The London Underground are investigating the possibility of using water to
cool down underground stations.
http://news.bbc.co.uk/1/hi/magazine/3897899.stm

Personally I favour the idea of handing out free ice lollies.

"Ted Maul" wrote in message
...
The London Underground are investigating the possibility of using water to
cool down underground stations.
http://news.bbc.co.uk/1/hi/magazine/3897899.stm

Personally I favour the idea of handing out free ice lollies.

Did anyone else enter the £100k competition set by LU for tube cooling
ideas? I did but I never heard anything back. I wonder if a winner has
been announced?

Angus

On Fri, 16 Jul 2004, Ted Maul wrote:

The London Underground are investigating the possibility of using water
to cool down underground stations.

It's an interesting problem, the cooling. It's easy to pump heat out of
the carriage into the tunnel (that's normal air conditioning), and that'll
work fine when the trains are above ground, but it's rather harder to get
heat from the tunnel to the outside. Three options spring to mind: pump
warm air out (which means moving a lot of air), transfer the heat into
water and pump that out (which means moving a bit of water, but
transferring a lot of heat), or transfer the heat into some kind of
reservoir on the train and then dispose of it when outside (which means
either pumping the heat out, or just using water to hold the heat and then
dumping it, neither of which is going to be that easy).

Anyway, interesting as the problem is, i'd be even more interested in a
solution!

And are we going to get dehumidifers as well? And perhaps filters on the
Northern line ...

tom

--
I know you wanna try and get away, but it's the hardest thing you'll ever know

"Tom Anderson" wrote in message
...
On Fri, 16 Jul 2004, Ted Maul wrote:
The London Underground are investigating the possibility of using water
to cool down underground stations.

It's an interesting problem, the cooling. It's easy to pump heat out of
the carriage into the tunnel (that's normal air conditioning), and that'll
work fine when the trains are above ground, but it's rather harder to get
heat from the tunnel to the outside. Three options spring to mind: pump
warm air out (which means moving a lot of air), transfer the heat into
water and pump that out (which means moving a bit of water, but
transferring a lot of heat), or transfer the heat into some kind of
reservoir on the train and then dispose of it when outside (which means
either pumping the heat out, or just using water to hold the heat and then
dumping it, neither of which is going to be that easy).

As I suggested some months ago, long low water tankers at front and back of
every train. The one at the rear sprays out a very fine mist of water which
will cool the air and then be drained out, taking the heat with it, just as
with any other water which gets into the underground system. I claim the
prize.
Cheerz,
Baz

Marratxi wrote:

As I suggested some months ago, long low water tankers at front and back of
every train. The one at the rear sprays out a very fine mist of water which
will cool the air and then be drained out, taking the heat with it, just as
with any other water which gets into the underground system. I claim the
prize.
Cheerz,
Baz

That would only work because of cooling effect of evaporating the water.
Once enough water has evaporated to raise humidity to near dew point
little more water would evaporate, AND you'd have an even more humid
sticky atmosphere. (It's evaporating the water that absorbs energy not
heating it from say 10degC to 15degC) (Hundred times as much!- I'll not
quote units as I'm sure to get cgs, MKS, & SI units muddled)

I'd suggest even with IDEA of using water pumped from sumps to cool air
you might need some sort of 'heat pump' in the circuit to enable waste
water to be at higher temperature than returned 'cooled' air.

Jim Chisholm

"J. Chisholm" wrote in message
...

As I suggested some months ago, long low water tankers at front and back
of
every train. The one at the rear sprays out a very fine mist of water
which
will cool the air and then be drained out, taking the heat with it, just
as
with any other water which gets into the underground system. I claim the
prize.

That would only work because of cooling effect of evaporating the water.
Once enough water has evaporated to raise humidity to near dew point
little more water would evaporate, AND you'd have an even more humid
sticky atmosphere. (It's evaporating the water that absorbs energy not
heating it from say 10degC to 15degC) (Hundred times as much!- I'll not
quote units as I'm sure to get cgs, MKS, & SI units muddled)

I'd suggest even with IDEA of using water pumped from sumps to cool air
you might need some sort of 'heat pump' in the circuit to enable waste
water to be at higher temperature than returned 'cooled' air.

A team at South Bank University have studied it for a couple of years.
Worth a look at the three papers they published if you're interested.
(Nothing particularly ground-breaking here, mind you!)

http://makeashorterlink.com/?H2D3138D8
http://makeashorterlink.com/?B1F3638D8
http://makeashorterlink.com/?I204328D8

It seems as though the groundwater cooling option is the one LU are
interested in.

Angus

Marratxi wrote:

As I suggested some months ago, long low water tankers at front and back of
every train. The one at the rear sprays out a very fine mist of water which
will cool the air and then be drained out, taking the heat with it, just as
with any other water which gets into the underground system. I claim the
prize.

That will only cool the air if the water has somewhere to evaporate to.

Would work if you combined it with loads of extra ventilation shafts.

You will end up with a very damp and not much colder underground. Also
it would probably cause everything to corrode and rot faster.

Tim