> On Sat, 9 Aug 2008, Edward Cowling London UK wrote:
>

>> In message news.demon.co.uk>, John Rowland
>> journeyflow.spamspam.demon.co.uk> writes

>>> Edward Cowling London UK wrote:

>>>> After another grim morning on Friday, I wonder why the ventilation on
>>>> the Victoria Line is so bad ? If you change to the Piccadilly at
>>>> Finsbury Park it's like entering a different world. So if the Picc
>>>> Line can stay reasonably fresh why can't the Vic Line ? Even with
>>>> the trains at full hurtle little air seems to move about the carriage.

>>>
>>> The Victoria Line is completely underground, except for the depot. The
>>> Picc
>>> has several open air sections.

>>
>> Which makes it sound unlikely the refurb and new trains will help.

>
> They should do. Firstly, they'll have regenerative braking, which means
> less of the train's kinetic energy will be turned into heat, so the
> tunnels won't get as hot in the first place. Secondly, i understand
> they've been designed with better ventilation: what matters is the
> temperature on board the train, and this has got as much to do with
> airflow between the train and tunnel as with the temperature in the
> tunnel itself. I posted a link to a paper on some research about this a
> few weeks ago; i don't have it to hand, but i seem to remember that
> better ventilation could buy a few degrees of coolness.