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Specialty Chemistry Forums => Chemical Engineering Forum => Topic started by: engchess on May 31, 2006, 06:55:57 AM

Title: couette flow plz help
Post by: engchess on May 31, 2006, 06:55:57 AM
hiiii everyone ... i wish u can help me in this .. i have a mass transport project and it is about couette flow .. in the cylinder i have two fluid water and oil .. my dr. ask me a aquetstion to look after it he says why the water rotates around the oil why not the oppisite he give me a hint he says it is to minimize the energy but he want the princibple that states that ? .. can u help me do u have any idea about what principle he is talking about !
Title: Re: couette flow plz help
Post by: Borek on May 31, 2006, 07:41:23 AM
When water and oil separates - which one is at the bottom and why?
Title: Re: couette flow plz help
Post by: engchess on May 31, 2006, 11:36:57 AM
when they are seperates i do not know , but he wants why when they are rotating in the cylinder the oil centerized the water
Title: Re: couette flow plz help
Post by: Borek on May 31, 2006, 11:39:59 AM
Reason is the same, just forces different. Think it over.
Title: Re: couette flow plz help
Post by: Donaldson Tan on May 31, 2006, 12:12:38 PM
Compare their density. Which is "lighter"?

Where does the "lighter" component go?
Title: Re: couette flow plz help
Post by: engchess on May 31, 2006, 12:17:03 PM
yeah i said the density thing ,but he said that beside this there is another reason about minimizing their energy and he wants the name of the principle that says so ..
Title: Re: couette flow plz help
Post by: eugenedakin on June 04, 2006, 12:49:23 AM
Hi engchess,

There is a part of Canada which produces oil which has a higher density than water (Oil density = 1.09, salt-water density = 1.01).  In this case the oil would be at the bottom.  I believe that almost all refined or natural oils have a density near or below 1.0. 

If I said all oils have a density below 1.0, someone would know of a exception-to-the-rule.

 ;)

Best of luck,

Eugene