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Switzerland to test ‘hyperloop’ train technologies

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Re: Switzerland to test ‘hyperloop’ train technologies

#31

Post by ucaetano »

jpatokal wrote: post #23
ucaetano wrote: post #20

Earlier quoted context omitted.

Indeed, but the network benefits dramatically from - naturally - network effects. Today you rarely ever see infrastructure projects in Switzerland which are incompatible with the existing network. If you build a hyperloop tunnel, only hyperloop cars will be able to use it, and only in the tunnel. If you build a rail tunnel, it is automatically integrated into the huge existing rail infrastructure. Unless, of course,…

It's worth noting that both France and Japan have a number of high-speed trains that run onto regular track -- although in Japan's case the different rail gauge made this difficult enough that neither approach (dual rails or flex trains) has been widely adopted. https://en.wikipedia.org/wiki/Mini-shinkansen https://en.wikipedia.org/wiki/Gauge_Change_Train

Sure, the TGV is a standard-gauge set that can run in most of Western Europe's rail.

The issue is that regular rail can't run on the TGV lines.

Japan/France took a different approach than Germany/Switzerland for HSR. Germany and Switzerland are far less centralized than Japan and France, and that reflects in the network, which began as upgrades to lines between major cities, and new sections with new tracks.

France's system reflects its historical centralization, since the late middle ages. Paris is the economic, political, artistic, demographic center of the country, and just like the first railroads in the country were created to expand central control over the rest of the country, TGV started as a spoke network with a single hub: Paris.

Re: Switzerland to test ‘hyperloop’ train technologies

#32

Post by chki »

microtherion wrote: post #24
ip26 wrote: post #21

Earlier quoted context omitted.

I think it's the opposite really, you black out at much lower g forces when accelerating head first compared to face front. Not proof of anything but notice rocket crew always face front.

Interesting! But presumably in this setup, one would experience both significant acceleration AND deceleration. Is there any static orientation that would minimize problems for both?

Well, sideways or rather upright (possibly in a seating position) is probably better but seems not very aerodynamic. I think those are the three possible orientations. But I mean are we seriously considering a transportation system where part of the journey is a black out/red out? The time gain by accelerating with 5g instead of 1g can't be that big (Maybe a few minutes at most?).

Edit: I'm not sure if there's an error in my calculations but with 1g acceleration it should take about 25s to get to 900km/h? That seems ok.

Re: Switzerland to test ‘hyperloop’ train technologies

#33

Post by StreakyCobra »

icefo wrote: post #19

Damn it feels super weird to hear something about my childhood village on HN. There is also a recently closed refinery there. The funny thing is that they never budgeted the decommissioning cost when it was built. So there is no money to do it and it's probably going to stay like that forever. I hope the don't do the same for this project.

You know what is even more weird? Reading a comment on HN of another person saying he also grew up there ;-)

Re: Switzerland to test ‘hyperloop’ train technologies

#34

Post by microtherion »

chki wrote: post #32
microtherion wrote: post #24

Earlier quoted context omitted.

Interesting! But presumably in this setup, one would experience both significant acceleration AND deceleration. Is there any static orientation that would minimize problems for both?

Well, sideways or rather upright (possibly in a seating position) is probably better but seems not very aerodynamic. I think those are the three possible orientations. But I mean are we seriously considering a transportation system where part of the journey is a black out/red out? The time gain by accelerating with 5g instead of 1g can't be that big (Maybe a few minutes at most?). Edit: I'm not sure if there's an err…

I agree with your calculations, but with an 1g acceleration for 25s, the train will travel a bit more than 3km, and getting to the end of the track (which is 3km according to the article) at close to 900km/h is unlikely to lead to a happy outcome.

If my math is right, in order to accelerate to 900km/h and decelerate to a stop again, all on a 3km track, requires acceleration/deceleration of a bit more than 2g.

Re: Switzerland to test ‘hyperloop’ train technologies

#35

Post by salimmadjd »

Hyperloop only works most comfortably in very flat routes. It's something I never realized until I visited Hyperloop's offices in LA when they first started.

I got to make some early promo photos for them [0] and signed a 10-year NDA in the process. However, what I learned (which is public knowledge) that at high speeds even smallest elevation drops would make the passengers feel the free-fall sensation of being on a rollercoaster. Basically at high speeds the elevation change of the vertical vector components of anything more than several degrees can approach the free fall dropping speeds.

I have also taken numerous train rides in Switzerland and driven through large parts of the country and I don't believe the technology can be used there as well as it could have been deployed in other routes in the world that is naturally more flat. So I'm wondering if this mostly an R&D project designed to export an entire tunnel/hyperloop making solution.

[0] https://www.instagram.com/p/BMiyAIdhCJn/ (photo is about 80 frames stacked. Because we only had one welder at the time and I had to reuse him and also to intricately light every parts of this lot)

Re: Switzerland to test ‘hyperloop’ train technologies

#36

Post by tdeck »

salimmadjd wrote: post #35

Hyperloop only works most comfortably in very flat routes. It's something I never realized until I visited Hyperloop's offices in LA when they first started. I got to make some early promo photos for them [0] and signed a 10-year NDA in the process. However, what I learned (which is public knowledge) that at high speeds even smallest elevation drops would make the passengers feel the free-fall sensation of being on a…

I wonder if people would just get used to that sensation if it meant cutting their commute in half.

Re: Switzerland to test ‘hyperloop’ train technologies

#37

Post by jcranmer »

salimmadjd wrote: post #35

Hyperloop only works most comfortably in very flat routes. It's something I never realized until I visited Hyperloop's offices in LA when they first started. I got to make some early promo photos for them [0] and signed a 10-year NDA in the process. However, what I learned (which is public knowledge) that at high speeds even smallest elevation drops would make the passengers feel the free-fall sensation of being on a…

The thing about ultra-high-speed is this: your benefits (travel time) grow linearly with speed, but your problems (energy, capacity, curve radii, etc.) grow quadratically.

Actually, it's worse than it sounds. Travel time has a big impact on demand--but only within a small-ish window, about 2-4 hours. Outside of that window, demand does not respond that much to changes in travel time. That means that higher speeds are ultimately about trying to bring more destinations within the acceptable travel time window, but you also have to give up destinations within that window because the stop time penalties are too high.

Switzerland has the issue that it's just too small. With conventional 300-350km/h max-speed HSR, going from the eastern to the western edge of the country could be done in about 2 hours (recall that average speed is going to be less than max speed, particularly when stops are included), which is around the point where going faster means getting no practical benefit for people. It could serve international routes, but then Switzerland is bearing the costs without reaping the benefits, which the citizenry tends not to favor very highly.

Re: Switzerland to test ‘hyperloop’ train technologies

#38

Post by seanmcdirmid »

jcranmer wrote: post #37
salimmadjd wrote: post #35

Hyperloop only works most comfortably in very flat routes. It's something I never realized until I visited Hyperloop's offices in LA when they first started. I got to make some early promo photos for them [0] and signed a 10-year NDA in the process. However, what I learned (which is public knowledge) that at high speeds even smallest elevation drops would make the passengers feel the free-fall sensation of being on a…

The thing about ultra-high-speed is this: your benefits (travel time) grow linearly with speed, but your problems (energy, capacity, curve radii, etc.) grow quadratically. Actually, it's worse than it sounds. Travel time has a big impact on demand--but only within a small-ish window, about 2-4 hours. Outside of that window, demand does not respond that much to changes in travel time. That means that higher speeds are…

Even the HSR that operates in Switzerland, the TGV, doesn't get up to speed until it is well within France. Switzerland tracks aren't straight enough for HSR, and it would cost a lot to straighten them out.

There also isn't a lot of demand for Geneva to Zurich in an hour.

Re: Switzerland to test ‘hyperloop’ train technologies

#39

Post by mcguire »

tdeck wrote: post #36
salimmadjd wrote: post #35

Hyperloop only works most comfortably in very flat routes. It's something I never realized until I visited Hyperloop's offices in LA when they first started. I got to make some early promo photos for them [0] and signed a 10-year NDA in the process. However, what I learned (which is public knowledge) that at high speeds even smallest elevation drops would make the passengers feel the free-fall sensation of being on a…

I wonder if people would just get used to that sensation if it meant cutting their commute in half.

Or they wouldn't get those jobs.
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