Steam powered boat why not do it again?

[sailorboy1]

Originally Posted by ArtM

The point of making the steam is to drive the turbine to produce the electricity that drives the shafts. Steam is the only method I know of to convert nuclear energy to any other form. I'm not aware of any direct-conversion method to convert nuclear energy directly into electrical or mechanical energy.

If the sub were diesel powered, then no steam would be necessary.

Wait - how are you going to run a diesel engine on a submarine? For that matter, where does oxygen come from on a submarine? I could look it up I guess....

Art are you really trying to say I'm wrong and you are right?

Man where did I put my submarine qualification dolphin pin? Maybe it was a bad dream and all those years I was in a coma or something!

PS - modern nuc subs can run the diesel while submerged, go look that one up!

[ArtM]

I don't know man. Your comments about the use of a diesel engine to produced DC power on a Nuclear powered submarine are boggling my mind. I don't know what to make of it. One of us seems to be "mildly confused".


Also, this is an your answer to your answer of the question of whether a steam turbine drives the shaft directly, or only drives an electrical generator.

You answered my question with another question, which I then answered, to which you responded with another question.

Maybe it would help if you didn't have so many questions about something you already know everything about!

[sailorboy1]

Originally Posted by bobconnie

but ya can't run a turbine with a coal or a wood fired steam! just a thought from someone who has run steam engines with coal for heat !!

Wow, better not tell all the coal fired electrical plants, like the one across from my mooring, or the wood chip fired one up the road that I've done the water treatment on for years

[Nemo55]

Needs a side car to keep the firebox and boiler in.
And for those who think steam doesnt have what it takes,,there are steam powered dragsters which will knock your socks off.

Originally Posted by Celestialsailor

I've always wanted a steam powered motorcycle...

[klem]

Originally Posted by ArtM

Great post Klem.

I think that the original discussion was about piston-driven steam engines. The article referenced by the OP is about piston operated boats.

The original African Queen is operating today in Key Largo doing day charters. I'm not sure if it is piston or turbine driven, but I think it is piston driven, and I would suspect that the engine is driving the shaft directly.

I believe that the nuclear powered vessels we're talking about are electrically driven, isn't that right? Or are some of them shaft driven from the turbines?

ArtM, you are correct, I missed the link in the first post. Thanks. Steam engines do work at much reduced power levels although they need to be absolutely massive. Really cool though.

You can absolutely run turbines on steam produced by coal or wood, many people do. The key is that you need to superheat the steam (also called "dry") so that there are no water droplets in it. If there are water droplets, then they will erode the turbine blades because they hit them at unbelievable velocities coming out of the nozzles. All you need for a superheater is a combustion temperature which is above the saturation temperature of the steam at the superheater. This can be achieved with most fuels provided they are burned properly. People have also successfully used separators and a valve (provides a small bit of superheat) on lower pressure steam to run saturated steam through a turbine but I don't think that it is common. Running wet steam through a turbine would certainly not be good though.

[sailorboy1]

Originally Posted by ArtM

I don't know man. Your comments about the use of a diesel engine to produced DC power on a Nuclear powered submarine are boggling my mind. I don't know what to make of it. One of us seems to be "mildly confused".

It isn't me that is confused. I'm not going to brother explaining back-up electrical or propulsion power sources or how a nuclear subs power distribution system is designed! I was an plant operator for 11 years and an instructor for 7 years.

You don't know and should accept it!

PS - on the boat that I don't think you have, does your diesel charge the battery - produce DC power?

[ArtM]

Originally Posted by Don Lucas

It isn't me that is confused. I'm not going to brother explaining back-up electrical or propulsion power sources or how a nuclear subs power distribution system is designed! I was an plant operator for 11 years and an instructor for 7 years.

You don't know and should accept it!

PS - on the boat that I don't think you have, does your diesel charge the battery - produce DC power?

It's ok if you don't want to bother explaining whether the steam turbine drives the props directly, OR whether or not a nuclear submarine's props are electrically driven, OR why it would use diesel engines (which surely must be burning electrically produced oxygen) to produce electricity for such electrical propulsion (if indeed such electrical propulsion systems exist).

What I don't get is why you are going to such great pains to NOT explain them!

There are much easier ways to not contribute to a conversation.

[ArtM]

And you're right - I don't own a nuclear powered boat!

[foggysail]

True, steam is not an energy source but it is a means for energy conversion and an important one. And yes, it does suffer from poor efficiency as defined by Nicolas Léonard Sadi Carnot in 1824 with his so called Carnot Cycle. Most engineers were required to take at least one course in thermodynamics and are very aware of this means for energy transfer.

But using coal to produce steam has problems that are defined in many places if one chooses to look. The Pergs, Sierras, Greenies, Society of Concerned Scientists (now that is some BS! Send in $25 to them and those who cannot even spell scientist can be one) will get Obama to sic his dog Janis Jackson on your tail and life will no longer be easy for you.

Foggy

[Astrid]

Dare I presume to offer this site:



Nuclear Propulsion

[ArtM]

I guess he just didn't know the answers.

No matter. The point is that there are still steam powered boats in operation today, but that it's probably not going to be practical to small boat operations, and that if you did build one it would either be extremely noisy if it's a piston engine, or require some very complex mechanical components if it's turbine driven.

So I guess the next bit of this is whether you could buy or build a very small turbine powered steam engine, and if you did would it be more practical in any way than the piston-powered alternative.

Since I don't own a piston powered steam engine, the point that it would be extremely noisy is purely speculation on my point, probably based solely on old movies which I might be confusing with reality.

[Ti' Punch]

ArtM, Astrid has done you a service. Click the link for a good overview of a Navy nuclear propulsion system. What is not shown is the emergency diesel, which all US Navy subs have (with possible exception of NR-1). The purpose of the diesel is to turn a generator which then supplies the battery banks to power the emergency propulsion motor in the event of a problem with the reactor/steam system. The epm is pictured in the above link. Like the old school diesel boats, all modern submarines are equipped with snorkels which allow them to operate their diesels while submerged. I think you and Don are both behaving childishly.

To the OP, sorry for the hijack. I will cease and desist from all further interruptions.

[Celestialsailor]

Originally Posted by Don Lucas

An accident at a nuclear plant doesn't make it a nuclear accident.

No Don but it makes the result the same...Chernobyl, 3 mile Island and Fukushima all had the same results. Leaked radiation, loss of life and years of natural devastation.
To say an accident at a nuclear plant doesn't make it a nuclear accident, is like saying the grenade pin wasn't what killed you but the result is the same.

[sdowney717]

Originally Posted by klem

To the OP, I assume you are talking about all sizes of boats, not just really large ones?

Taking it from an engineering perspective (I used to work as a designer of steam expanders similar to turbines), steam can do a really good job of taking energy stored in a wide variety of fuels and allowing it to be made into shaft work. However, this process while simple in principle, involves many steps. You need a boiler (with a superheater for a turbine) with fuel pumps, controls, feed water pumps, etc, lots of piping and safety valves, traps, a control valve, an expander, and a condensor. Not only is this a ton of stuff, at each step you loose a little efficiency. In the end, you get shaft work which you need to do something with. Small turbines spin at very high rpms so you either need a big reduction box or you need to spin a high speed generator.

Ok, I understand this but really the genius of the idea has to do with the much lower cost of the fuel even if it so much less efficient than gasoline or diesel.


There is a new external combustion engine which uses an expanding working fluid in a closed cycle and can burn any liquid fuel. So similar to steam power in use. Has a coil up top which is heated and drives the pistons.

2. Water contained in the coils becomes super-heated steam (up to 1200°F) in as little as 5 seconds from start up which is (a) piped to the cylinders, (b) where it enters through a patent-pending valve system (not pictured). Note, valve timing mechanisms regulate how much steam enters the cylinders – the longer the cut-off the greater the torque and acceleration.

any comments as this looks to be relatively simple motor package? Not having a lot of additional fluid valves, tanks, assorted engine hardware etc... as you noted in steam plants.
Cyclone Power Technologies - Cyclone Engine

[sdowney717]

A lot of buzz involving a thorium laser to turn water into steam to power cars.
Just 8 grams of thorium would drive you 300,000 miles.
And thorium is in very plentiful supply.
Thorium is a next generation power plant technology.

Laser Heating
Thorium lasers: The thoroughly plausible idea for nuclear cars | Txchnologist
The LPS power plant, for all its whiz-bang properties, isn’t a complete departure from traditional power generation: the thorium is lased and the resulting heat flashes a fluid and creates pressurized steam inside a closed-loop system. The steam then drives a turbine that turns an electric generator.

A 250-kilowatt unit (equivalent to about 335 horsepower) weighing about 500 pounds would be small and light enough to put under the hood of a car, Stevens claims. And because a gram of thorium has the equivalent potential energy content of 7,500 gallons of gasoline, LPS calculates that using just 8 grams of thorium in the unit could power an average car for 5,000 hours, or about 300,000 miles of normal driving.

Somehow we should get beyond our limitations on fuel choice and deliver some realistic competition to the oil companies. I would have little hesistation to using a steam engine heated by a thorium laser.

http://www.ensec.org/index.php?optio...ent&Itemid=342

Thorium mining is an entirely different proposition. Large supplies of thorium exist in surface mineral sands in nearly every corner of the world. These sands can be mined by dredge mining, which is well-known as being an environmentally unobtrusive mining technique. Without having to go underground, the infrastructure and operating costs are a small fraction of any uranium mining operation. These mineral sands are also highly concentrated with thorium, and can contain tens or hundreds of millions of pounds of thorium per deposit. In short, thorium is readily, cheaply and easily available in large quantities. The US itself has enough easily-extractable thorium to power its reactors for thousands of years.

The Nuclear Green Revolution: World Uranium and Thorium Supplies

https://www.google.com/webhp?sourcei...w=1120&bih=623