- Flywheels are old but mature and reliable.
- super-capacitors have highest power density but lower energy density than flywheel. meaning they take larger space or weight to store the same amount of energy, but discharge the same amount of energy in much shorter time (higher power).
- There are many different type of flywheel applications. The EM catapult is unique in that its charge time is long in many minutes, but discharge in 2 or 3 seconds. No other flywheel does that.
- If super-capacitors can reduce their footprint (volume), they are better than flywheel in EM catapult for their high power density. But that is not realized yet, so flywheel is the only option for the moment for 003 particularly.
- However, super-capacitors are used in rail-guns because the much lower energy density requirement than catapult.
CV-18 Fujian/003 CATOBAR carrier thread
- Thread starter Jeff Head
- Start date
Stupid question: What is the real advantage of having a nuclear powerplant instead of burning bunker fuel besides range?
I have experience in commercial shipping and if taking the large commercial bulkers/tankers/containers as reference, a conventionally powered ship can perform voyages for 50-100 days after a single bunker stop depending on speed (50d at full speed and 100d on eco, that‘s about 3000nm or half the globe).
Now I would imagine that 3.5 months is pretty much stretching food provisions (ignoring the crew now, crew changes in commercial shipping happenevery 6 odd months) so a resupply will be needed in any case without which the combination of vessel+crew isn‘t able to function properly anymore. Open waters ship-to-ship transfers aren‘t exactly an exotic thing either and for what I guess the operational area to be, an MR tanker would be more than enough.
So in absence of having to sail halfway across the globe and still be able to fight battles at arrival, what would be the other operational benefits of being nuclear powered?
Well it makes you less dependent on supplies. Yes you have unlimited range. Some modern nuclear reactors can even last 30 years without refueling. Traditional ones required a refueling every 5 years or something like that. You have so much power you can desalinate water easily. So you basically can have all the drinking water and bath water on board you want. And unlike in commercial shipping for cargo you will have thousands of people operating aboard the carrier. You have the crew, and all the support staff for the aircraft. This includes crew, mechanics, you name it. Easily thousands of people. The reactor is compact. You basically don't need the space you would use for fuel tanks. That can instead be used for other things be it cargo or more aircraft.
Intrepid
Major
Ford has three sets of four Wheels each for four catapults. The connecting device between three sets to for catapults was a big issue.
Thanks.
As four wheels is a set that drive a rail, three sets means that three catapults can be launching at the same time. As of the issue, I am curious what that could be.
Another interesting difference between the Chinese and the American systems are that China uses self-excitation generator while US use permanent magnet.
I am only into the catapult things. Not knowledgeable in the power-plant. The subject of Nuclear vs. conventional power-plant for a carrier has been hotly debated everywhere including this forum. Maybe some other members can better answering you, or you can try to read through the old posts, I know it is tiresome.
The only advantage that I heard that makes sense to me is that a nuclear CV will save its bunker fuel space for ammunition and aircraft fuel, it also reduce fuel replenish demand that can be used by other ships in the battle group.In short though, I can say, it really depends on your mission profile, doctrine, oversea bases etc. when choosing one over the other.
Intrepid
Major
of the battle group.
A nuclear powered aircraft carrier can travel at high speed over long distances. A conventional aircraft carrier can travel even at very high speed, but only for a short time. Both generate enough energy for the catapults, whether in the form of steam or electricity.
The assessment wasn't done in wartime environment.
However there is a big question the effectiveness of carriers in a world war, against AShM missiles
Aside from not needing fuel, there are other advantages.
1. Nuclear reactors do not need to vent flu-gas, so the island construction is smaller and can be placed more optimally for runways. The location of the engine can now be more optimally placed for carrier operation.
2. diesel engines plus fuel take up a lot more internal space which now could be allocated for other things like more aircrafts and air fuel.
3. There is an upper limit to how much one can scale the engines to the size of the carrier, so conventional fuel engine carriers hit size limit earlier then nuclear ones. if you can increase the size by 50%, It adds 2x the power for a carrier. Nuclear power carriers can be larger.
4. Carriers typically need to travel at least at 30 knots. Due to the size of the engines, the amount of power in excess of requirement at top speed is limited for conventional power carriers. More excess power of the nuclear carriers allow the carrier to do more things.