Learned something new ...Dead water

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Learned something new ...Dead water

#1  Postby Macdoc » Jul 07, 2020 9:31 pm

What makes ships mysteriously slow down or stop, even though engines are running?
Date:
July 6, 2020

What makes ships mysteriously slow down or even stop as they travel, even though their engines are working properly? This was first observed in 1893 and was described experimentally in 1904 without all the secrets of this ''dead water'' being understood. A team has explained this phenomenon for the first time.


https://www.sciencedaily.com/releases/2 ... 152701.htm
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Re: Learned something new ...Dead water

#2  Postby Evolving » Jul 08, 2020 6:48 am

How fascinating. It must have been rather terrifying when it inexplicably happened (was it the angry gods, was it a sea monster holding the ship fast before emerging from the deep to devour everybody on board...).
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Re: Learned something new ...Dead water

#3  Postby felltoearth » Jul 08, 2020 3:14 pm

Laminar flow. It’s a fascinating feature of hydrology. We deal with similar phenomenon in floodplain studies though with opposite effects, highly turbulent flow due to friction caused at the boundaries between layers due to different flow the velocities.
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Re: Learned something new ...Dead water

#4  Postby laklak » Jul 08, 2020 4:05 pm

Fluid dynamics is complicated stuff.
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Re: Learned something new ...Dead water

#5  Postby newolder » Jul 08, 2020 4:19 pm

An unsolved Millennium Prize Problem too: follow Navier-Stokes equation
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Re: Learned something new ...Dead water

#6  Postby campermon » Jul 08, 2020 5:27 pm

laklak wrote:Fluid dynamics is complicated stuff.


It certainly is! I remember it being thirsty work solving fluid dynamics problems when I was a lad at uni.

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Re: Learned something new ...Dead water

#7  Postby Svartalf » Jul 08, 2020 5:48 pm

yeah, I remember finding out that bubbles in Guinness were indeed actually going down because the stout is so thick it makes them sink.
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Re: Learned something new ...Dead water

#8  Postby campermon » Jul 08, 2020 6:00 pm

Svartalf wrote:yeah, I remember finding out that bubbles in Guinness were indeed actually going down because the stout is so thick it makes them sink.


Yes. I still can't get my head round that!

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Re: Learned something new ...Dead water

#9  Postby Papa Smurf » Jul 08, 2020 8:00 pm

Macdoc wrote:
What makes ships mysteriously slow down or stop, even though engines are running?
Date:
July 6, 2020

What makes ships mysteriously slow down or even stop as they travel, even though their engines are working properly? This was first observed in 1893 and was described experimentally in 1904 without all the secrets of this ''dead water'' being understood. A team has explained this phenomenon for the first time.


https://www.sciencedaily.com/releases/2 ... 152701.htm


One gap less...
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Re: Learned something new ...Dead water

#10  Postby Macdoc » Jul 08, 2020 10:10 pm

hehe :thumbup:
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Re: Learned something new ...Dead water

#11  Postby Svartalf » Jul 08, 2020 10:38 pm

Are you folks owner of said gap? If you can't prove ownership satisfactorily I'll have to sue you on behalf of god whom you're blatantly trying to evict by destroying its habitat.
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