What happens if you boil water in this situation?

[Goldspoon]

... if you put water in a vessel that is extremely strong e.g. 6" thick steel and then add heat to the point where it boils.

the water (at some stage) boils and turns to steam and expands 1600X

What if the container is SO strong that the container cannot be broken?

The water expands + the container is strong enough to hold it...

what happens?

May not be right for the plumbing section as is a spurious "what if" but thought a plumber might be most likely to know...

 

[kevplumb]

What if the container is SO strong that the container cannot be broken?

The water expands + the container is strong enough to hold it...

nothing

 

[glasgowgas]

ah the old but what if..........

a vessel holds 100 litres and its trying to be occupied by 1600 litres of steam.........


BOOM!

 

[JohnD]

Boiling point of water is dependent on pressure. Higher pressure ==> higher boiling point

I surmise that in a closed container, the initial boil will raise the pressure to a level where more water does not boil.

I am extrapolating from a car radiator (which I have seen) to a Pressurised Water Reactor (which I haven't) but sounds rather like your strong sealed container

I don't know the working temp of a PWR.

I bet you know the answer anyway.

p.s. If it was on a conveyor belt, it would explode

 

[dextrous]

ah the old but what if..........

a vessel holds 100 litres and its trying to be occupied by 1600 litres of steam.........


BOOM!

But not if it's a cheap copper cylinder made in France. Then it's as safe as houses

 

[Boilerman2]

You have my Friend, invented THE STEAM BOILER, sadly about 160 Years TOO LATE

 

[Boilerman2]

How A Steam Boiler Works.

Boiler shell is not completely filled with water, there is a space at the top of the boiler for steam to form, as the Burner raises the temperature to 100'c the water boils, dry steam is formed in the space above the weater level, which increases the pressure within the boiler, this slows the boil rate (Raising the Pressure Increases the Boiling Temperature of Water)

In your scheme however, you make no mention of a pressure Switch to control the Burner, or a Boiler Safety Valve, so eventially something would give and as has been mentioned - BOOM!

In a real boiler the working pressure would be controlled by a pressure switch, the water level would be maintained by a feed pump controlled by Level switches and 1st & 2nd stage Low Water protection would also be required

I MUST SAY THAT THIS IS THE MOST BIZZARE POST!!

 

[dextrous]

Sounds like the unstoppable force against the immovable object paradox.

 

[JayJay1978]

I don't think its a bizare post, Goldspoon was merely trying to get his head round what would happen in that situation.

These days information is at you're finger tips but I bet someone 160 years ago blew themselves up trying to find an answer!

 

[mgheating]

reminds me of this

http://www.youtube.com/watch?v=ekEHfihiNz4

i think there is at least one other vid of an unvented cylinder exploding on youtube.

I'd bloody love to recreate that....in a field obviously!

 

[Goldberg]

What if the container is SO strong that the container cannot be broken?

If it can't be broken then it won't break.

The water expands + the container is strong enough to hold it...

If it's strong enough to hold it then it won't stop holding it.

what happens?

It holds water, water vapour, and steam, all at an immensely high pressure.

 

[bengasman]

What you are describing is effectively the same as a gasbottle. When the water is heated enough to turn into gas, but the there is not enough room to expand, you end up with liquid pressed gas.
Most gasses turn into liquid if you compress them enough, steam is no exception.

 

[IJWS15]

Would have to dig out my steam tables to check but IIRC a power station HP turbine runs on steam at 575 degrees centigrade and over 100 atmospheres.

Obtained by heating huge volumes of water in just such a confined space - also known as a superheater.

My wife still believes that if a pan bubbles more then the water is hotter than boiling. Have tried to explain the science but she just does not undertand (or want to know??)

A pressure cooker does some of what you suggest by not allowing the steam to expand and limiting pressure rise by using weights and a pressure relief valve.

Don't try this at home - by blanking the pressure relieve valve and adding more weights to the top of the pressure cooker you could create your situation for real, but the pressure cooker WILL explode at some point producing LETHAL metal fragments and LETHAL superheated steam. Your kitchen walls are not built to withstand this sort of explosion and would probably collapse. THis is why pressure cookers have TWO safety systems.

For similar reasons you do not presure test systems with air but with water.

By the way - you cannot see steam, you can only see water vapour (condensed water in the air).

 

[iconic]

My wife still believes that if a pan bubbles more then the water is hotter than boiling. Have tried to explain the science but she just does not undertand (or want to know??)

I would like to know - please could you explain the science to me?

 

[kevplumb]

looking for another thread to start a row in are we