Engines; The Heart any War-Machine

[no_name]

Richard Feynman first wrote something about it. He never meant to be serious.
He's a cool guy.

 

[below_freezing]

I meant, hybrid solar-petro destroyers. Solar for powering relatively low powered electrical systems such as computers and gun targetting while petro is reserved exclusively for engines, storage battery and radar.

An interesting problem on an exam a few years back was about the electrochemistry of a solar powered chemical fuel cell. the reactions were:

TiO2 + absorbant dye X + hv -> TiO2 + excited dye X*
TiO2 + excited dye X* -> TiO2 + dye ion X+ + e-
I3- + 2e- -> I2 + I-
2 TiO2 + dye ion X+ + 3I- -> 2TiO2 + absorbant dye X + I3-

(anode is the TiO2,

Not sure if this cell is commercially viable though. A thin transparent layer of the solid state dye can be deposited on a glass substrate, then TiO2 on top of that, with the iodine aqueous solution on top sealed in by another transparent glass layer connected to a conductive surface acting as the positive electrode.

 

[no_name]

The Americans tried it, shielding the crew was too difficult, they gave it up.

The one engine they got working was a direct drive system and spewed radiation wherever it flew.

I just though that with UAVs and a shielded part of the aircraft carrier this problem will be solved. Though it's a bit dirty for the enemy civilians in the path of flight .

Though i guess military planes are already expensive enough. No point of making them nuclear powered if you are likely to lose them. Besides, the armament you can carry is not gonna allow you to stay up there for enough time for advantages to be significant enough.

If you make it fast enough/high enough to evade missiles, it could be a wonderful ultra long endurance surveillance plane. But with development of laser weapons the risk is still high.


Stealth might become very important with development of long range laser weapons. Once you are detected there is pretty much little chance of surviving.

 

[no_name]

I meant, hybrid solar-petro destroyers. Solar for powering relatively low powered electrical systems such as computers and gun targetting while petro is reserved exclusively for engines, storage battery and radar.

An interesting problem on an exam a few years back was about the electrochemistry of a solar powered chemical fuel cell. the reactions were:

TiO2 + absorbant dye X + hv -> TiO2 + excited dye X*
TiO2 + excited dye X* -> TiO2 + dye ion X+ + e-
I3- + 2e- -> I2 + I-
2 TiO2 + dye ion X+ + 3I- -> 2TiO2 + absorbant dye X + I3-

(anode is the TiO2,

Not sure if this cell is commercially viable though. A thin transparent layer of the solid state dye can be deposited on a glass substrate, then TiO2 on top of that, with the iodine aqueous solution on top sealed in by another transparent glass layer connected to a conductive surface acting as the positive electrode.

Maybe. But the top of ships is not exactly a flat terrain, and deck space is a luxury competed by other equipment, heli, missile and what have nots. And I wonder if the savings would worth all that trouble.

But I think if you can develop flecible, thin enough and light enough solar films they might be very useful for applications such as powering surveillance blimps and ballons etc where you can just paste the film on the outer skin.

 

[marshall]

I meant, hybrid solar-petro destroyers. Solar for powering relatively low powered electrical systems such as computers and gun targetting while petro is reserved exclusively for engines, storage battery and radar.

Using solar is totally unrealistic and a waste of valuable deck space. If every square inch of a ship were covered with solar panels with 24/7 overhead sunshine at 100% electricity generating efficiency, I would be very surprised if it could generate even 0.1% of the power a warship requires. The nuclear reactor of Nimitz class aircraft carriers generates nearly 200 megawatts of power. This is constant baseload power that isn't dependent on whether it is cloudy or not, nighttime, storing power in bulky batteries, etc. Solar is a waste of time, it's not even suitable for low power density applications like cars let alone an ultra-energy intensive platform like a warship.

Solar power is a low-density power source. Despite it's abundance, it requires so much resource investment IN COMPARISON to what little electricity is generated, that it's ultimately a waste of time and money given the alternatives. China should concentrate on liquid thorium reactors (Molten Salt Reactors) to power it's navy and its commercial power plants. This is an essentially limitless source of power and would make China 100% energy independent in addition to eliminating 99% of air pollution (makes coal/gas power plants uncompetitive, makes gas powered vehicles uncompetitive) and giving it's warships unlimited endurance. It would also allow China to develop industrially on a per capita and nominal scale now impossible because of energy limitations.

Luckily China's leadership has embarked on a liquid thorium reactor energy path. Once this technology is commercialized, I believe it will solve pretty much all of China's strategic problems, with the exception of its border disputes with India and Japan.

 

[CardSharp]

I meant, hybrid solar-petro destroyers. Solar for powering relatively low powered electrical systems such as computers and gun targetting while petro is reserved exclusively for engines, storage battery and radar.

An interesting problem on an exam a few years back was about the electrochemistry of a solar powered chemical fuel cell. the reactions were:

TiO2 + absorbant dye X + hv -> TiO2 + excited dye X*
TiO2 + excited dye X* -> TiO2 + dye ion X+ + e-
I3- + 2e- -> I2 + I-
2 TiO2 + dye ion X+ + 3I- -> 2TiO2 + absorbant dye X + I3-

(anode is the TiO2,

Not sure if this cell is commercially viable though. A thin transparent layer of the solid state dye can be deposited on a glass substrate, then TiO2 on top of that, with the iodine aqueous solution on top sealed in by another transparent glass layer connected to a conductive surface acting as the positive electrode.

Looks like TiO2 is the catalyst and not an (anode?)

 

[Chogy]

The Americans tried it, shielding the crew was too difficult, they gave it up.

The one engine they got working was a direct drive system and spewed radiation wherever it flew.

While the nuclear engine flew a bit, it was never used to actually power the B-36 carrier vehicle. Yes, shielding is a problem, but worse is the inevitable crash. Nuclear aircraft engines simply are not practical, even for UAV's. Too dangerous.

Nuclear ship/sub engines are more practical because they are not really limited by weight, can be contained very thoroughly, and in the event of destruction, they (hopefully) sink deep and any leakage is massively diluted by sea water so as to become not much more than background radiation any distance from the wreck.

 

[below_freezing]

While the nuclear engine flew a bit, it was never used to actually power the B-36 carrier vehicle. Yes, shielding is a problem, but worse is the inevitable crash. Nuclear aircraft engines simply are not practical, even for UAV's. Too dangerous.

Nuclear ship/sub engines are more practical because they are not really limited by weight, can be contained very thoroughly, and in the event of destruction, they (hopefully) sink deep and any leakage is massively diluted by sea water so as to become not much more than background radiation any distance from the wreck.

How small are current reactor designs for carriers? Like height, diameter, volume?

 

[Chogy]

How small are current reactor designs for carriers? Like height, diameter, volume?

I am not a nuclear scientist, but I do know that they have different styles of reactors, and some, like the "nuclear battery", can be very small and light. Any space probe outside the orbit of Mars requires one because the sunlight density is too low for solar panels. Nuke batteries can provide a few hundred watts for decades, in a package a man can lift.

Actual nuclear engines/turbines as used on subs and large ships must provide hundreds of thousands of horsepower for years, and are massive. They use the heat of controlled fission to heat up a working fluid (like water) which then goes through a turbine. The shaft then drives generators and propellers. A nuclear aircraft carrier has the capacity to power a small city, and in fact, in a disaster scenario, one of them in a port can be cabled right into the local grid, if needed.

 

[casual]

nuclear is the way to go for high powered systems. solar could work for low powered devices like remote sensing uavs. better battery technology is needed tho.

 

[CardSharp]

I wonder if it is possible to build a direct drive nuclear engine for something like a submarine similar to what they did in the medium of air for the nuclear bomber.

Probably pretty loud though...

 

[applesauce]

I wonder if it is possible to build a direct drive nuclear engine for something like a submarine similar to what they did in the medium of air for the nuclear bomber.

Probably pretty loud though...

why worry about noise, the enemy would just following the trail of dead ocean life you leave behind and the radioactive water trail

 

[CardSharp]

why worry about noise, the enemy would just following the trail of dead ocean life you leave behind and the radioactive water trail

lol True, but it would be a shield direct drive I think.