette ecoulement surtous ce qui conserne pour une chambre de confinement divergente , je souhaite que vous pourez m'aider, j'ai un manque de documentation qui traite ce type d'ecoulement.merci

djemaa January 2, 2001 10:29

Re: confined jets
 
merci


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