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Post by chris on May 21, 2005 17:53:09 GMT
Where do those strange winds come from and why is different places on the tube hotter than others. There are even mysterious drips on deep level stations sometimes. I've never understood this and put it down to;
a) Trains rushing in and out
b) Ventilation/faning systems
c) My ever growing insanity
Oh, and on a different note but still with the same inquisative mind, why do business people run around like the trains are never to be seen? i mean, there's another one in 2 or 3 minutes for gods sake! (This baffled my Australian cousins and they found it highly amusing they ran to a timetable)
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Deleted
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Post by Deleted on May 21, 2005 18:37:33 GMT
Where do those strange winds come from and why is different places on the tube hotter than others. There are even mysterious drips on deep level stations sometimes. I've never understood this and put it down to; a) Trains rushing in and out b) Ventilation/faning systems c) My ever growing insanity Assuming it's the same as Liverpool, where the decline in manufacturing has caused the water table to rise, making the Merseyrail system very wet indeed, then I'd put it down to rising water table. There are also many underground streams and leaky pipes below London (well underground streams wouldn't be above ground would they? :  . The wind is caused by the 'piston effect' of trains moving through tunnels. |
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Post by Admin Team on May 22, 2005 19:34:03 GMT
Strange winds? That's probably due to the driver having had too many baked beans with his grub!  My understanding is (from my limited knowledge of those nasty deep tube lines) is that it's the piston in cylinder effect of the tube stocks pushing air along in front of them that causes the rushes of air. Much of the heat is generated by the resistance equipment in te trains - including the brakes etc. Water is a combination of the leaks in the water mains and the seepages through poorly pointed brickwork. As to the point about 'suits' running around as if there will never be another train - who knows! I chat to the tourists often whilst waiting to pick up, and if they don't know the Underground, most marvel at a two minute service. But to the daily commuters, a three minute wait is SOOOOOOOOOOOOOOOOOOOOOO inconvenient! |
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Phil
In memoriam
RIP 23-Oct-2018
Posts: 9,473
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Post by Phil on May 23, 2005 9:48:50 GMT
As to the point about 'suits' running around as if there will never be another train - who knows! But for those who have had to travel during the times of poor reliability there often wasn't! From a consumer point of view there is nothing to gee one up down the stairs like the sign 'severe delays at........' and then seeing a train coming in, well........ But otherwise? Perhaps it is their only way of getting exercise during the day! |
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Post by citysig on May 23, 2005 18:26:12 GMT
The weather - there was a small study somewhere a while ago (it may still be ongoing but can't remember who by - I am sure someone with more time than me will find it). The tube actually plays host to a mini environment of it's own. The heat and wind thing is actually quite random and not down to just the trains or equipment. The unique layout of platforms, passages and entrances to stations, forms some very unique weather patterns. I have been caught in what can only be described as a small gale in the SSL side of King's Cross station - even though at the time there were no trains serving that part of the station! As for those business people. They simply do not trust us when we tell them there will be another train along in a minute. Mind you, when you look at some of those suited individuals, would you trust them? So the feeling is at least mutual ;D |
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Post by yellowsignal on May 23, 2005 19:08:48 GMT
The dripping is most likely caused by rising watertable and leaking pipes (water mains, sewers). It's not always because the tunnel lining is bad, in some cases it's wise to have water enter the tunnel in a controlled fashion, this keeps waterpressure from builing up. Waterpressure can be a big factor, especially in deep tunnels. I am sure there are a lot of pumps in the undergound system.
The channel tunnel has a porous lining in places, pumps are used to collect and move the water to the surface.
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