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| Tim Walters |
 Posted: Tue Sep 12, 2006 8:15 am |
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Guest
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What are the technical problems in running maglev trains at near the speed
of sound?
Thanks in advance for any input.
Tim |
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| Sorcerer |
| Posted: Tue Sep 12, 2006 9:20 am |
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Guest
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"Tim Walters" <timwalters@terraform.es> wrote in message
news:a2qff.tku.17.1@news.alt.net...
| What are the technical problems in running maglev trains at near the speed
| of sound?
|
| Thanks in advance for any input.
|
| Tim
Apart from the same problems associated with aircraft, do you mean?
One that comes instantly to mind is tunnels. Pushing air ahead through
a tunnel at the speed of sound would require an enormous amount
of energy, and the drag doesn't help as the air refills the tunnel behind
the train. However, that can be overcome by slowing the train solely
for the tunnels. The next problem is curves. Experiments were
carried out in Britain that allowed trains to tilt at high speed, but
were scrapped.
Then there is the social problem of sonic booms, which is really
a technical problem.
People would not like having broken windows everyday, and they'd
be much closer to the source so medical problems as well with burst
ear drums.
Concorde was banned from flying supersonic over land for that
reason or it would be flying New York to Los Angeles at 40,000 ft
today instead of being scrapped, and a sonic boom from 40,000 ft
is merely a minor nuisance. You have two chances of ever seeing it
happen except as an experiment on the Great Salt Lake or similar
remote flat surface with a straight path, fat and slim, and investors
would be fools to put money into it.
Androcles |
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| Tim Walters |
| Posted: Tue Sep 12, 2006 9:52 am |
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Guest
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What I was thinking of was a maglev railway built offshore. There wouldn't
be any tunnels and, moving at less than the speed of sound, there wouldn't
be any sonic boom.
(Though, while we're on the subject, why not put the monorail inside a tube,
suck the air out ahead of the trains, and run them through at Mach 2?)
I know maglev trains use a lot of power, but wouldn't there be a plentiful
supply of energy from wind, waves and tide?
I notice that most existing maglev trains go up to speeds of around 500 kph.
I wondered if there was some technical reason why they don't go faster.
Tim
"Sorcerer" <Headmaster@hogwarts.physics_b> wrote in message
news:%BxNg.50512$H03.7600@fe3.news.blueyonder.co.uk...
[quote:685767f1c4]
"Tim Walters" <timwalters@terraform.es> wrote in message
news:a2qff.tku.17.1@news.alt.net...
| What are the technical problems in running maglev trains at near the
speed
| of sound?
|
| Thanks in advance for any input.
|
| Tim
Apart from the same problems associated with aircraft, do you mean?
One that comes instantly to mind is tunnels. Pushing air ahead through
a tunnel at the speed of sound would require an enormous amount
of energy, and the drag doesn't help as the air refills the tunnel behind
the train. However, that can be overcome by slowing the train solely
for the tunnels. The next problem is curves. Experiments were
carried out in Britain that allowed trains to tilt at high speed, but
were scrapped.
Then there is the social problem of sonic booms, which is really
a technical problem.
People would not like having broken windows everyday, and they'd
be much closer to the source so medical problems as well with burst
ear drums.
Concorde was banned from flying supersonic over land for that
reason or it would be flying New York to Los Angeles at 40,000 ft
today instead of being scrapped, and a sonic boom from 40,000 ft
is merely a minor nuisance. You have two chances of ever seeing it
happen except as an experiment on the Great Salt Lake or similar
remote flat surface with a straight path, fat and slim, and investors
would be fools to put money into it.
Androcles
[/quote:685767f1c4] |
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| Guest |
| Posted: Tue Sep 12, 2006 11:31 am |
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Tim Walters wrote:
[quote:6c2d1e1624]What I was thinking of was a maglev railway built offshore. There wouldn't
be any tunnels and, moving at less than the speed of sound, there wouldn't
be any sonic boom.
(Though, while we're on the subject, why not put the monorail inside a tube,
suck the air out ahead of the trains, and run them through at Mach 2?)
I know maglev trains use a lot of power, but wouldn't there be a plentiful
supply of energy from wind, waves and tide?
I notice that most existing maglev trains go up to speeds of around 500 kph.
I wondered if there was some technical reason why they don't go faster.
Tim
"Sorcerer" <Headmaster@hogwarts.physics_b> wrote in message
news:%BxNg.50512$H03.7600@fe3.news.blueyonder.co.uk...
"Tim Walters" <timwalters@terraform.es> wrote in message
news:a2qff.tku.17.1@news.alt.net...
| What are the technical problems in running maglev trains at near the
speed
| of sound?
|
| Thanks in advance for any input.
|
| Tim
Apart from the same problems associated with aircraft, do you mean?
One that comes instantly to mind is tunnels. Pushing air ahead through
a tunnel at the speed of sound would require an enormous amount
of energy, and the drag doesn't help as the air refills the tunnel behind
the train. However, that can be overcome by slowing the train solely
for the tunnels. The next problem is curves. Experiments were
carried out in Britain that allowed trains to tilt at high speed, but
were scrapped.
Then there is the social problem of sonic booms, which is really
a technical problem.
People would not like having broken windows everyday, and they'd
be much closer to the source so medical problems as well with burst
ear drums.
Concorde was banned from flying supersonic over land for that
reason or it would be flying New York to Los Angeles at 40,000 ft
today instead of being scrapped, and a sonic boom from 40,000 ft
is merely a minor nuisance. You have two chances of ever seeing it
happen except as an experiment on the Great Salt Lake or similar
remote flat surface with a straight path, fat and slim, and investors
would be fools to put money into it.
Androcles
[/quote:6c2d1e1624]
I once attended a maglev conference and one of the biggest obstacles to
really high speed maglev is the radius of curvature on curves to keep
the g forces down to something reasonable. This made the curves REALLY
LARGE exacerbating the already absurd costs of a couple billion
dollars/mile. For that sort of cost, development of high speed
conventional rail is easy. Maglev trains are a solution in search of a
problem. |
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| Sorcerer |
| Posted: Tue Sep 12, 2006 12:02 pm |
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Guest
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"Tim Walters" <timwalters@terraform.es> wrote in message
news:a3064.jn1.17.1@news.alt.net...
| What I was thinking of was a maglev railway built offshore. There wouldn't
| be any tunnels and, moving at less than the speed of sound, there wouldn't
| be any sonic boom.
Then you've given up your first requirement, "near the speed of sound".
Corrosion becomes a problem. Salt water is nasty, ship fittings are
stainless
steel these days.
| (Though, while we're on the subject, why not put the monorail inside a
tube,
| suck the air out ahead of the trains, and run them through at Mach 2?)
Then you need powerful fans, which kinda makes jet engines on planes
a better deal.
| I know maglev trains use a lot of power, but wouldn't there be a plentiful
| supply of energy from wind, waves and tide?
Only if you harness it first. People are working in that.
http://tinyurl.com/k6kxp
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| I notice that most existing maglev trains go up to speeds of around 500
kph.
| I wondered if there was some technical reason why they don't go faster.
|
| Tim
Sure there is. I've given you a couple of reasons, curves and tunnels.
There is no electrical or magnetic reason, if that is what you are asking.
The thing is, son, almost anything is possible, but the objective is
to move people from A to B in a cost-effective manner. That includes
construction, maintenance, running costs, speed, energy... in short,
engineering... and then capital investment.
What do you want a train for, anyway? Why not rail buses, taxies and
trucks operated by computers? Goods could be shipped overnight to
anywhere without a driver, it takes large trucks off the roads, all we need
is more rail in cities. We have the main arteries which are currently
under-used, built with steam and safety in mind, and we have the technology.
Each vehicle could communicate with a central computer via cell phone
and know where it is from GPS. Complex as a system, simple as an idea.
Androcles
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| "Sorcerer" <Headmaster@hogwarts.physics_b> wrote in message
| news:%BxNg.50512$H03.7600@fe3.news.blueyonder.co.uk...
| >
| > "Tim Walters" <timwalters@terraform.es> wrote in message
| > news:a2qff.tku.17.1@news.alt.net...
| > | What are the technical problems in running maglev trains at near the
| speed
| > | of sound?
| > |
| > | Thanks in advance for any input.
| > |
| > | Tim
| >
| > Apart from the same problems associated with aircraft, do you mean?
| > One that comes instantly to mind is tunnels. Pushing air ahead through
| > a tunnel at the speed of sound would require an enormous amount
| > of energy, and the drag doesn't help as the air refills the tunnel
behind
| > the train. However, that can be overcome by slowing the train solely
| > for the tunnels. The next problem is curves. Experiments were
| > carried out in Britain that allowed trains to tilt at high speed, but
| > were scrapped.
| > Then there is the social problem of sonic booms, which is really
| > a technical problem.
| > People would not like having broken windows everyday, and they'd
| > be much closer to the source so medical problems as well with burst
| > ear drums.
| > Concorde was banned from flying supersonic over land for that
| > reason or it would be flying New York to Los Angeles at 40,000 ft
| > today instead of being scrapped, and a sonic boom from 40,000 ft
| > is merely a minor nuisance. You have two chances of ever seeing it
| > happen except as an experiment on the Great Salt Lake or similar
| > remote flat surface with a straight path, fat and slim, and investors
| > would be fools to put money into it.
| >
| > Androcles
| >
| >
| >
| >
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| Sorcerer |
| Posted: Tue Sep 12, 2006 12:44 pm |
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Guest
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<dbohara@mindspring.com> wrote in message
news:1158071518.764143.186970@b28g2000cwb.googlegroups.com...
|
| Tim Walters wrote:
| > What I was thinking of was a maglev railway built offshore. There
wouldn't
| > be any tunnels and, moving at less than the speed of sound, there
wouldn't
| > be any sonic boom.
| >
| > (Though, while we're on the subject, why not put the monorail inside a
tube,
| > suck the air out ahead of the trains, and run them through at Mach 2?)
| >
| > I know maglev trains use a lot of power, but wouldn't there be a
plentiful
| > supply of energy from wind, waves and tide?
| >
| > I notice that most existing maglev trains go up to speeds of around 500
kph.
| > I wondered if there was some technical reason why they don't go faster.
| >
| > Tim
| >
| >
| >
| > "Sorcerer" <Headmaster@hogwarts.physics_b> wrote in message
| > news:%BxNg.50512$H03.7600@fe3.news.blueyonder.co.uk...
| > >
| > > "Tim Walters" <timwalters@terraform.es> wrote in message
| > > news:a2qff.tku.17.1@news.alt.net...
| > > | What are the technical problems in running maglev trains at near the
| > speed
| > > | of sound?
| > > |
| > > | Thanks in advance for any input.
| > > |
| > > | Tim
| > >
| > > Apart from the same problems associated with aircraft, do you mean?
| > > One that comes instantly to mind is tunnels. Pushing air ahead through
| > > a tunnel at the speed of sound would require an enormous amount
| > > of energy, and the drag doesn't help as the air refills the tunnel
behind
| > > the train. However, that can be overcome by slowing the train solely
| > > for the tunnels. The next problem is curves. Experiments were
| > > carried out in Britain that allowed trains to tilt at high speed, but
| > > were scrapped.
| > > Then there is the social problem of sonic booms, which is really
| > > a technical problem.
| > > People would not like having broken windows everyday, and they'd
| > > be much closer to the source so medical problems as well with burst
| > > ear drums.
| > > Concorde was banned from flying supersonic over land for that
| > > reason or it would be flying New York to Los Angeles at 40,000 ft
| > > today instead of being scrapped, and a sonic boom from 40,000 ft
| > > is merely a minor nuisance. You have two chances of ever seeing it
| > > happen except as an experiment on the Great Salt Lake or similar
| > > remote flat surface with a straight path, fat and slim, and investors
| > > would be fools to put money into it.
| > >
| > > Androcles
| > >
| > >
| > >
| > >
|
| I once attended a maglev conference and one of the biggest obstacles to
| really high speed maglev is the radius of curvature on curves to keep
| the g forces down to something reasonable. This made the curves REALLY
| LARGE exacerbating the already absurd costs of a couple billion
| dollars/mile. For that sort of cost, development of high speed
| conventional rail is easy. Maglev trains are a solution in search of a
| problem.
Yep...
Androcles. |
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| G=EMC^2 Glazier |
| Posted: Tue Sep 12, 2006 8:07 pm |
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Tim Maybe being at ground level,an the air being denser might be a
problem. Planes creating a sonic boom can cause a million dollars worth
of damage breaking building windows an usually the rear windows of cars
flying to low Not sure what the limit speed is for a "linear
induction motor" The coils on the train generate a magnetic field in
which the poles shift along the train. This field induces electric
currents in the reaction rail,which in turn generates its own field.
Thus the two fields interact so that the shifting field pulls the
"floating"(no friction) along the track. Tricky part I see with this is
how fast the poles shift,and that could be its speed limit. Reality
is I have a curtain that uses an induction motor. They have been around
for about 85 years. Your car starting motor(Bendix) is using an
induction motor,and a few years go this guy used it to make a very
fast(fastest in the world machine gun) Feel like typing so I'll add
this a mouse was levitated by a magnetic field That proves there is
some magnetizim in just about everything Go figure Bert. |
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| hanson |
| Posted: Tue Sep 12, 2006 8:29 pm |
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Guest
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"G=EMC^2 Glazier" <herbertglazier@webtv.net> wrote in message
news:21480-45073D95-773@storefull-3333.bay.webtv.net...
[quote:ed12d7ed75]Reality is I have a curtain that uses an induction motor. They have
been around for about 85 years.
Feel like typing so I'll add this a mouse was levitated by a
magnetic field That proves there is some magnetizim in just
about everything Go figure Bert.
[hanson][/quote:ed12d7ed75]
..... AHAHAHAHA... keep on figuring, Herbie... ahahaha...
especially in view of your 85 year old curtains (ever washed
them?) with your levitated mouse and your proofs...
Now then Herbie, keep feeling like typing and keep doing
so until you have answered the levitating question in here:
http://groups.google.com/group/sci.physics/msg/c63950ab858592a7
Don't get tired on me now Herbie, or I will ask you why.
ahahaha... ahahahanson |
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| G=EMC^2 Glazier |
| Posted: Wed Sep 13, 2006 9:33 am |
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Hanson I could never get tired of you. You are a joke. You make me
laugh. Bert |
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| G=EMC^2 Glazier |
| Posted: Sun Sep 17, 2006 4:50 pm |
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Meglev Trains would work best in a tunnel. Have the air in front very
dry low density.If the trains body fitted in snugly,and the walls of the
tunnel were electromagnetic the train would act like a particle in an
accelerator. That would make 10,000 mph easy. Go Figure Bert |
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| editor@netpath.net |
| Posted: Sun Sep 17, 2006 8:13 pm |
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Guest
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I suggest studying the history of "Skybus" - the Pittsburgh area's
ill-fated attempt around 1970 to develop an elevated monorail system of
rapid transit for that area. It just got further and further over
budget, further and further behind schedule, and increasingly obviously
impractical. Its impracticality was obvious to almost anyone with
mechanical skill. Nonetheless, very few politicians would stand up to
the "we can't cut it now that we have so much invested" argument -
particularly as so many big Pittsburgh corporations were major
contractors on Skybus, which eventually went as far as a demonstration
project at South Park. Eventually - after a fortune down the rathole -
it was canceled.
No $4 to park! No $6 admission! http://www.INTERNET-GUN-SHOW.com |
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| Sorcerer |
| Posted: Sun Sep 17, 2006 9:09 pm |
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Guest
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<editor@netpath.net> wrote in message
news:1158534788.912976.34520@i3g2000cwc.googlegroups.com...
| I suggest studying the history of "Skybus" - the Pittsburgh area's
| ill-fated attempt around 1970 to develop an elevated monorail system of
| rapid transit for that area. It just got further and further over
| budget, further and further behind schedule, and increasingly obviously
| impractical. Its impracticality was obvious to almost anyone with
| mechanical skill. Nonetheless, very few politicians would stand up to
| the "we can't cut it now that we have so much invested" argument -
| particularly as so many big Pittsburgh corporations were major
| contractors on Skybus, which eventually went as far as a demonstration
| project at South Park. Eventually - after a fortune down the rathole -
| it was canceled.
|
| No $4 to park! No $6 admission! http://www.INTERNET-GUN-SHOW.com
Yes, well... Pittsburgh's Mt. Washington has a funicular railway... terrain
is a pretty good deterrent to maglev trains and monorails. |
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| Jeff…Relf |
| Posted: Sun Sep 17, 2006 10:42 pm |
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Hi George_Orwell and Ha_Ha_Hanson,
Collectively, the U.S. and its partners ( including the IMF ! ) are
The real Devil_God of the Middle East... making Allah and Jehovah look small.
Isreal and Saudi Arabia are under their thumb, controlling the region.
The U.S. and it's partners won WWII,
gaining control of the oil in the " Holy Land ".
They collect rent in the form of oil ( which they lust for like junkies ).
They lay down the law and evict ( or kill ) whoever they please. |
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| hanson |
| Posted: Mon Sep 18, 2006 2:12 pm |
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Guest
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ahahahaha... ahahaha... AHAHAHA... ahahaha.. AHAHA...
ahahaha ... But you do help me , very effectively so, Jeff.
After all, Jeff, proselytizing is in your blood. You have the
needed background. Your role model, Glaser, the Zionist bigot,
and you, Jeff, as his evangelical slave, are perfect vehicles.
"Jeff.Relf" <Jeff_Relf@Yahoo.COM> a notorious child-support
delinquent and long term welfare recipient wrote in message
news:Jeff_Relf_2006_Sep_18_PoH1@Cotse.NET...
[quote:a070555d95]I'm not helping you spread your oft-repeated question,
I'm just answering it everytime.
[hanson][/quote:a070555d95]
ahahaha... But and yes you do. You do not only spread it but
you are a cause and reason for disseminating the question
in my post which was:
== What good or benefit has come in return to the American
taxpayers from Israel for all that tax money that came off the
tables from poor American families?"
== "...the USA, which is paying to Israel 3-7 Billion $$$US tax
money each year for the last 60 years & an equal $ amount
to the muslim ass-venters to placate and pacify them so that
they don't continue to kick Jew ass, does beg the question:
==== What are all these BILLIONS of US tax-payer dollars
buying the American public, besides continuous terrorism,
mayhem and war where Jews are being connected to or
involved in ?
http://groups.google.com/group/sci.physics/msg/5a611859fb015d7a
ahahaha... ahahahanson |
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| tadchem |
| Posted: Sat Sep 30, 2006 7:19 am |
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G=EMC^2 Glazier wrote:
[quote:5cffa51d9f]Meglev Trains would work best in a tunnel. Have the air in front very
dry low density.If the trains body fitted in snugly,and the walls of the
tunnel were electromagnetic the train would act like a particle in an
accelerator. That would make 10,000 mph easy. Go Figure Bert
[/quote:5cffa51d9f]
Actually, they would work best in a vacuum.
If the air density is non-zero, then the train *still* has to push the
air in front of it out of the way. Inside a tunnel this would be a
problem, and would effectively limit the train to sub-sonic speeds.
Leave the train out in the open, and the air can easily be pushed out
of the way to the side.
Tom Davidson
Richmond, VA |
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