That’s an eye candy! Great developments for greener environment. Just a transition from mc to me resulted in high fuel savings, this would be an icing on the cake.
It looks like the fairwater added to the propeller hub extends to the rudder. It appears however, that if the rudder is at any position other than zero degrees, the stream of water will be exposed to the blunt surface at the junction between the end of the propeller hub and the start of the fairing on the rudder. Is it possible for you to explain this? It could be that I am looking at the video wrong. 20% improvement is incredible.
Hello' i want to ask, is possible reduce a bit more the fuel consumption using 35% of the power of the engine, but connected to a gearbox to not reduce so much the propeller speed?
Dear Spotav, If we understand your question correctly you suggest inserting a gearbox in the propulsion drive train in order to increase propeller speed at low engine power. A rule of thumb in propeller design is that: “The slower a propeller is rotating, the fewer blades and the larger diameter it has the higher efficiency you can have”. There are of course limits inflicting on the rule of thumb and how efficient a propeller you can have. Very often these limits are determined by the maximum allowable propeller diameter on the specific installation and the engine. As propeller and engine are closely connected the highest efficiency is achieved with a holistic view of the propeller system. The optimal achievable efficiency will be influenced both by the propeller installation and the engine optimization. Due to the above the answer to your questions is that it is most likely that you will not benefit from increasing the propeller speed at low engine load but it all depends on the characteristics of the specific propulsion plant in question. Feel free to contact your local MAN Diesel & Turbo office for a more detailed review of your propulsion system.
I don't know how I got here, but I am glad I did. Looks good, sounds good. Good for the environment and for the pocketbook! :) One question: what is that cone in front of the propeller ?
Dear Ninjatriks, There several reasons for having 4 bladed propellers. - Designing propellers is always a compromise between many influencing factors. The optimum number of blades differ from the applications they are used for. There are many aspects such as the trust/power required to reach desired speeds, maximum diameter of the propeller, acceptable levels of cavitation & noise just to mention a few. For many merchant vessels 3, 4, 5 or 6 bladed propellers are the most optimum solutions and for these chemical tankers a 4-bladed propeller will actually result in the highest possible propulsion efficiency. - As this was a retrofit on existing 4-bladed controllable pitch propellers only the propeller blades where exchanged (along with other upgrades of the vessel). The existing propeller hub was reused whereas the number of blades had to remain unchanged. - On submarine the requirements to the propeller are quite different compared to merchant vessels. Stealth is perhaps the most important feature of a submarine and therefore cavitation and noise is to be limited to an absolute minimum in order for the submarine to succeed in its operations. Therefore propellers with 8 or even higher numbers of blades are used.
20% improvement! That's substantial! Amazing technology.
Met one of your employees at CMA 2019. Very nice fellow named Niels who explained a lot about combustion and engine vibration issues.
Great, an Odfjell chemical tanker! Proud to be a co-owner of this company.
That’s an eye candy! Great developments for greener environment. Just a transition from mc to me resulted in high fuel savings, this would be an icing on the cake.
It looks like the fairwater added to the propeller hub extends to the rudder. It appears however, that if the rudder is at any position other than zero degrees, the stream of water will be exposed to the blunt surface at the junction between the end of the propeller hub and the start of the fairing on the rudder. Is it possible for you to explain this? It could be that I am looking at the video wrong.
20% improvement is incredible.
Hello' i want to ask, is possible reduce a bit more the fuel consumption using 35% of the power of the engine, but connected to a gearbox to not reduce so much the propeller speed?
Dear Spotav,
If we understand your question correctly you suggest inserting a gearbox in the propulsion drive train in order to increase propeller speed at low engine power.
A rule of thumb in propeller design is that:
“The slower a propeller is rotating, the fewer blades and the larger diameter it has the higher efficiency you can have”.
There are of course limits inflicting on the rule of thumb and how efficient a propeller you can have. Very often these limits are determined by the maximum allowable propeller diameter on the specific installation and the engine.
As propeller and engine are closely connected the highest efficiency is achieved with a holistic view of the propeller system. The optimal achievable efficiency will be influenced both by the propeller installation and the engine optimization.
Due to the above the answer to your questions is that it is most likely that you will not benefit from increasing the propeller speed at low engine load but it all depends on the characteristics of the specific propulsion plant in question.
Feel free to contact your local MAN Diesel & Turbo office for a more detailed review of your propulsion system.
Thanks
I don't know how I got here, but I am glad I did. Looks good, sounds good. Good for the environment and for the pocketbook! :)
One question: what is that cone in front of the propeller ?
In front of the propeller you see a ‘Wake Equalizing Duct’
Why yes, I do need one of those propellor models for my coffee table.
Would you not loose any gain in efficiency,do to gearbox loss.
Hi
why not Kappels 8 blade, as developed for submarines?
less cavitation/noise less waste of power?
Dear Ninjatriks,
There several reasons for having 4 bladed propellers.
- Designing propellers is always a compromise between many influencing factors. The optimum number of blades differ from the applications they are used for. There are many aspects such as the trust/power required to reach desired speeds, maximum diameter of the propeller, acceptable levels of cavitation & noise just to mention a few. For many merchant vessels 3, 4, 5 or 6 bladed propellers are the most optimum solutions and for these chemical tankers a 4-bladed propeller will actually result in the highest possible propulsion efficiency.
- As this was a retrofit on existing 4-bladed controllable pitch propellers only the propeller blades where exchanged (along with other upgrades of the vessel). The existing propeller hub was reused whereas the number of blades had to remain unchanged.
- On submarine the requirements to the propeller are quite different compared to merchant vessels. Stealth is perhaps the most important feature of a submarine and therefore cavitation and noise is to be limited to an absolute minimum in order for the submarine to succeed in its operations. Therefore propellers with 8 or even higher numbers of blades are used.
Just make a bigger barometer and it's turned a turbine so we got electricity through out the year
Energy problems solved for millions of years
Not enough real information, just puff.
CANT REVEAL ALL SECRETS, AS SUCH MOBILE PHONE ADVERTISEMENTS DONT REAVEAL INSIDE THINGS
باعث افتخاری هموطن منم ۴۶۰ تگا دارم خیلی راضیم
It all started out great...... and then Qatar was involved . . . .
A lot of IP here, no doubt the CCP has the whole lot by now, free of charge.
Waterjet