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Cylinder sails promise up to 90% fuel consumption cut for cargo ships
New Atlas ^ | JULY 31, 2024 | David Szondy

Posted on 08/02/2024 11:16:26 AM PDT by Red Badger

click here to read article


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To: Harpotoo

It says they can be retracted, so I would imagine so.


141 posted on 08/03/2024 9:46:56 AM PDT by Vermont Lt (Don’t vote for anyone over 70 years old. Get rid of the geriatric politicians.)
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To: TexasGator

“It doesn’t work for cargo ships”

Testing on commercial ships show >20% fuel savings with 4 rotors.


142 posted on 08/03/2024 10:36:04 AM PDT by TexasGator
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To: TexasGator

“Your 100 hp is not realistic.”

Thanks for catching that—with respect to “tall ships” sailing equivalent horsepower...

:-/

The number should have been:

ONE HUNDRED THOUSAND horsepower.


143 posted on 08/03/2024 11:43:17 AM PDT by Does so ( 🇺🇦......Say it fast...Kamala D. Harris = KALAMITY Harris...)
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To: TexasGator
LOL   But the effect is the same.   The air jet against the curved surface causes pressure that propels the ship through the water.

I typed, Zha's rotor sucks air in and then blows out its own wind that curves around the rotor.

That is exactly what you just said.   I was agreeing with you.

144 posted on 08/03/2024 3:27:08 PM PDT by higgmeister (In the Shadow of The Big Chicken! )
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To: higgmeister

“That is exactly what you just said. I was agreeing with you.”

Almost. You referenced a “rotor”.

I was clarifying that it doesn’t rotate.


145 posted on 08/03/2024 3:41:32 PM PDT by TexasGator
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To: aquila48
It says clearly in the article that the cylinders don’t spin. It is not based on the Bernoulli (or Magnus) effect.

Yes that's clear, but if you had watched this video that "WhoisAlanGreenspan?" linked to, you would have seen that this professor also showed the effect of air blowing against a static rotor just as “The CoFlow Jet cylinders developed by Zha..."

If you also think a little you would see that Professor Zha was inspired by the studies of the Bernoullis, Magnus, Flettner and all of the others in the interim up until Professor Zha's worked out his new system.   If you read the text at the OP, you see that Professor Zha used the Flettner rotors to explain his new system.

Isaac Newton's most famous statement was, “If I have seen further it is by standing on the shoulders of Giants”.

146 posted on 08/03/2024 3:51:16 PM PDT by higgmeister (In the Shadow of The Big Chicken! )
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To: TexasGator

“And if you had read the article............”

Why?
We had a headline to go by.


147 posted on 08/03/2024 4:01:05 PM PDT by HereInTheHeartland (Have you seen Joe Biden's picture on a milk carton?)
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To: higgmeister

“Yes that’s clear, but if you had watched this video that “WhoisAlanGreenspan?” linked to, you would have seen that this professor also showed the effect of air blowing against a static rotor just as “The CoFlow Jet cylinders developed by Zha...””

Nope. When he blew on the rotor evenly as a wind blows on a CoFlo there was NO effect, i.e., no pressure difference.


148 posted on 08/03/2024 4:03:13 PM PDT by TexasGator
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To: TexasGator
You got me there but in the text it says:
GeCheng Zha, a professor of aerospace engineering and director of the Aerodynamics and Computational Fluid Dynamics Lab at the University of Miami College of Engineering is using an approach that is a variant of the Flettner rotors developed in the 1920s, but with a fundamental twist.
So, in the article it was called a variant of a rotor, but I get your point now.
149 posted on 08/03/2024 4:17:08 PM PDT by higgmeister (In the Shadow of The Big Chicken! )
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To: higgmeister
"The air jet against the curved surface causes pressure that propels the ship through the water."

I have referred to pressure differences but it is actually a change in the flow of the air molecules that drives the force. For every action there is an equal and opposite reaction.


150 posted on 08/03/2024 4:18:08 PM PDT by TexasGator
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To: TexasGator
Wait a minute, when he blew air at the edges of the static rotor cylinder it gave the same effect as Professor Zha's design showing the pressure difference.

I bet you didn't watch the whole video did you?

151 posted on 08/03/2024 4:30:04 PM PDT by higgmeister (In the Shadow of The Big Chicken! )
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To: higgmeister

“Wait a minute, when he blew air at the edges ...”

I guess I have repeat my previous:


When he blew on the rotor evenly as a wind blows on a CoFlo there was NO effect, i.e., no pressure difference.”



152 posted on 08/03/2024 4:40:44 PM PDT by TexasGator
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To: TexasGator

“I bet you didn’t watch the whole video did you?”

Did you miss the part where he blew evenly and there was no effect? It was immediately before where he blew on the “edges”.


153 posted on 08/03/2024 4:43:06 PM PDT by TexasGator
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To: Political Junkie Too

You do of course realize the ship you show is not a container ship but a bulk carrier as is evident by the hatches on the deck to load and unload the bulk cargo...right...right? From the looks of it there would be a few thousand square meters of wind capture area. Humans for 50,000+ years moved across the water by wind power alone. Every corner of this planet had humans carried by water and sails with our cargo in tow.

This group improved on Magnus sails by removing the rotation and using flowing air along the cylinder surface instead. Added benefit is you can reverse the flow.direction and move the injection point in a full 360 range this means you can use the Magnus effect from any wind angle including dead ahead just by changing the angle of the injection air jets. These are lift devices not drag soaks they have a lift coefficient which means they can have 3 to 10 times as much force as a sail of equal sq meters lift is always better than drag.


154 posted on 08/04/2024 2:07:20 AM PDT by GenXPolymath
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To: GenXPolymath
I do now.

-PJ

155 posted on 08/04/2024 4:03:22 AM PDT by Political Junkie Too ( * LAAP = Left-wing Activist Agitprop Press (formerly known as the MSM))
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To: GenXPolymath

“you can use the Magnus effect “

As I understand it, The term “Magnus Effect”. applies to the behavior of a spinning object? While the underlying physics are the same the CoFlo is not spinning.


156 posted on 08/04/2024 9:35:00 AM PDT by TexasGator
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