Harmony of the Seas claim

"Harmony of the Seas will produce 20% less CO2 emissions than the two largest ships in its class, partly thanks to air pumped into the hull to lighten its load." http://www.theguardian.com/travel/2...orlds-largest-cruise-ship-harmony-of-the-seas



Apparently air is pumped out of the hull to form bubbles which is claimed to reduce drag. But the 20% reduction is also attributed to "hydronamic design, a new type of engine and product enhancements".
http://www.royalcaribbeanblog.com/2...-more-details-about-harmony-of-the-seas-media
http://www.royalcaribbeanblog.com/2013/07/25/royal-caribbean-chairman-increased-revenue-efficiency

 

More snake oil salesmanship of those punting air lubrication as the next best thing since sliced bread no doubt

 

Russian supercavitating torpedo's use similar technology, at least in this size it seems to work.

https://www.militaryperiscope.com/mdb-smpl/weapons/minetorp/torpedo/w0004768.shtml

 

More interesting to me was the claim that "air pumped into the hull to lighten its load" increased efficiency. That sounds to me like a writer who knows nothing about how ships float.

 

Maybe he's confusing it with breaking wind? /runsaway

 

One would think that the passengers would use the air for breathing purposes, thus negating the lighter ship absurd claim. (snicker)

Aside from absurd claims about air, this is the ultimate "Mine is bigger than yours" thing.

 

Presumably helpful when she makes contact with an iceberg....

 

• Harmony of the Seas will be 33 centimeters longer than Allure of the Seas, making it the largest cruise ship in the world.

You probably are not very conversant with metrics, but 33 centimeters is way over 12" ! That is monumental when talking about a ship that is more than 1187' in length, it amounts to pretty near .00085% bigger!


The pressurized hull thing is a 3 step process. First, the hull is pressurized and at the same time a life boat drill is declared. When all passengers are at their assigned stations, the initial pressure is explosively relieved which blows most skinny/lightweight/unprepared/poor people overboard resulting in obvious weight reduction. The hull is then re-pressurized, capitalizing on the principle of air being lighter than steel, the more air put into a space, the lighter it will be. It is science.

 

In short, this is a claim of a giant inflatable boat.

 

look at the smoke belching out the stacks!
http://www.theguardian.com/travel/g...-the-seas-cruise-ship-southampton-in-pictures
WTF?

Says its all diesel electric and pods. Don't new big diesels burn cleaner than that?https://en.wikipedia.org/wiki/MS_Harmony_of_the_Seas

 

I saw something about this and they were saying that the bubbles worked like roller bearings between the hull and the water. Remember folks, I'm just repeating what I heard, I have no idea if it will work. Try it at home and let me know.

 

http://www.glmri.org/downloads/2011Reports/affiliatesMtg/Makiharju.pdf

 

If the ship is to float, partially, on air bubbles, then does that not affect the draft of the ship? When the draft increases because the ship is being partially buoyed by air, does the reduced skin friction as a result of the bubbles more than compensate for the additional wetted surface? More than that the machinery that is to generate bubbles from the compressed air for such a humongous ship must be rather impressively big and costly to operate. I call the claim Hogwash.

Although I say nay, I am willing, even anxious, to learn. I defer to Sharpietwo's wise tag line. "I never learned anything from an argument that I won". Meanwhile.....Hogwash.

 

I am highly skeptical of the air-bubbles claim (if that is the claim), to say it in a gentle way.

 

Neither here: http://www.ship-technology.com/projects/harmony-of-the-seas-cruise-ship/
nor here: http://www.royalcaribbean.co.uk/our-ships/harmony-of-the-seas/smart-ship/
nor here: http://www.royalcaribbeanblog.com/2015/09/24/previewing-harmony-of-the-seas-technology
is the air mentioned as a mean for reducing ship's resistance.
I am pretty sure that such an unusual and advanced feature would be widely publicized in every technology website, magazine and publication. But perhaps I am wrong.

P.S.
I have to correct myself.
Found this article: http://www.worldofcruising.co.uk/technology-helps-royal-caribbean-cut-emissions/
and this: http://www.worldofcruising.co.uk/technology-helps-royal-caribbean-cut-emissions/
which do mention the air-bubble technology. I'll try to find out if that info is true. Meanwhile, I remain skeptical.