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Hyperloop - yes or no?


Is hyperloop a hyper proposal or just hype  

103 members have voted

  1. 1. Do you think hyperloop is a viable transport technology which will be adopted?

    • Yes, it needs work but ultimately it will supplant high speed rail and some air routes
    • No, it's just a hyped up pipe dream
    • The technology has potential but it is unlikely to find more than a niche and is a long way from being viable in the real world


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I imagine points are possible but would probably be suitable for only very low speeds, rather like on monorails where a whole chunk of the track is moved sideways. 

They should be a prerequisite for it being taken seriously as a transportation mode....

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To my mind the pod would leave the station and enter an airlock,  wait a minute or so for the air to be sucked out then move into the tunnel.  At the far end it would stop in the other airlock for a few seconds while air is added before entering the station.  Pods wouldn't need to be in individual vacuums with airlocks,  they could just follow each other down the tube at suitable intervals.

 

The stations being at atmospheric pressure could have points and sidings.  Perhaps rather than having junctions in the tubes one or more central cities could form hubs that all pods stopped at before continuing down a different tube.  It would add to the journey times but give far more flexibility.  I imagine that almost all routes would require 2 tubes for out and back travel,  though perhaps smaller destinations that were a relatively short distance from a hub could cope with a single bidirectional tube.  For example you could theoretically run an hourly service over 300 miles down a single tube if everything ran smoothly and the acceleration up to 700mph was quick enough.

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I'm scratching my head trying to remember the guy's name

but didn't some guy try using a vacuum to move trains around once before ☺

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 Pods wouldn't need to be in individual vacuums with airlocks,  they could just follow each other down the tube at suitable intervals.

So, with a 2610 mile long tube in vacuum and no intermediate airlocks, what happens when you need to send a guy in to fix the track...

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In a tunnel context, does one need a vacuum? A hovercraft would be more energy efficient in a tunnel than it is in the open. One could run a trial with a tunnel under The Solent.

Edited by Joseph_Pestell
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Due to the low air pressure (it's not a total vacuum) there is low aerodynamic drag, therefore the process is highly energy efficient, more energy efficient than traditional modes of transport per passenger mile. Least that's what they told us at the lunchtime meeting. For my two penneth I think it will replace long distance routes, but not in this country in my lifetime. Do I think heavy rail is dead, no, I've worked on four different proposals to reopen lines (and one brand new one) for passenger use in interurban areas in this country but the pace is glacial compared to the work we've done in the middle east (for lots of reasons and not necessarily bad ones).

I don't think it will be cheap to travel on (business class) but I do think it will be cheaper to build than HS2/mile above ground. Everything will be pre-fabricated off site so all you've got to construct on site is the pier type footing, quick erection with low labour costs. Operationally much cheaper, less energy, less moving parts, little interaction with leaves, snow etc. In the cities start a TBM at one end and off you go, same as HS2. I'm guessing the first publicly operational one to will between Abu Dhabi and Dubai: when - it could be years rather than decades if the test one goes well this year, and the technology isn't revolutionary it's just new combined application of currently existing elements.

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So, with a 2610 mile long tube in vacuum and no intermediate airlocks, what happens when you need to send a guy in to fix the track...

 

How do you effect a rescue if a capsule stops or depressurises in a remote part of the tube? 

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How do you effect a rescue if a capsule stops or depressurises in a remote part of the tube? 

In the latter scenario don't bother hurrying, if your breathable air becomes vacuum, then 'rescue' is a bit pointless...

 

In reality, I presume you'd have to have a way of very quickly restoring air pressure in a given section of tube, but to do that again you need airlocks....

 

I don't think it will be cheap to travel on (business class) but I do think it will be cheaper to build than HS2/mile above ground. Everything will be pre-fabricated off site so all you've got to construct on site is the pier type footing, quick erection with low labour costs.

 

I'm really, really sceptical of this too.

 

What exactly makes an elevated/tunnelled vacuum tube cheaper to construct than an equivalently constructed elevated/tunnelled HSR right of way. Are we seriously suggesting that two ribbons of steel and a copper wire are the major part of the construction cost, as that's the only bit that Hyperloop won't need?

 

If not - surely the same construction methods you'd use to build a Hyperloop for "half the cost" can be used to create HSR for less than half the cost.

 

 

 

 

 

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Could be a project for Mr Dyson.

That sounds an interesting combination,

Dyson and Branson, the mind boggles at

what they might come up with together.

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That sounds an interesting combination,

Dyson and Branson, the mind boggles at

what they might come up with together.

Virgin vacuum! ;)

 

Hat, coat etc

Edited by Colin_McLeod
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It appears a lot of people have only heard half the story, the vacuum bit. What gives the pods speed, and considerable savings on energy, is the presence of air behind the pod(s). In effect, the pod is a movable air lock by design. Whether the air behind is atmospheric or higher pressure I'm not sure about, but for safety reasons normal pressure would be my choice.

that was the situation in the old Crystal palace line but is not what is described in the Hyperloop websites, the partial vacuum reduses air resistance, propulsion is mostly shown by maglev.

Although some designs do show propulsion as for a hovercraft they don't explain where the air comes from, the relative vacuum would have to be a lot less.

 

There is an article on Hyperloop in the May issue of the "RailEngineer" magazine, https://issuu.com/railmedia/docs/tre-may-2018/58

Regards

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So, with a 2610 mile long tube in vacuum and no intermediate airlocks, what happens when you need to send a guy in to fix the track...

I wasn't intending that there were no airlocks,  just that you wouldn't be needing to open and close them all the time if several pods were travelling down the same vacuum tube.  It turned out that I was wrong for different reasons (see below).  I would imagine that any chaps fixing things in the tunnel would be done with the whole tunnel shut down in the same way that TFL don't send P-Way staff down the tube tunnels when trains are running.

 

 

What exactly makes an elevated/tunnelled vacuum tube cheaper to construct than an equivalently constructed elevated/tunnelled HSR right of way. Are we seriously suggesting that two ribbons of steel and a copper wire are the major part of the construction cost, as that's the only bit that Hyperloop won't need?

 

If not - surely the same construction methods you'd use to build a Hyperloop for "half the cost" can be used to create HSR for less than half the cost.

 

 

 

Because you don't have to pay for the land and move roads,streams,other railways and 17 great creasted newts.  Very little of it is visible so apart from carefully steering around any very deep cellars you only need to worry about geology.

 

 

It appears a lot of people have only heard half the story, the vacuum bit. What gives the pods speed, and considerable savings on energy, is the presence of air behind the pod(s). In effect, the pod is a movable air lock by design. Whether the air behind is atmospheric or higher pressure I'm not sure about, but for safety reasons normal pressure would be my choice.

 

Thanks for that,  your 2 sentences explain more about this than our 3 pages of wittering.  Could you let on where you found out?

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That sounds an interesting combination,

Dyson and Branson, the mind boggles at

what they might come up with together.

 

James sucks at one end,, Richard blows at the other - result pod moves !!!!!!!

 

Brit15

Edited by APOLLO
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Common sense :P  Oh, and an understanding of physics is also helpful ;)  Besides, I've read an article about it on a Dutch news site some time ago (about when the original tests were held, the Dutch contenders actually won), but d@rned if I could find it again ATM :no:

Pretty sure the air propulsion thing is a myth.  If nothing else, the effectiveness of air propulsion drops significantly as the vehicle speed gets closer to the speed of sound.  And how many, and how big, airlocks would be needed to have a succession of vehicles each with vacuum in front and air behind?  What would that mean for the spacing between vehicle - probably many miles? 

 

Effectively this seems to be a maglev, similar concept to that used in Shanghai and under development in Japan, but put in a vacuum tube to eliminate aerodynamic resistance. 

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I wasn't intending that there were no airlocks,  just that you wouldn't be needing to open and close them all the time if several pods were travelling down the same vacuum tube.  It turned out that I was wrong for different reasons (see below).  I would imagine that any chaps fixing things in the tunnel would be done with the whole tunnel shut down in the same way that TFL don't send P-Way staff down the tube tunnels when trains are running.

 

So the answer is to shut down 2610 miles of network (or 5220 miles if it's a continuous loop!) to fix it?

 

 

 

Because you don't have to pay for the land and move roads,streams,other railways and 17 great creasted newts.  Very little of it is visible so apart from carefully steering around any very deep cellars you only need to worry about geology.

 

Please read the question again....

 

What exactly makes an elevated/tunnelled vacuum tube cheaper to construct than an equivalently constructed elevated/tunnelled HSR right of way.

 

Put slightly differently:

 

Why is an elevated vacuum tube supposedly much cheaper than an elevated railway?

Why is a tunnelled vacuum tube supposedly cheaper than a tunnelled railway?

 

If putting the right-of-way into tunnel made it cheaper, surely we'd never build above-ground railways.

In real life, tunnelling is more, much, much more expensive than surface construction, irrespective of how many newts are involved.

 

* Land take for rail should be no worse, possibly even better (higher speeds logically mean larger curves.)

* Whilst the train "floats", there's no such thing as zero gravity - (it still pushes down on the track with it's weight, it will still push sideways on curves) - so any structures still have to cope with and be strong enough to deal with train forces.

* You do save two rails, and a copper wire, and the kit to support those.

* But conversely you'd need to build your structure strongly and precisely enough to maintain a vacuum, which I suspect no current rail bridge or tunnel has to.

* And you need to install a maglev "rail", and all the gear to power that.

* And you need some kind of air management systems too, which aren't likely to be lightweight. 

 

Again - what magically makes it "cheaper" - if there's a way of building a tunnelled or elevated right of way for half the cost, we need to be building railways on it!

 

 

 

 

 

Edited by Glorious NSE
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Reduced live and dynamic loads result in lighter structures resulting in cost savings. There are little to no cost savings in the tunnelling of the tubes but the station costs are considerably smaller as the cavern for the station is considerably smaller. Some sample figures in the public domain: Standard rail budget cost $10m/mile, High Speed $100m/mile, Hyperloop $70m/mile.

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The Indians are planning one from Delhi to Calcutta.

 

RaPjB39P_460s.jpg

 

Brit15

I see they're still planning to have people

riding on top of the train as well as inside!

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