Type 054B/next generation FFG thread


blindsight

Junior Member
Registered Member
Hydraulic dampeners can also cancel out lower frequency noises, and they did exactly just that for the 054A and 056 series. You can also reduce vibrations further with viscous dampers, counterbalancing or contrarotating shafts, flexible engine mounts, stiffening the engine block, and even to controlling the fuel injection.
It's similar for cars, for example. You have a lot of engine configurations, such as V6, having inherent 1st order imbalance, but in most cases, for example, most 60-degree V6s, you just live with it because hydraulic engine mount and other normal dampening mechanism does the job well. However, for I4 with inherent 2nd order imbalance, usually you would need counter-rotating twin balancer shafts to help cancel the vibration, although the absolute amount of NVH is actually weaker. That's all because of the higher frequency nature of this 2nd order thing.
 

Tam

Brigadier
Registered Member
You'll have to pay. lower efficiency, lower output...

Tell that to the shipbuilders and ship buyers.

Despite electrical propulsion, despite gas turbines, despite the shilling the makers of such, more and more each year, new ships are built with reciprocating engines.
 

Tam

Brigadier
Registered Member
It's similar for cars, for example. You have a lot of engine configurations, such as V6, having inherent 1st order imbalance, but in most cases, for example, most 60-degree V6s, you just live with it because hydraulic engine mount and other normal dampening mechanism does the job well. However, for I4 with inherent 2nd order imbalance, usually you would need counter-rotating twin balancer shafts to help cancel the vibration, although the absolute amount of NVH is actually weaker. That's all because of the higher frequency nature of this 2nd order thing.

Like you have no idea what marine diesels are.

Talk about V8s, V10s, V12s, I8s, I12s even I16s.

16 Pielstick PA6 should be a 16 cylinder engine, a V-16, eight cylinders in one bank, another eight in the other.
 

blindsight

Junior Member
Registered Member
Tell that to the shipbuilders and ship buyers.

Despite electrical propulsion, despite gas turbines, despite the shilling the makers of such, more and more each year, new ships are built with reciprocating engines.
For surface combatants, I'm not sure about that...
 

blindsight

Junior Member
Registered Member
Like you have no idea what marine diesels are.

Talk about V8s, V10s, V12s, I8s, I12s even I16s.

16 Pielstick PA6 should be a 16 cylinder engine, a V-16, eight cylinders in one bank, another eight in the other.
I was just using that as an example to support what I said about the frequency of noises. I may know more about marine diesels than you thought, so please don't put your effort in this direction...
 

Tam

Brigadier
Registered Member
For surface combatants, I'm not sure about that...

Type 075 is running diesels. So does the Type 901.


Here is how the 16 Pielstick PA6 should look like. You think this is an I4 engine?

image-placeholder-title.jpg

engines.jpeg

See the top right corner. The current engine running the Type 054A should be on the far right of the table with the previous being the third from the right.
 

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