1 bar is not the sea to drink ... the vehicle must have thick walls like a compressed air tank of 1 bar to maintain an ambient pressure of 1 bar in a vacuum the problem is not there
for aerodynamics you shouldn't do things by halves ... make a mediocre vacuum which requires a much larger tunnel than the vehicle ... blah ...
as much to make a real vacuum sufficiently pushed to have all the advantages
that's why I only see the well welded steel tube like a gas pipeline
concrete tunnel without interest ... too leaky
Vacuum transport: the key to long distance transport?
- chatelot16
- Econologue expert
- posts: 6960
- Registration: 11/11/07, 17:33
- Location: Angouleme
- x 264
chatelot16 wrote:1 bar is not the sea to drink
Fully agree.
chatelot16 wrote:as much to make a real vacuum sufficiently pushed to have all the advantages
This has no consequence on the choice of tube material: the difference in mechanical force is marginal.
The residual pressure level does not change much the problem of the ratio of the tube and vehicle sections: but I agree that making the vacuum at lower cost is always better than letting rub on the edges :-)
chatelot16 wrote:that's why I only see the well welded steel tube like a gas pipeline
It is discussed in terms of mass and price, so also in terms of investment and gray energy.
A HDPE tube, it is delivered in great length, it is welded very easily, including in the event of a leak, and it is pierced and cut as easily, for a need of security ...
chatelot16 wrote:concrete tunnel without interest ... too leaky
I have no clear-cut opinion between steel and plastic, but the mass and the rigidity of the concrete seem to me in fact unsuitable. Except possibly to cross a mountain in a tunnel, which protects the transport tube and allows access to it?
0 x
See you soon !
Christophe wrote:the metroswiss project is public transport
A smaller tube is also public transport, but in series
The flow depends on the distance between the vehicle, multiplied by the speed. Light vehicles can be very close, and the vacuum allows very high speed.
It is the speed of the switches that will determine the distance between vehicles of different destination: if there is a technological problem to solve, it is of course the high-speed switches.
We can do without it, but we lose a lot of energy (unnecessary stops) and speed.
you would need a central hanging rail, and for switches, 2 rails of different height or arranged one on the right, the other on the left, with 2 hanging systems, which are selected according to the direction. All this at full speed :-) There is work ...
0 x
See you soon !
- Obamot
- Econologue expert
- posts: 28725
- Registration: 22/08/09, 22:38
- Location: regio genevesis
- x 5538
The "expensive" solution of Swissmetro would rely on two completely separate conduits ... It's not wrong: question of safety at 500 km / h, it is better that there is never anything in front. I do not think there were any planned switches on the route but two completely separate lines (each with two completely separate return hoses for each line), unless I am mistaken.
0 x
And it's even easier with small tubes.
There is a representation on this site: http://www.et3.com/gallery.asp
They leave on vehicles for 6 passengers, 2 front.
I would rather go to one front :-)
We can also consider 4 tubes, 2 for each direction.
And on 2 tubes in the same direction, we can consider 1 tube for the long distance, and the second tube for a more local service.
There is a representation on this site: http://www.et3.com/gallery.asp
They leave on vehicles for 6 passengers, 2 front.
I would rather go to one front :-)
We can also consider 4 tubes, 2 for each direction.
And on 2 tubes in the same direction, we can consider 1 tube for the long distance, and the second tube for a more local service.
0 x
See you soon !
I had heard of an even crazier idea based on this principle: transcontinental tunnels under vacuum (or low pressure).
Over long distances, managing entrances and exits is simple with airlock systems. By digging tubes, no big problems of pressure resistance.
The end of the end: over these great distances, the tunnel which goes in a straight line no longer follows exactly an iso-gravity line. Result: on the half of the journey, the train is not supplied, it descends following the (slight) slope. The second half, launched on its inertia, it goes up the slope. It only takes a little energy to compensate for the remaining rolling friction.
It is therefore a train which works by gravity!
There must have been studies on it. I wonder if I haven't read a news from Asimov or clarke on this system ...
The infrastructure is heavy, but the operating energy must be low, surely much lower than the consumption of journeys by intercontinental aircraft!
Over long distances, managing entrances and exits is simple with airlock systems. By digging tubes, no big problems of pressure resistance.
The end of the end: over these great distances, the tunnel which goes in a straight line no longer follows exactly an iso-gravity line. Result: on the half of the journey, the train is not supplied, it descends following the (slight) slope. The second half, launched on its inertia, it goes up the slope. It only takes a little energy to compensate for the remaining rolling friction.
It is therefore a train which works by gravity!
There must have been studies on it. I wonder if I haven't read a news from Asimov or clarke on this system ...
The infrastructure is heavy, but the operating energy must be low, surely much lower than the consumption of journeys by intercontinental aircraft!
0 x
-
- Moderator
- posts: 79113
- Registration: 10/02/03, 14:06
- Location: Greenhouse planet
- x 10972
Not really understood this case of non iso gravity ?? I can see what you mean in relation to a small sphere but ... it doesn't seem too applicable to me on a planet scale ...
Ah well, here it is already more credible than the underground underground vacuum!
Is there a demonstrator planned? Because for the moment it is only computer graphics ... apparently ...
By cons must not be claustrophobic
bernardd wrote:There is a representation on this site: http://www.et3.com/gallery.asp
Ah well, here it is already more credible than the underground underground vacuum!
Is there a demonstrator planned? Because for the moment it is only computer graphics ... apparently ...
By cons must not be claustrophobic
0 x
Do a image search or an text search - Netiquette of forum
- Obamot
- Econologue expert
- posts: 28725
- Registration: 22/08/09, 22:38
- Location: regio genevesis
- x 5538
If this happens, you can be sure that in the long term there will be two offers: one with cabins with pseudo picture windows and the other economical without opening. I see it like that, we know how to make windshields with a plastic sheet in it, it could be on the same principle and very well withstand the pressure especially if it is small windows of a small circular section on 50cm ... It would be barely more expensive for the tubes! A window of 50cm2 every 6m to have the impression of a continuous scrolling (at 500 km / h it would be ~ 24 images / second)
Unless they choose flexible oled screens to put on the walls ... but where would the camera be fixed?
[Edit:] basically I say that because for a project to work, it must be successful with the public. If the public asks for windows there will certainly be ... to be seen. Notice that in a tunnel ...
Unless they choose flexible oled screens to put on the walls ... but where would the camera be fixed?
[Edit:] basically I say that because for a project to work, it must be successful with the public. If the public asks for windows there will certainly be ... to be seen. Notice that in a tunnel ...
0 x
Christophe wrote:Not really understood this case of non iso gravity ?? I can see what you mean in relation to a small sphere but ... it doesn't seem too applicable to me on a planet scale ...
Draw a circle, with a straight line that crosses it between 2 points of the circumference :-) Relative to the center, the line goes down first, then goes up afterwards!
But we must be able to be very hot: we know very little about the interior of the earth, I prefer to avoid ...
Intercontinental transport is planned:
"high tech systems for continental and intercontinental transport up to 4,000 mph or more. For greater detail see technology section." I read 2h for a NewYork-Beijing ...
Christophe wrote:bernardd wrote:There is a representation on this site: http://www.et3.com/gallery.asp
Ah well, here it is already more credible than the underground underground vacuum!
Is there a demonstrator planned? Because for the moment it is only computer graphics ... apparently ...
Didn't you see the link in the first post? I was on the same idea, then I found this site which draws better than me :-) But it does not give calculations and seems access on the commercial, with licenses. I prefer free engineering ...
0 x
See you soon !
-
- Similar topics
- Replies
- views
- Last message
-
- 20 Replies
- 19740 views
-
Last message by moinsdewatt
View the latest post
17/06/20, 23:40A subject posted in the forum : New transport: innovations, engines, pollution, technologies, policies, organization ...
-
- 77 Replies
- 36354 views
-
Last message by The shadow
View the latest post
14/07/15, 12:13A subject posted in the forum : New transport: innovations, engines, pollution, technologies, policies, organization ...
-
- 39 Replies
- 17499 views
-
Last message by chatelot16
View the latest post
29/08/12, 15:09A subject posted in the forum : New transport: innovations, engines, pollution, technologies, policies, organization ...
-
- 9 Replies
- 7845 views
-
Last message by sen-no-sen
View the latest post
18/11/11, 12:49A subject posted in the forum : New transport: innovations, engines, pollution, technologies, policies, organization ...
-
- 0 Replies
- 3049 views
-
Last message by Christophe
View the latest post
28/10/11, 09:51A subject posted in the forum : New transport: innovations, engines, pollution, technologies, policies, organization ...
Back to "New transport: innovations, engines, pollution, technologies, policies, organization ..."
Who is online ?
Users browsing this forum : No registered users and 197 guests