This question originates from a discussion of the 1880s and 1890s
plans in Britain to build a Channel Tunnel between England and France.
Whilst latterly electric and pneumatic designs were looked at, the
original designs were for tunnels to house steam locomotives. In the
1890s there were also similar plans for Alaska-Siberia which did not
come to anything. The question is not about the logistics of tunnel
building which seems to have been a given, albeit a very expensive
one. I really need to know how steam locomotives would have dealt with
the great distance under water.
Other long tunnels have air flues and ventilation that is just not
availbale underwater, regardless of fantasy novels which have huge
smoke stacks leading to artificial islands. As the plans DID exist in
the 1880s and 1890s and there were also substantial tunnels elsewhere,
what is the intended solution ?
Specifically, would it be
- a ventilation system
- better smoke hoods on the locomotives
- neither, but sealed locomotives and carriages so the smoke and steam
is not a hazard ?
Or a mix of all three ?
Would the plans require a switch of locomotives at either end of the
tunnel ?
etc
I hope this is clear... Its about the practicalities of running steam
locomotives deep underground where no ventilation to the surface is
possible, and drawing on the historical examples for explanation where
possible
Thanks
wolvies, lol |
Request for Question Clarification by
pafalafa-ga
on
01 Sep 2003 17:04 PDT
Helo Wolvies,
Based on my reading of a fairly extensive discussion of tunnel
ventilation from a 1911, it seems that mechanical ventilation systems
were the option of choice for long tunnels (which were common in
mountains, where the presence of the mountain mass also made
ventilation shafts impractical).
Also, the innovation of digging two-bore tunnels that were
interconnected also seemed to greatly facilitate ventilation, as the
unused bore served as a sort of giant exhaust tube.
I would post this link as an answer if the document was complete with
illustrations. Unfortunately, it was put online as a text only
document, and the ventilation discussion is just too hard for me to
follow without being able to refer to the missing diagrams. I didn't
want to presume this as a legit answer, with such important pieces of
the article missing.
Any how, here it is:
http://19.1911encyclopedia.org/T/TU/TUNNEL.htm
Do a Ctrl-F search for "ventilation" and it should take you to the
best spots in the article.
Let me know if this helps.
pafalafa-ga
|
Request for Question Clarification by
leli-ga
on
02 Sep 2003 02:03 PDT
Hi wolvies
Evidence given to a committee in 1881 with representatives from the
Admiralty, the Board of Trade and the War Office shows that a twin
tunnel scheme was the plan in mind. This plan is not elaborated
anywhere online as far as I can tell - as you will know, far more
attention was given to the speed of flooding the tunnel if a foreign
army should enter it - but one of the dominant figures in proposals
for a Channel Tunnel said he "expect[ed] the two Tunnels [would]
ventilate each other." (He is quoted in a contemporary pamphlet
containing the text of an 1883 lecture on the subject, with page
references to committee reports about the Channel Tunnel.)
I have found other references to this idea for the Tunnel and also a
couple of websites saying that the late Victorian planners proposed to
use non-steam trains. Also, there had been some quite serious plans
for your "fantasy" air shafts ;)
There was another twin tunnel proposal for the Channel railway in the
early twentieth century but I haven't found any details of the
Alaskan-Siberian scheme of the same date, or any other tunnel of
comparable length.
I'm not sure how much you need in the way of engineering detail or
historical examples. I found no evidence of plans to use "better smoke
hoods on the locomotives", "sealed locomotives and carriages", or
ventilation fans.
With all that in mind, can I ask you, as pafalafa did, to clarify what
level of detail you need in an answer?
It's nice to see you round these parts again - you always have such
fascinating questions for us.
Leli
|
Clarification of Question by
wolvies-ga
on
02 Sep 2003 03:34 PDT
Thank you to the 2 researchers extraordinaire for this extremely good
work so far :) I guess in order for it to be 'answer' I need to be
able to visualise from it how it would work, in order to be able to
visualise the trains as they run through. And they need to be the
plans relating just to steam locomotives; I've looked at the
compressed-air and electric versions, but its the steam traction that
I found myself failing to understand.
Where the double bore is concerned, is this meaning that only one
tunnel would be in use for the trains (2 tracks ?) and the other only
a ventilation system ? One might suppose there would be tracks laid on
the other for emergency etc
If this can be brought into a coherent whole I would be happy to call
it an answer. Thanks again as always
wolvies, lol
|
Request for Question Clarification by
pafalafa-ga
on
02 Sep 2003 12:23 PDT
My understanding is that the two-bore tunnel design had two
operational tunnels, but presumably, they didn't both have trains in
them at the same time. Because the tunnels are interconnected, the
tunnel not in use at any given time becomes the de facto exhaust bore
for the tunnel that is in use.
On the other hand, a set of plans from 1875 shows a decidedly
single-bore tunnels, with some "mini bores" set into the tunnel "roof"
to act as air vents (they appear to be labelled air valves on the
diagram):
http://www.pro.gov.uk/virtualmuseum/maingalleries/world/channel/channel.htm
If you have a moment, let me know if the diagram and/or the
encyclopedia article were helpful to you in providing information. It
seems that, with Leli's and my postings, you might have the
information you need. But if something specific seems to be missing,
let us know so we can look into it for you.
paf
|
Clarification of Question by
wolvies-ga
on
03 Sep 2003 09:01 PDT
Sure, if you can combine all the info, including some from that
interesting 1911 encyclopedia article that would do as an answer. Of
course any additional info, or locomotive designs would be welcome - a
schematic of the one with the bag would be intriguing !
All the best
Wolvies
|
