Related thoughts: turbo-pressurized boilers are absolutely an insane idea for ship propulsion. 1/n arstechnica.com/?post_type=pos…
So, there was a time when superpressurized steam was the best power-to-weight ratio propulsion for combatant ships. That period was prior to 1985. Generally speaking, everyone has gone to (1) gas turbines, (2) diesel engines, (3) nuclear steam for special cases.
Starting in the 1950s, the US Navy went to 1200 PSI steam systems based on the D-type boiler design: fas.org/man/dod-101/na…
1200 psi steam was temperamental as fsck. Had great power density, but also you ran the risk of pipes blowing, and people getting sliced in half by steam leaks. And because of the pressures, stuff broke a lot. Also, when a boiler goes offline, relighting is a major pain in ass.
No steam, no power or propulsion. Dead in the water. In the dark, running emergency diesels maybe to pump the oil into the boiler and refire with a long stick with fire on it. Yay.
Screw up the air mix in a boiler with nozzles spraying diesel fuel marine or other petroproduct into a giant pressurized firebox, and you're gonna have a problem. Black smoke: you're not getting enough air. White smoke: too much combustion air, and raw unburned fuel 💥risk.
So, when Admiral Kuznetsov smokes black like coal dust, that's unburned carbon in the air. Which is the best sort of bad news you can have with a superpressurized boiler. White smoke means dasvidaniya, Ivan.
Now, US D-type boilers on many ships were "forced draft"--blowers pushed air into the fire box to ensure a good supply of air. So they were high-pressure boilers, in that air was injected into them above atmospheric pressure--in part to make sure air went out the stack.
But the US and everyone else except Russia pretty much figured out gas turbines and diesel were safer and more weight-efficient sources of power, and as they've gotten better GTs are now used for every size of US non-nuke ship. Steam with glowrocks remains for supercarriers, subs
Also, less risk of an earth shattering kaboom with GTs and diesel. But Russia.
The Kuznetsov went with *turbopressurized* boilers: steam powered turbines drove air into the boilers to create an even higher pressure, just as turbocharged car engines force more air into combustion.
The Kuznetsov went with *turbopressurized* boilers: steam powered turbines drove air into the boilers to create an even higher pressure, just as turbocharged car engines force more air into combustion.
Russia could have gone with nuclear propulsion--for crying out loud, they had nuclear icebreakers. But they did not have the power needed to move the Kuznetsov fast enough for air ops, I guess. So these crazy round vertical boilers were designed.
Turbocharging your boiler ups the risk of white smoke if you do not have fine control over air injection. It also ups the boiler pressure even further. So...insanity. Plus the pressures make the boilers incredibly prone to breakdowns, oil leaks, engine room fires...you name it.
Even the new LHAs in the America class use turbines now because they're safer and more space efficient from a power perspective. The Kitty Hawk was the last US steam powered ship.
And just for perspective: most US steam-powered combatants were basically steam plants with a hull and living space built around them. Aboard USS Iowa, the engineering spaces consumed about 70 percent of the ship's internal volume.
I mean CARRIER. There are still LHDs in service that use steam.
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