How would you calculate getting dunked in lava?

Shadow WarChief · Post by **Shadow WarChief** » 2003-03-23 02:27pm

...and could you give an example?

Just assume a cubic meter of iron

Basically I just need to know how to do this for some Transformers calculations I'm planning on doing.

InnerBrat · Post by **InnerBrat** » 2003-03-23 02:44pm

How would you calculate what exacftly about being dunked in lava?

Shadow WarChief · Post by **Shadow WarChief** » 2003-03-23 02:58pm

innerbrat wrote:How would you calculate what exacftly about being dunked in lava?

how much heat you'd absorb

InnerBrat · Post by **InnerBrat** » 2003-03-23 04:19pm

Shadow WarChief wrote:
innerbrat wrote:How would you calculate what exacftly about being dunked in lava?
how much heat you'd absorb

Depends on the temp of the lava, which would depend on the type of volcanism/ area...

Post by **Darth Wong** » 2003-03-23 04:31pm

Heat transfer between lava and a block of steel would be primarily convective transfer, and you would need to know:

A) the temperature of the lava

B) the convective heat transfer coefficient for a lava/steel interface (this is a nasty requirement since the fluid mechanics which control this sort of parameter are too complex to derive from first principles and are normally determined empirically)

C) the mass of the block

D) the surface area of the interface

Slartibartfast · Post by **Slartibartfast** » 2003-03-24 12:39am

I would calculate it in decibels. The amount of noise you make when you're screaming as your skin is seared from the heat and all that.

kojikun · Post by **kojikun** » 2003-03-24 01:24am

yeah, oddly i posted something about it being precisely 3.something shitloads or just about 93 helluvalots of heat. somehow it disappeared.

but yes, decibels is a good unit of measure

Post by **Darth Wong** » 2003-03-24 01:46am

I should point out that once you reach thermal equilibrium with the lava, the heat transfer rate will be zero. If an object is constructed out of materials which can remain solid and reasonably strong at the temperatures of lava, the heat flux will start high and then gradually decrease as it heats up until it reaches zero at the point of equilibrium, and the object can sit there pretty much indefinitely.

Rathark · Post by **Rathark** » 2003-03-25 08:01am

Just how realistic was the "leg-melting" scene in Volcano?

Death from the Sea · Post by **Death from the Sea** » 2003-03-25 01:46pm

I would say, not vary since you would most likely fall face first when your feet were gone.

Shrykull · Post by **Shrykull** » 2003-03-25 11:09pm

Darth Wong wrote:I should point out that once you reach thermal equilibrium with the lava, the heat transfer rate will be zero. If an object is constructed out of materials which can remain solid and reasonably strong at the temperatures of lava

Really? I didn't think anything could remain solid while it was immersed in the lava? What's the melting point of diamond for example? I heard it was real high even though it's just pure carbon.

Shrykull · Post by **Shrykull** » 2003-03-25 11:12pm

Shadow WarChief wrote:...and could you give an example?

Just assume a cubic meter of iron

Basically I just need to know how to do this for some Transformers calculations I'm planning on doing.

Guess, you saw that episode too, where Megatron, and the other feel in, I thought maybe they were all dead at first, then they just lied there like they were taking a bath.

Post by **Darth Wong** » 2003-03-25 11:43pm

Shrykull wrote:
Darth Wong wrote:I should point out that once you reach thermal equilibrium with the lava, the heat transfer rate will be zero. If an object is constructed out of materials which can remain solid and reasonably strong at the temperatures of lava
Really? I didn't think anything could remain solid while it was immersed in the lava? What's the melting point of diamond for example? I heard it was real high even though it's just pure carbon.

Since the average temperature of lava is only around 1500K, there are lots of materials which can remain solid. Even ordinary steel will remain solid, although its strength will be shit. Cobalt-based superalloys will be not only solid but serviceable at that temperature. Similarly, refractory ceramics have no problem.

Post by **Sea Skimmer** » 2003-03-25 11:47pm

Rathark wrote:Just how realistic was the "leg-melting" scene in Volcano?

Pure bullshit

kojikun · Post by **kojikun** » 2003-03-26 12:07am

cobalt superalloys? PROVIDE A LINK!!

::engineering mental orgasm::

SAMAS · Post by **SAMAS** » 2003-03-26 01:33am

Shrykull wrote:
Shadow WarChief wrote:...and could you give an example?

Just assume a cubic meter of iron

Basically I just need to know how to do this for some Transformers calculations I'm planning on doing.
Guess, you saw that episode too, where Megatron, and the other feel in, I thought maybe they were all dead at first, then they just lied there like they were taking a bath.

Of course, I think Flint and Lady Jaye did that once, too.

Shadow WarChief · Post by **Shadow WarChief** » 2003-03-26 02:56am

Shrykull wrote:

Guess, you saw that episode too, where Megatron, and the other feel in, I thought maybe they were all dead at first, then they just lied there like they were taking a bath.

Actually they came out burnt after 21 seconds of exposure. It's BW Dragon Megatron that came out of lava looking like he had a bath, and he stayed under for 7 times as long.

But I digress...

How much does the convective heat transfer coefficient vary between lava/steel?
Is there some rough range over which a value can be used?

StarDestroyer.Net BBS

How would you calculate getting dunked in lava?

How would you calculate getting dunked in lava?

Re: How would you calculate getting dunked in lava?

Re: How would you calculate getting dunked in lava?

Re: How would you calculate getting dunked in lava?