Can someone explain the Gas Turbine Vessel engines ?

[Cruise Gopher]

So I understand the Radiance of the Seas is a GTV ship. What I don't understand is how is this different from other ships? What are the advantages and disadvantages of the GTV?

 

Thanks!

[johnjen]

Combustion turbines are basically jet engines. They are more efficient than the older methods of propulsion (steam turbines driven by oil). The jet engine revolves much faster, too. The smaller, the faster they rotate and they are more thermally efficient.

 

I had heard that the US Navy's spruance class destroyers were using DC-10 type engines - I can't confirm that though.

[Cruise Gopher]

Wow cool. So are there even propellers on the ship then? or is it just big water jets underneath?

[wraithe]

Johnjen is correct about the fact that a gas turbine is essentially a jet engine, doesn't matter if it's pure jet, turbofan, turboprop, or marine gas turbine, they use turbine blades to convert heat energy from combustion to electrical energy to drive the ship, and supply electricity.

 

Advantages: quieter, less vibration, less weight for the same power output, lower emissions

 

Disadvantages: typically not nearly the fuel efficiency of the large, low speed marine diesels that are currently being produced, the fuel costs much more than heavy fuel oil for diesels

 

I don't know for sure, but I would imagine that the turbines are connected to generators just like the diesels, the ships are electrically driven, Mariner's generators put out 11,000 volts, and significant current. When I got to tour the control room, the three drives were consuming almost 4 megawatts of power.

 

http://alaska.nwcruiseship.org/article.cfm?menuId=28&articleId=101, wow, check out this link, turns out that there are two turbo-electric generators on Radiance that produce 11,000 volts a piece, then the exhaust gas from the turbines is used to produce steam for another generator. It's a combined process that helps to recover otherwise wasted energy from the exhaust.

 

Thanks for asking the question, I know a lot more about the Radiance class engine rooms now from the research. If I can help anymore, let me know.

[wraithe]

Wow cool. So are there even propellers on the ship then? or is it just big water jets underneath?

 

Yep, two azipods, basically big electric motors with a screw attached, drive the ship powered by electricity from the turbo-generators

[gratefulguy]

BTW,

1. Did I read that RCI is suing Rolls Royce and another co. because the technology didn't work as well as planned--one of the reasons Radiance was in dry-dock was to repair something to do with the ""pods"?

2. Was it trouble with this same system, caused by hitting a reef or bar, etc., that caused QMII to limp around with less than full power or mobility?

I didn't read all the details at the time because I didn't realize I would be on a ship of this type in the near future!

Thanks for any info.

[wraithe]

BTW,

1. Did I read that RCI is suing Rolls Royce and another co. because the technology didn't work as well as planned--one of the reasons Radiance was in dry-dock was to repair something to do with the ""pods"?

2. Was it trouble with this same system, caused by hitting a reef or bar, etc., that caused QMII to limp around with less than full power or mobility?

I didn't read all the details at the time because I didn't realize I would be on a ship of this type in the near future!

Thanks for any info.

 

The lawsuit was sort of RCL, Celebrity filed suit against RR and Alstom Power Conversion Pods for failed Mermaid pods under Millenium and 3 other Celebrity ships. Here's a link to an article:

http://cruises.about.com/library/news/blnews030807a.htm. Although the QM2 had the Mermaid pods, the damage it suffered was due to sideswiping a channel wall and damaging the propellor according to this article: http://www.marinelink.com/Story/ShowStory.aspx?StoryID=201646. The Vision class, Radiance class, Voyage class and Freedom class all use electric drives, so I wouldn't worry too much about the drive systems on RCL fleet ships.

[johnjen]

Wraithe, thanks for posting some info here. Although I was a Radioman/Info systems tech in the nav, I loved being in the pit learning about the turbines and the plant.

 

I am in the middle of reading a really good book called "Rig Ship for Ultra Quiet" by Andrew Karam. As a bubblehead, you would appreciate this one. The author was a nuke machinists' mate on a fast attack boat.

 

I also would recommend "Rising Tide" by Gary Weir, the story of the Soviet submarine fleet.

 

...and for anyone else out there, a really good movie called K-19 with Harrison Ford - a good naval engineering story that tells the truth on what engineering nightmares the Soviets faced in their nuclear submarines.

[wraithe]

Wraithe, thanks for posting some info here. Although I was a Radioman/Info systems tech in the nav, I loved being in the pit learning about the turbines and the plant.

 

I am in the middle of reading a really good book called "Rig Ship for Ultra Quiet" by Andrew Karam. As a bubblehead, you would appreciate this one. The author was a nuke machinists' mate on a fast attack boat.

 

I also would recommend "Rising Tide" by Gary Weir, the story of the Soviet submarine fleet.

 

...and for anyone else out there, a really good movie called K-19 with Harrison Ford - a good naval engineering story that tells the truth on what engineering nightmares the Soviets faced in their nuclear submarines.

 

Haven't heard about "Rig Ship For Ultra Quiet", but I'll check it out. You're right about "Rising Tide" and "K-19, the Widow Maker". Both good books that help to explain what a government that looks at people as chattel is like. The US spent much money shielding our plants, I probably got less radiation while operating submarine nuke plants than most people living on a mountain or in a big city got from the rocks and concrete. The Soviets just burnt their people out, shielding wasn't important. Another good book written by another nuke is "The Complete Idiots Guide to Submarines". You'd be amazed how much it will explain to a layman about subs.

[BobBeaSea]

For RCI I think only the Radiance class ships have this type of engine. It was a topic of discussion at the "meet the capatain" and other officers session. In short the engines are powerful, they burn a different type of fuel and they operate cleanly and quietly. The level of engine efficiency is much higher than traditional engines. Due to the world oil situation, the captain and chief engineer of the Radiance do not believe this type of engine will be installed in any other ships...too expensive for the engine and, more importantly, the fuel.

[wraithe]

Like I said above, you're right about the power in comparison to the weight, and the emissions, they are much lower due to the fact that it uses a different fuel. The article I linked to above, states that the fuel is about 3 times more costly than heavy fuel oil. I have to argue with you about fuel efficiency, turbines are not nearly as fuel efficient as the large, slow operating diesels. They are hitting BSFC's of .9 now, and with the waste exhaust heat used to evaporate sea water to make fresh water, it increases fuel efficiency even more for the diesels.

[English Jane]

My husband works for for Alstom Power in the UK (designing steam turbines for power stations). We hadn't heard about that lawsuit - that must be why we can't get any discount!:D

 

Jane

x

[rolloman]

Is it just a matter of time before we have a cruise ship with total nuclear power? I have to believe with the fuel situation something has to give soon or their will be no more affordable cruising.

[wraithe]

Is it just a matter of time before we have a cruise ship with total nuclear power? I have to believe with the fuel situation something has to give soon or their will be no more affordable cruising.

 

The NS Savannah was the first (and only) US built nuclear powered cruise and cargo ship, it was designed for both. A combination of problems with the engineering and ships unions, which idled the ship several times, as well as the paranoia of anti-nuclear hysteria which prevented the ship from entering some ports. It was designed in the mid '50s with the ship floating out in '59. It operated until 1971 before she was defueled and laid up. I toured her in 1989 while she was still at Patriot's Point in Charleston, SC as part of a museum consisting of several ships. She languishes now in the ghost fleet in the James River in Virginia. There was a civilian nuke power program in the UK, and the USSR, but I don't know if the UK program ever actually built a ship. The USSR program produced many of the same problems as their sub and surface warship fleet, radioactive spills, excessive radiation for the crew, and general poor designs. http://www.radiationworks.com/NSSavannah.htm is a link to an article about Savannah, and with links to an article about the German and Russian civilian cargo ships.

[BobBeaSea]

Like I said above, you're right about the power in comparison to the weight, and the emissions, they are much lower due to the fact that it uses a different fuel. The article I linked to above, states that the fuel is about 3 times more costly than heavy fuel oil. I have to argue with you about fuel efficiency, turbines are not nearly as fuel efficient as the large, slow operating diesels. They are hitting BSFC's of .9 now, and with the waste exhaust heat used to evaporate sea water to make fresh water, it increases fuel efficiency even more for the diesels.

 

The captain and engineer were referring to the efficiency of the engine itself, not about a comparison in fuel efficiency.

[wraithe]

The captain and engineer were referring to the efficiency of the engine itself, not about a comparison in fuel efficiency.

 

Oh, now I understand, that makes perfect sense.

 

 

Jane, that lawsuit was filed in 2003, it's probably long over with now, I would imagine that they settled at some point. Maybe you ought to check into that discount again! :D

[gratefulguy]

I believe they did settle with Alstom, but think Rolls had not yet decided.

[BobBeaSea]

The "nuclear" cruise ship question came up in the session with the captain and chief engineer on Radiance....their answer was an emphatic NO to the possibility of nuclear cruise ships. They went on to explain why this won't happen and they discussed plenty of reasons. :)

[wraithe]

The "nuclear" cruise ship question came up in the session with the captain and chief engineer on Radiance....their answer was an emphatic NO to the possibility of nuclear cruise ships. They went on to explain why this won't happen and they discussed plenty of reasons. :)

 

Wow, I was surprised someone mentioned it here on the boards, much less on a ship itself, but I agree that it won't happen for many, many years. Perhaps one day when we develope direct conversion technology to produce electricity somehow directly from fission. Who knows? Most people have no clue that there are numerous nuclear power plants operating in the oceans at any given time, they just have the standard knee jerk reaction against nuke power.

[rolloman]

Well most of our US aircraft carriers are nuclear powered and I have not heard of a spill killing any sailors. If its safe enough to have these plants all over our backyards and the president advocating more be built, then I want to know some other reasons not to build a cruise ship powered by this technology. I say in about 15 to 20 years cruising will not be affordable as fuel will not be available.

[ORANGEinINDY]

BTW,

1. Did I read that RCI is suing Rolls Royce and another co. because the technology didn't work as well as planned--one of the reasons Radiance was in dry-dock was to repair something to do with the ""pods"?

.

:eek: Were they required to file suit in Miami?:eek:

[wraithe]

Well most of our US aircraft carriers are nuclear powered and I have not heard of a spill killing any sailors. If its safe enough to have these plants all over our backyards and the president advocating more be built, then I want to know some other reasons not to build a cruise ship powered by this technology. I say in about 15 to 20 years cruising will not be affordable as fuel will not be available.

 

There's no reason that it couldn't be built other than cost and perception. Nuclear power is extremely expensive and corners tend to get cut when there is a profit motive involved. It's not as bad now that there are modular techniques of building nuke power plants. The current plants are good for the life of the ship, but that is highly enriched fuel used for Navy ships. Low enrichment fuel like used for the Savannah would most likely need a refueling capability which would have to be overseen by someone, and then who would trust another country to do that with a ship that's entering their harbors? There are many ports in the world that won't allow nuclear powered ships to enter their harbors. When my ship pulled in to Bermuda, we couldn't pull up to the pier, we had to anchor out in the harbor and steam. So that port call was holiday routine, holiday forward, routine aft. There are many other technologies that could be used instead of nuke power with much lower up front costs or regulatory issues, such as renewable fuels, biodiesel, for instance. Hmmm, that would be tough, the ships would travel around smelling like french fries for miles behind them :D , and if a fuel spill occurred, provided it was pure biodiesel, who cares, you can drink it, and it won't hurt you.

[BobBeaSea]

Well most of our US aircraft carriers are nuclear powered and I have not heard of a spill killing any sailors. If its safe enough to have these plants all over our backyards and the president advocating more be built, then I want to know some other reasons not to build a cruise ship powered by this technology. I say in about 15 to 20 years cruising will not be affordable as fuel will not be available.

 

Exactly! And if there is no fuel for ships, how are the passengers expected to get to the ship? They won't be able to afford the fuel to get to the ports. :)

 

The U.S. has a fleet of nuclear powered ships amd boats (subs). Having a nuclear power plant on a warship where security is tight as a drum and ships' personnel have agreed to the risk (by virtue of enlisting) is a far cry from nuclear powered cruise ships...as the captain of Radiance stated, it is not going to happen, period.

[rolloman]

I live within walking distance to the port :-)

 

And as far as the Radiance Captain goes... blah blah blah, Orville and Wilbur Wright were idiots too.

[BobBeaSea]

I live within walking distance to the port :-)

 

And as far as the Radiance Captain goes... blah blah blah, Orville and Wilbur Wright were idiots too.

 

Actually most people in America, the military included, thought the Wrights were crazy. It was only after selling the concept of flight for military purposes in Europe that the American military caught on, after constantly rejecting the Wrights...this was years after Kitty Hawk. You just never know...:)