Everything Old is new again - Flettner Rotor Ship is launched

Now there's a second commercial rotor ship - Norsepower's rotor sail was installed on Bore's RORO ship "Estraden" & it's undergoing sea trials.





http://www.norsepower.com/rotor-sail-solution/Reference installation
http://worldofwindenergy.com/2014/12/01/norsepower-starts-rotor-sail-sea-trials/


What I wonder about is since the rotor is placed asymmetrically & while providing some forward thrust, won't it be veering the ship off a little?

 

With such a huge superstructure, and they took down a big antennae tower, the bit of drag will hardly be felt.

This seems to be a trial exercise, and was probably heavily subsidised by NorsePower and their partners.

Looking at the boats trip, and prevailing winds, it appears to have good potential provide some useful propulsive effort - no doubt carefully measured for future projects

 

an interview and installation video here (in finnish)
http://www.ts.fi/uutiset/kotimaa/706180/Moderni purje tyontaa rahtilaivaa

roughly what he (the CEO) says:
This is a protorype and relatively modest sized as such. Normally a ship like this would carry 3 or 4 towers.
In ideal conditions 30% reduction in consumption can happen but that is not a number the investment decisions should be based on. In good route and wind conditions 10-20% savings can be reached.
He also mentions that before an investment decision a detailed analysis of wind data on planned route are made.

etc.

 

Thanks for that info, it is very interesting to know.

Yes, it would certainly be standard practice to evaluate the winds, for trips like this. It is so important. Hopefully the results this will whet the interest of other investors.

 

Found some old photos showing an American rotor boat: http://www.lesliejonesphotography.com/taxonomy/term/1313/all

 

I've seen these pics of MIT navy launch but cannot find no information about it...the rotor looks like it could be a smoke stack...anyone have any ideas where to get info on this project ?

 

Anyone able to Translate German ? E-Ship video

Came across this by accident

 

Some project of a coaster with rotors: http://www.youtube.com/watch?v=aQXp75Qt99M


http://www.maritim-de-nl.eu/projekte/wind-hybrid-coaster/

http://www.maritim-de-nl.eu/cms_uploads/files/hansa_redaktion_opt.pdf
http://www.maritim-de-nl.eu/cms_uploads/files/broschüre_whc_final.pdf

 

Some good information on this video - instead of just advertising. The accompanying PDF stress the point that routes with steady winds are needed to achieve the projected 30% fuel savings, and it takes about 4 years to pay for the system.

some examples below

 

Does anyone know a good reference on what the optimal or critical roughness is on a flettner rotor, or whether it matters much? Does it depend on Reynolds number?

 

I dont have the link to hand, but a lot of work has been done on the performance of rotors with rough or dimpled surfaces over he years.

The results have placed smooth surfaces with Thom fences as being the most effective.

Some years ago, a Japanese firm was promoting a continuous helical fence for low speed, hi-torque application.

 

One more design:


http://www.nsrsail.eu/2015/08/13/5000-dwt-flettner-freighter/
http://www.nsrsail.eu/wp-content/uploads/2015/08/Factsheet_FlettnerFreighter.pdf

The E-SHIP 1 at least has it's own cranes, but here unloading a gearless ship with same rotors arrangement would be a challenge!

Also, I don't think this design is cargo efficient: hold dimensions are 62.3x12m but the LBP is 117.38m. Compare that to standard European freighters of 85m LBP with exactly same hold dimensions. And rotors arrangement is taking away some free deck space that could have been used for cargo.
I see on GA plan they placed 2 barrels for LNG in front of the engine, reducing the hold volume even more...

 

Norsepower press release on finished trials.

http://www.norsepower.com/SiteAssets/news/Norsepower Press Release 2015-06-01 EN FI SE.pdf

 

"“The successful trials of our wind technology are a ground-breaking moment not only for Norsepower, and also the wider development of wind pr
opulsion technology for shipping. The results suggest that when orsepower’s technology is implemented at scale, it can produce up to 20% net savings in fuel costs with a payback period of less than four years at current fuel
prices, confirming that wind technologies are commercially-viable solutions that reduce fuel and carbon emissions in the industry,” said Tuomas Riski, C
EO, Norsepower. "

Good news for the only commercial wind assist technology that is currently undergoing trials.

 

Would it not be better just to have a couple of masts and sails. They can be computer and hyd controlled to reduce man power.