dyqik t1_j6p34o3 wrote on January 31, 2023 at 10:06 PM

Reply to comment by Hribunos in Massive ship in the harbor this morning by NAFAL44

It wouldn't stay frozen or have much ability to freeze anything for long - the ocean is big [citation needed] and cryogenic liquids really don't have a lot of heat capacity compared to water.

Freezing stuff also usually doesn't damage much, unless there's water to expand inside it.

Hribunos t1_j6pfqs9 wrote on January 31, 2023 at 11:30 PM

Have you ever seen LN2 skittering across a floor? It's like that. There wouldn't actually be that much heat transfer from the ocean- the LNG would skate across the surface on a thin layer of vapor.

I used to work in the seaport, and we ran the numbers - it's not enough to destroy building or whatever but anyone standing on the pier is gonna be a popsicle.

dyqik t1_j6pgjcm wrote on January 31, 2023 at 11:35 PM

I build cryostats and operate superconducting detectors - I've been handling liquid cryogens for over twenty years.

I've stuck my hand in liquid nitrogen hundreds of times.

The main danger from liquid cryogens is the displacement of oxygen from the area when it flash boils.

While small amounts of liquid will skate around on a vapor barrier (leidenfrost effect on solid surfaces), in volume, the boiling at the interface between water and the liquid will produce some amount of turbulence and mixing that increases heat transfer.