Boltar wrote:
On Jan 30, 10:30 pm, Stuart wrote:
Boltar wrote:
I've noticed the victoria line seems to be much warmer than the other
lines these days (or maybe it always has been but I've not noticed).
Is this because the trains are more frequent , or they use up more
energy on ATO , or the tunnel ventilation isn't so good , or is there
some other reason?
Always has been hotter (well as long as i've been travelling on it).

I've asked this before on here, the answer i got was that it's to do
with the fact that the Vic line is completely underground and so the
trains don't have any fresh air to cool off in except when they go to
the depot.


I'm not convinced its because its completely underground. After all
the northern line is underground all the way from mordon to east
finchley and golders green. Quite long enough for the tunnels to build
up huge amounts of heat but its not as hot as the victoria line ,
which does have the surface exit to the depot near seven sisters
anyway.

Northern Line stations strike me as being generally bigger, maybe that
helps with airflow. Also, Victoria line is the busiest (isn't it) -
people are hot (en masse).


--
Larry Lard

The address is real, but unread - please reply to the group

On Jan 31, 9:39 am, "Boltar" wrote:
On Jan 30, 10:30 pm, Stuart wrote:

Boltar wrote:
I've noticed the victoria line seems to be much warmer than the other
lines these days (or maybe it always has been but I've not noticed).
Is this because the trains are more frequent , or they use up more
energy on ATO , or the tunnel ventilation isn't so good , or is there
some other reason?

Always has been hotter (well as long as i've been travelling on it).

I've asked this before on here, the answer i got was that it's to do
with the fact that the Vic line is completely underground and so the
trains don't have any fresh air to cool off in except when they go to
the depot.

I'm not convinced its because its completely underground. After all
the northern line is underground all the way from mordon to east
finchley and golders green. Quite long enough for the tunnels to build
up huge amounts of heat but its not as hot as the victoria line ,
which does have the surface exit to the depot near seven sisters
anyway.

B2003

Yes, but I think that the longest that a Northern line train will be
below ground is less than 1 hour (from Morden to East Finchley via
Bank is 56-57 mins according to the journey planner) and trains can
have a slightly longer turn around time at Morden as there are three
platforms in the open.
On the Victoria line though, end to end time is 35 mins and the turn
around time is taken underground.

I think the important difference is the addition of cold air into the
hot trains, which only happens on the Victoria line when they goto the
depot at Northumberland Park and even then this assumes that the
trains open their doors whilst the driver changes ends. On the
Northern line, trains will stand for a few mins with their doors open
at each terminal.

It is not that the tunnels that are particularly warmer; I commute
through Stockwell and I don't think the Victoria line platforms are
generally any warmer than the Northern lines ones at the stations I
use, but the trains on the Victoria are definately warmer. On the
other hand, I think that the coolest stations (when it is hot outside)
are those on the Jubilee line extension, where there is much more
space for the heat generated by passengers to dissapate.

I don't know whther the ages of the trains on the Victoria has
anything to do with the temperature, but I would hope that the new
trains on the Victoria will be better designed for their underground
lifestyle.

"Andy" wrote in message
oups.com

I don't know whther the ages of the trains on the Victoria has
anything to do with the temperature, but I would hope that the new
trains on the Victoria will be better designed for their underground
lifestyle.

The Victoria Line trains are of similar vintage (ie, similar traction
packages) to the Piccadilly Line, but being driven automatically
probably means that they are driven harder (ie, fiercer acceleration and
braking). But I think that the 'all underground' theory is almost
certainly the right one.

On Jan 31, 9:40 am, "Boltar" wrote:
On Jan 30, 8:28 pm, "Andy" wrote:

"Boltar" wrote in message

oups.com...

I've noticed the victoria line seems to be much warmer than the other
lines these days (or maybe it always has been but I've not noticed).
Is this because the trains are more frequent , or they use up more
energy on ATO , or the tunnel ventilation isn't so good , or is there
some other reason?

B2003

The CCO (Coasting Control Override) trial might have some effect.

Whats this then?

B2003

I'm not sure if the CCO would be an issue - it's only enabled on three
stretches:

Seven Sisters - Finsbury Park (southbound only)
Oxford Circus - Green Park (southbound only)
Green Park - Victoria (southbound only)

For anyone interested this features keeps the motor going rather than
coasting once the train's reached its maximum speed. I think the heat
issue is more likely to be caused by people not opening the end of car
windows on a stock that, otherwise, has quite limited air circulation.
When the end-car windows are open at both ends I think the trains are
pretty reasonable temperature-wise

Tom

On Feb 1, 1:38 pm, "Tom Page" wrote:
For anyone interested this features keeps the motor going rather than
coasting once the train's reached its maximum speed. I think the heat

Whats the advantage of that? Wouldn't it just waste electricity and
cause excess heat as mentioned?

B2003

On 1 Feb, 14:03, "Boltar" wrote:
On Feb 1, 1:38 pm, "Tom Page" wrote:

For anyone interested this features keeps the motor going rather than
coasting once the train's reached its maximum speed. I think the heat

Whats the advantage of that? Wouldn't it just waste electricity and
cause excess heat as mentioned?

B2003

It's not exactly rocket science that if one coasts one loses speed due
to friction, so keeping the motor going allows faster journey speeds.
Of course, the benefit of this has to be weighed up against energy use
and maintenance requirements.

Tom

On Feb 1, 2:59 pm, "Tom Page" wrote:
On 1 Feb, 14:03, "Boltar" wrote:

On Feb 1, 1:38 pm, "Tom Page" wrote:

For anyone interested this features keeps the motor going rather than
coasting once the train's reached its maximum speed. I think the heat

Whats the advantage of that? Wouldn't it just waste electricity and
cause excess heat as mentioned?

B2003

It's not exactly rocket science that if one coasts one loses speed due
to friction, so keeping the motor going allows faster journey speeds.

Because of their weight and lack of rolling resistence trains tend to
lose speed far less quickly than other sorts of wheeled vehicles so it
would be interesting to see just how much speed a vic train would
loose when coasting. Of course if the track has a gradient that will
make a big difference. Surely though the logical thing would be to
have the motors cut back in when the speed had dropped by a few mph
rather than having them on constantly?

B2003

"Andy" wrote in message
oups.com...
On Jan 31, 9:39 am, "Boltar" wrote:
On Jan 30, 10:30 pm, Stuart wrote:

Boltar wrote:
I've noticed the victoria line seems to be much warmer than the other
lines these days (or maybe it always has been but I've not noticed).
Is this because the trains are more frequent , or they use up more
energy on ATO , or the tunnel ventilation isn't so good , or is there
some other reason?

Always has been hotter (well as long as i've been travelling on it).

I've asked this before on here, the answer i got was that it's to do
with the fact that the Vic line is completely underground and so the
trains don't have any fresh air to cool off in except when they go to
the depot.

I'm not convinced its because its completely underground. After all
the northern line is underground all the way from mordon to east
finchley and golders green. Quite long enough for the tunnels to build
up huge amounts of heat but its not as hot as the victoria line ,
which does have the surface exit to the depot near seven sisters
anyway.

B2003

Yes, but I think that the longest that a Northern line train will be
below ground is less than 1 hour (from Morden to East Finchley via
Bank is 56-57 mins according to the journey planner) and trains can
have a slightly longer turn around time at Morden as there are three
platforms in the open.
On the Victoria line though, end to end time is 35 mins and the turn
around time is taken underground.

I think the important difference is the addition of cold air into the
hot trains, which only happens on the Victoria line when they goto the
depot at Northumberland Park and even then this assumes that the
trains open their doors whilst the driver changes ends. On the
Northern line, trains will stand for a few mins with their doors open
at each terminal.

It is not that the tunnels that are particularly warmer; I commute
through Stockwell and I don't think the Victoria line platforms are
generally any warmer than the Northern lines ones at the stations I
use, but the trains on the Victoria are definately warmer. On the
other hand, I think that the coolest stations (when it is hot outside)
are those on the Jubilee line extension, where there is much more
space for the heat generated by passengers to dissapate.

I don't know whther the ages of the trains on the Victoria has
anything to do with the temperature, but I would hope that the new
trains on the Victoria will be better designed for their underground
lifestyle.


The Central, Northern and Jubilee lines use stock with more modern control
and braking systems, which do not generate so much heat. When the Vic stock
is replaced in 2009, it should run cooler.

The Bakerloo is also notably hot, and the Picc is at times.

Boltar wrote:
On Jan 30, 10:30 pm, Stuart wrote:
Boltar wrote:
I've noticed the victoria line seems to be much warmer than the other
lines these days (or maybe it always has been but I've not noticed).
Is this because the trains are more frequent , or they use up more
energy on ATO , or the tunnel ventilation isn't so good , or is there
some other reason?
Always has been hotter (well as long as i've been travelling on it).

I've asked this before on here, the answer i got was that it's to do
with the fact that the Vic line is completely underground and so the
trains don't have any fresh air to cool off in except when they go to
the depot.


I'm not convinced its because its completely underground. After all
the northern line is underground all the way from mordon to east
finchley and golders green. Quite long enough for the tunnels to build
up huge amounts of heat

On a cold winter's morning, the southbound Picc trains arriving at
Finsbury Park are often still really cold to the touch, even though
they've been below ground a few stops, so I think just having ANY amount
of open air section would have a significant effect on lowering the
temperature.