London Banter - View Single Post - Crossrail Elizabeth Line trainset unveiled

[email protected] · July 31st 16, 07:45 PM posted to uk.railway,uk.transport.london

On Sun, 31 Jul 2016 19:58:59 +0100, Basil Jet
wrote:

On 2016\07\31 18:25, wrote:
On Sun, 31 Jul 2016 13:19:28 +0100, Colin Reeves
wrote:

On 30/07/2016 20:50, D A Stocks wrote:

Eurotunnel manage something like that in the Channel Tunnel, and they
don't have stations every few hundred yards where they can remove the
excess heat generated.

But, the holes that the trains run through are vastly larger than tube
tunnels - and they have the service tunnel as well. Much more scope for
cooling if needed!

There are doors to the service tunnel and it is at higher pressure in
case of fire so it doesn't really play a part in heat removal. There
are air shafts linking the two running tunnels and there are cold
water pipes in each tunnel to provide cooling.

Are the pipes supposed to transfer heat to the rock around the tunnel or
out the ends of the tunnel? I can't imagine the latter working very well
in a 50km tunnel.

Out of the tunnel, there's a cooling plant at each end. I guess it's
configured as 25 km out and return rather than all the way through.
The plants supply water at 4 C, no idea of the return temperature.