CV-18 Fujian/003 CATOBAR carrier thread

[Wrought]

Interesting read I found comparing Fujian and Ford:

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No, it repeats the long-debunked narrative about supercapacitors. Fujian uses flywheels.

PLAN Catapult Development Thread, News, etc.

A EM torpedo revolver launcher by Naval engineering university. Application date March 2022. CN114543589A 一种全浸没多联装电磁发射装置 Fully submerged in liquid/sea water when stored. No need to flood the tube before launch. Torpedos are stored in their own compartment outside of pressure hull.

www.sinodefenceforum.com

 

[vincent]

No, it repeats the long-debunked narrative about supercapacitors. Fujian uses flywheels.

PLAN Catapult Development Thread, News, etc.

A EM torpedo revolver launcher by Naval engineering university. Application date March 2022. CN114543589A 一种全浸没多联装电磁发射装置 Fully submerged in liquid/sea water when stored. No need to flood the tube before launch. Torpedos are stored in their own compartment outside of pressure hull.

www.sinodefenceforum.com

The text posted by taxiya didn’t specifically said flywheels were used in 马伟明’s system.

A 125kwh flywheel system used by a coal fire power plant can be seen in this video.

The spinning wheel weights 10 tons. It can be seen at 19:50. Vibration can be catastrophic.

With ships constantly bobbing up and down, left and right, I don’t see how flywheels can be used on ships. Even if they are placed on a balance board, the ship may drop vertically if it hits a large wave.

 

[FairAndUnbiased]

The text posted by taxiya didn’t specifically said flywheels were used in 马伟明’s system.

A 125kwh flywheel system used by a coal fire power plant can be seen in this video.

The spinning wheel weights 10 tons. It can be seen at 19:50. Vibration can be catastrophic.

With ships constantly bobbing up and down, left and right, I don’t see how flywheels can be used on ships. Even if they are placed on a balance board, the ship may drop vertically if it hits a large wave.

I have my doubts about flywheel too. From my understanding, conservation of angular momentum will mean the flywheel resists at least 2/3 motions of pitch/roll/yaw, which creates huge shear stress on the axle and bearings if the flywheel is fixed.

The shear stress is also not consistent as it moves with the waves. A regular noise dampening platform doesn't work as the degree of motion caused by waves and steering is far greater than engine vibrations. It will need to be floated in a 3D gyroscopic manner. Which is something we not only don't see but even theoretically causes problems with size, weight, reliability, etc.

 

[valysre]

It will need to be floated in a 3D gyroscopic manner. Which is something we not only don't see but even theoretically causes problems with size, weight, reliability, etc.

I had the same thought. Any kind of suspension of the spinning wheel to allow it to take advantage of any gyroscopic properties seems difficult, to say the least. It also makes it more difficult to get energy in and out of the wheel, if it's floated. Then again, I don't know much about this. Maybe some group of geniuses has worked out a way to do it.

 

[Moonscape]

Super capacitors are at least plausible.

Pseudocapacitors can get 10 Wh/kg in density and 10 W/g in power.

Accelerating a 30 ton object to 150 knots requires 0.5*30000*77^2 = 89 megajoules of energy, round up to 90 MJ.

90MJ/36000(J/kg) = 2500 kg. This should also be able to discharge at 25 MW, so you can transfer a total of 90 MJ of energy in under 4 seconds.

So a 2.5 ton super capacitor could theoretically power an EM cat. Probably similar in weight to an equivalent 90MJ (25 kwh) flywheel + support system, but solid state and much more reliable.

Not to say that's what's actually being used, but it's plausible.

 

[Wrought]

The text posted by taxiya didn’t specifically said flywheels were used in 马伟明’s system.

A 125kwh flywheel system used by a coal fire power plant can be seen in this video.

The spinning wheel weights 10 tons. It can be seen at 19:50. Vibration can be catastrophic.

With ships constantly bobbing up and down, left and right, I don’t see how flywheels can be used on ships. Even if they are placed on a balance board, the ship may drop vertically if it hits a large wave.

I have my doubts about flywheel too. From my understanding, conservation of angular momentum will mean the flywheel resists at least 2/3 motions of pitch/roll/yaw, which creates huge shear stress on the axle and bearings if the flywheel is fixed.

The shear stress is also not consistent as it moves with the waves. A regular noise dampening platform doesn't work as the degree of motion caused by waves and steering is far greater than engine vibrations. It will need to be floated in a 3D gyroscopic manner. Which is something we not only don't see but even theoretically causes problems with size, weight, reliability, etc.

I had the same thought. Any kind of suspension of the spinning wheel to allow it to take advantage of any gyroscopic properties seems difficult, to say the least. It also makes it more difficult to get energy in and out of the wheel, if it's floated. Then again, I don't know much about this. Maybe some group of geniuses has worked out a way to do it.

Never mind Fujian for a second, we've literally known Ford is using flywheels for decades now. This is public information. How on earth can anyone doubt that they work on ships?

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And regarding Fujian specifically, it was confirmed to use flywheels several years ago.

CV-18 Fujian/003 CATOBAR carrier thread

GlobalTimes uses "EM catapults" and actively avoiding terms like "Chinese EMALS" when describing EM catapults on Fujian. (source) On the other hand, GlobalTimes informally uses "Chinese AEGIS" to describe Type 052D AESA radar, portraying it as a peer of contemporary USN ships equipped with the...

www.sinodefenceforum.com

I thought all of this was well-established and accepted information by now. I feel like I'm taking crazy pills.

 

[FairAndUnbiased]

Never mind Fujian for a second, we've literally known Ford is using flywheels for decades now. This is public information. How on earth can anyone doubt that they work on ships?

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And regarding Fujian specifically, it was confirmed to use flywheels several years ago.

CV-18 Fujian/003 CATOBAR carrier thread

GlobalTimes uses "EM catapults" and actively avoiding terms like "Chinese EMALS" when describing EM catapults on Fujian. (source) On the other hand, GlobalTimes informally uses "Chinese AEGIS" to describe Type 052D AESA radar, portraying it as a peer of contemporary USN ships equipped with the...

www.sinodefenceforum.com

I thought all of this was well-established and accepted information by now. I feel like I'm taking crazy pills.

This is not a problem with well characterized solutions.

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Note the date of publication.

Flywheels in naval electrical applications are not trivial to solve. It isn't guaranteed to be easier than a supercapacitor. You are just trading electrical and chemical problems for mechanical ones.

 

[Wrought]

This is not a problem with well characterized solutions.

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Note the date of publication.

Flywheels in naval electrical applications are not trivial to solve. It isn't guaranteed to be easier than a supercapacitor. You are just trading electrical and chemical problems for mechanical ones.

Of course it's not trivial, which has no bearing on the fact that both US and Chinese carriers have already used them to launch aircraft. Flywheels very obviously work; we've literally seen them working.

 

[FairAndUnbiased]

Of course it's not trivial, which has no bearing on the fact that both US and Chinese carriers have already used them to launch aircraft. Flywheels very obviously work; we've literally seen them working.

I have not seen a single photo of the supposed Fujian flywheel or even its associated engineering space.

 

[Wrought]

I have not seen a single photo of the supposed Fujian flywheel or even its associated engineering space.

If you want to doubt the word of Yankee and co. then be my guest, but his record is a lot stronger than yours.