10 ms·

Elon Musk's Hyperloop is viable, says maker of simulation software

175 points by T-A 13y ago

WalterSear 13y ago
"Not on your life, my hindu friend!"
- InclinedPlane 13y ago
  It's a good joke but HN isn't about jokes, people are trying to having a conversation on a topic and random jokes merely make that more difficult.
- icecreampain 13y ago
  Downvote, eh? It appears as if there are tightasses here that haven't seen the monorail Simpons episode.
  - stbtrax 13y ago
    This is not reddit, and it seems to be a problem with engineers of a certain age, but no one wants to constantly hear your 20 year old cartoon references throughout the day. Also I am incredibly glad that the most prominent south asian on network TV isn't a white dude's impression of a stereotypical immigrant.
gkoberger 13y ago
Slightly misleading. They said "it could work". FTA: "I don’t immediately see any red flags. I think it is quite viable."
- epistasis 13y ago
  What is misleading? Was there a different title at some point?
- gkoberger 13y ago
  EDIT: Title was changed since I posted that. It originally said "it will work".
RoboTeddy 13y ago
On viability: what's the state of the tunnel thermal expansion issue? (Last I heard, it seemed like there might not be easy workarounds)
- kornork 13y ago
  Yeah, this seemed like the biggest killer, besides inertia and politics. My friends and I were wondering aloud if you could put a slight bow in the pipe - so instead of expanding lengthwise, the pipe might raise and lower at certain places. Of course, none of us are engineers in that sense.
  - nether 13y ago
    1. Most of the tubes would need some bowing anyway for curves, since they can't find a perfect straight path from LA to SF 2. Tests show that tubes where L >> D, thermal expansion is linear along the length. If you restrained both ends you'd get the buckling in the interior sections that you describe. That might even be a bigger problem though because it would affect the path geometry and alter the attitude control requirements of the pods. I think the wrinkling in the tube skin would also be more dangerous than just letting it stretch.
- toomuchtodo 13y ago
  I am not an engineer outside of IT, but what if you submerged the hyperloop in the pacific between SF and LA? Would thermal expansion no longer be an issue because you're using the ocean as a thermal sink? And you can provide enough positive air pressure to keep water out of your loop.
  - vec 13y ago
    Yeah, but one of the big bullet points is that the tube should be at negative air pressure in order to reduce air resistance.
    - toomuchtodo 13y ago
misnome 13y ago
I'm not exactly impressed by this analysis. I don't recall anyone questioning whether putting a cylinder in a vacuum tube was possible, mainly that it would be horrendously difficult to design, build, tunnel, and reach the high safety margins required, relatively inefficient compared to the alternatives, and that there was lots and lots of hand waving over the real details. They've simulated a vacuum tube, and found that it works.
- InclinedPlane 13y ago
  If you'd actually described any relevant aspect of Hyperloop your criticism might have more credibility, as it stands it has none. Hyperloop is not a vacuum tube train, and the primary mechanism it relies on is non-trivial.
  - tptacek 13y ago
    In your rush to point out the error he made about vacuum tubes, you missed his point, which is that the criticisms of the Musk plan don't revolve around the concept being infeasible to execute, but rather that the concept isn't cost-effective or, for that matter, nearly as customer-friendly as the proposal suggests. Specific points that you'd want to address if you were purporting to rebut Hyperloop criticisms: * Because Musk's plan can't leverage existing last-mile infrastructure the way HSRs do, it delivers riders from one very inconvenient location to another, adding 1-2 hours of additional transit time to SF-LA. * Because (by Musk's own admission) destructive disruptions of his pod-in-tube runs are catastrophic in a way that they aren't with HSRs, his plan requires TSA-style airport security, adding an additional 15-30 minutes to every trip. * The cost estimates for the Hyperloop captured only its capex costs and not its operating expenses, so that the per-ticket prices derived from its proposed cost bore no relation to its actual cost structure. * That the tunneling and viaduct cost estimates given in the Hyperloop proposal were so low that they constituted a revolutionary breakthrough in urban planning and structural engineering in their own right; in other words, if he can dig a Hyperloop-capable tunnel for the price his plan suggests, or run an elevated tube as cheaply as he suggests, why waste time with Hyperloops? The answer would be that he can't do either of those things. * That the routing he proposes, particularly with regards to mountain passes, are wildly optimistic, and that a realistic routing will result in a longer run and significantly increased costs. * That the forces involved on passengers in the Hyperloop exceed the tolerances allowed for existing HSRs in ways that are likely to make motion sickness a signficant problem. This article appears to address none of them, and your comment appears to be premised on the idea that those criticisms hadn't been made.
ssmoot 13y ago
It appears the simulation was only of the pods. Not the whole system.
willvarfar 13y ago
Well, if there's one thing Elon's teams at Tesla and SpaceX know, its engineering. He has some top talent.
deleted 13y ago
[deleted]
seanherron 13y ago
I was really hoping this was from the developer of SimCity.
rorrr2 13y ago
Sure, when they figure out how to 1) keep hundreds of miles of tunnels in near vacuum 2) keep said tunnels intact in a seismic area 3) get all the land rights 4) all of the above at a reasonable price
- vectorjohn 13y ago
  1-3 are already figured out, they are not hard problems or very different than the existing proposed HSR line. 4 is addressed and the only part that you can't really know until you dive into actual implementation. It is estimated though.
  - rorrr2 13y ago
    Figured out? Where do we have long near-vacuum tunnels in a seismic area?
    - vectorjohn 13y ago
      I take it you mean to imply that by "figured out" I mean we have a working example. Obviously not, or we wouldn't be lacking a hyperloop. By figured out I mean all the requisite problems have been solved. It isn't a mystery how we could build a tube and put vacuum pumps on it. And we've built plenty of complex structures in seismic areas.
- loceng 13y ago
  It's not a vacuum system ... I don't understand where people are getting this idea. Seismic activity will be taken into consideration. Land rights are part of proposed cost. Estimates based on current costs ... and Elon said likely to find more efficiencies to make it cheaper ...
  - lisper 13y ago
    > It's not a vacuum system (S)he didn't say it was. (S)he said "near vacuum." And that comes straight from the hyperloop paper: "Just as aircraft climb to high altitudes to travel through less dense air, Hyperloop encloses the capsules in a reduced pressure tube. The pressure of air in Hyperloop is about 1/6 the pressure of the atmosphere on Mars. This is an operating pressure of 100 Pascals, which reduces the drag force of the air by 1,000 times relative to sea level conditions and would be equivalent to flying above 150,000 feet altitude."
dragonwriter 13y ago
The article makes it sounds like this somehow counters the criticism of the Hyperloop, but all the criticism I saw was of the cost estimates of the infrastructure, the utility of a route with the proposed termini, and the idea that a paper concept with no demonstrated prototype was a serious near-term alternative to high speed rail, while the issues this addresses is the basic viability of the "pod in a tube" mechanism (which it says is basically sound in outline -- but needs to be done in a different way than actually proposed in Musk's paper.) So, it's basically a validation that the part was least criticized is probably basically viable in some form, though perhaps not the actual form proposed by Musk. (And the one part of the pod-in-tube engineering that was seriously criticized -- the proposed mechanism for addressing thermal expansion over long stretches -- is also not addressed by this discussion.)
- crazytony 13y ago
  I wish we had a more detailed delta (including pricing) on the 'as proposed' vs 'as modeled'. What does reshaping the vehicle do to the cost and fitness for purpose?
crazytony 13y ago
The Ansys simulation showed very uneven stress markings alongside the body of the pod. “We see a lot of shear stress areas,” Sovani says. They didn't study it but I wonder what the stress on the curved portions of the tube wall would be? If the vehicle is prone to shear failures, I would imagine the tube would be as well.
gametheoretic 13y ago
Structural superiority of Tacoma Narrows beyond question. Automobile farers can expect to enjoy bridge commute for centuries to come. --top 1940 scale-model builder
- jlgreco 13y ago
  "I think it is quite viable." "beyond question" One of these people is speaking in foolishly strong terms.
dangero 13y ago
I'm still hung up on what happens if there's an emergency on board? Yes, bathroom related would be one, but what about something like a heart attack? Are there any other forms of mass transit that don't allow for an emergency stop or at least the possibility of gaining reasonable assistance from another person on board? I guess the closest comparison would be an intercontinental plane, but planes have space to move around and bathrooms.
- jlgreco 13y ago
  "what about something like a heart attack?" Well, with an average of 15 minutes until you arrive at the other end, where presumably EMTs are already waiting, I don' think you really need a close comparison. 15 minute response times are hardly unheard of and you can put yourself in a much more isolated situation just driving down the road in a car in some of the less dense parts of America. I don't think this is a problem that actually needs a solution (though the public may very well demand one irrationally, much like the safety concerns the public is going to have with self-driving cars that are safer than human drivers...).
  - robbiep 13y ago
    I agree, I don't see the damage. In most real life situations anything that doesn't kill you immediately can wait 15-20 minutes, and when you get out the other end you can have great medical treatment. Anything that requires you to be seen by some serious medical support faster than that will generally kill you regardless of the situation (ie. Left Main coronary embolism which kills 250,000 Americans a year) Edit: complete misuse of iatrogenic. Too little sleep. Whoops
- coldtea 13y ago
  >I'm still hung up on what happens if there's an emergency on board? Yes, bathroom related would be one, but what about something like a heart attack? Are there any other forms of mass transit that don't allow for an emergency stop or at least the possibility of gaining reasonable assistance from another person on board? Well, how it's different from a regular high speed train? (Besides reaching it's destination much much faster?) Where would a regular high speed train do an emegergency stop? Other methods could be even worse, despite far more popular. A taxi in a traffic jam for one. You'd probably need more than 15 minutes to get to a hospital.
chadwickthebold 13y ago
'Ansys...has fed the Hyperloop specifications into a computer..' I love technical explanations like this. I think the specifications could have used more salt.
icambron 13y ago
#1: "We need some publicity. Maybe we can ride Hyperloop's hype coattails." #2: "Yeah, we could simulate it and talk about the results in technical sounding but vague terms that we can't be meaningfully challenged on. But what do think will get more publicity, saying it will work or that it won't? There's plenty of latitude in the specs for us to end up with either." #1: "That it will, of course. We want our customers to think they'll be validated by our software, not shot down. But make sure you provide a little advice so it's clear that we add value. And also hedge a bit so that just in case Hyperloop is a technical disaster, we don't look terrible." #2: "Sounds good. I'll call Bloomberg and see if they have any spots available for vacuous puff pieces." #1: "Was that a vacuum joke?"
- NamTaf 13y ago
  Ansys does not really need publicity. They're essentially the biggest multiphysics FE package out there. That said, Bloomberg news as an outlet to explain technical info is always doomed for failure.
  - chad_oliver 13y ago
    Apple doesn't need publicity. They're essentially the biggest smartphone out there.
    - stirbot 13y ago
      You buy ANSYS because you need it, not because you were compelled by an advertisement to have the latest version.
- neurotech1 13y ago
  I'm under the distinct impression that the decision if the Hyperloop is built is less about technical details and more about project cost. It's not like the engineers working with Elon Musk are taking a break from designing rockets - oh wait - The engineers at spaceX build rockets that go into orbit.
  - 13y ago
triggercut 13y ago
How many large scale infrastructure projects has this software company executed and delivered? Oh, they just supply software to people that do do that? Ok.
robomartin 13y ago
My friends in aerospace always say that there are two kinds of folks who believe simulations: Those who write the software and those who have to use it to justify their existence. Everyone else knows there's can be huge gaps between simulation and reality. Granted, things improve over the years but c'mon, who are they kidding. > “I don’t immediately see any red flags,” Says the simulation guy. Really? > “I think it is quite viable.” Says the simulation guy. Again. Hmmm. I'm not building rockets or cars but, you know what, I'll bet you --simulation guy-- a good dinner this thing is as viable as trying to evolve a flying elephant in a lab. You might theoretically be able to get there with enough time, but in practical terms it is impossible. For starters I want someone to explain how we are going to build massive columns along the middle of Interstate 5 every 100 meters for four hundred miles. And then tell me how we are going to do that and put a four hundred mile tube on top of it (let's ignore impossible construction details) for six billion dollars when building an incredibly short (by comparison) bridge in San Francisco cost the same? Simulations like this one are like special effects in movies. They look great and make you feel like we are living in the future but they are far --very far-- from being realized. Look at something like C3PO. Thirty six years have passed and we are nowhere near such a robot being realized. Me thinks simulation guy wants free publicity.
shishir1 13y ago
Having Symmetry and exact shape is more of an optimization issue. Ansys numerical simulation tools are not really needed for feasibility check. Hand calculations are sufficient, mostly taken care of in the alpha design document. However, the issue of having sufficient space to store steam is somewhat unclear and needs some brainstorming..
Shivetya 13y ago
Technically viable possibly, and about as economically viable as all other rail solutions offered so far in the US. Speed isn't the issue with rail, its point A and point B, well that isn't really fair. The number one obstacle to rail has always been politicians who take any well conceived route and demand it go to their hometown.
loudmax 13y ago
I really hope this project gets off the ground. I don't know if it will prove financially viable in the end. Maybe the most it will accomplish is serve as an experiment to tease out aspects of high speed transportation that would work from those that don't. Progress is made by pushing the envelope of what's feasible. The biggest shame of all would be to become a society that is so afraid of making mistakes that we can't move forward.

175 points by T-A 13y ago

WalterSear 13y ago

"Not on your life, my hindu friend!"

InclinedPlane 13y ago
It's a good joke but HN isn't about jokes, people are trying to having a conversation on a topic and random jokes merely make that more difficult.
icecreampain 13y ago
Downvote, eh? It appears as if there are tightasses here that haven't seen the monorail Simpons episode.
- stbtrax 13y ago
  This is not reddit, and it seems to be a problem with engineers of a certain age, but no one wants to constantly hear your 20 year old cartoon references throughout the day. Also I am incredibly glad that the most prominent south asian on network TV isn't a white dude's impression of a stereotypical immigrant.

gkoberger 13y ago

Slightly misleading. They said "it could work". FTA: "I don’t immediately see any red flags. I think it is quite viable."

epistasis 13y ago
What is misleading? Was there a different title at some point?
gkoberger 13y ago
EDIT: Title was changed since I posted that. It originally said "it will work".

RoboTeddy 13y ago

On viability: what's the state of the tunnel thermal expansion issue? (Last I heard, it seemed like there might not be easy workarounds)

kornork 13y ago
Yeah, this seemed like the biggest killer, besides inertia and politics. My friends and I were wondering aloud if you could put a slight bow in the pipe - so instead of expanding lengthwise, the pipe might raise and lower at certain places. Of course, none of us are engineers in that sense.
- nether 13y ago
  1. Most of the tubes would need some bowing anyway for curves, since they can't find a perfect straight path from LA to SF 2. Tests show that tubes where L >> D, thermal expansion is linear along the length. If you restrained both ends you'd get the buckling in the interior sections that you describe. That might even be a bigger problem though because it would affect the path geometry and alter the attitude control requirements of the pods. I think the wrinkling in the tube skin would also be more dangerous than just letting it stretch.
toomuchtodo 13y ago
I am not an engineer outside of IT, but what if you submerged the hyperloop in the pacific between SF and LA? Would thermal expansion no longer be an issue because you're using the ocean as a thermal sink? And you can provide enough positive air pressure to keep water out of your loop.
- vec 13y ago
  Yeah, but one of the big bullet points is that the tube should be at negative air pressure in order to reduce air resistance.
  - toomuchtodo 13y ago

misnome 13y ago

I'm not exactly impressed by this analysis. I don't recall anyone questioning whether putting a cylinder in a vacuum tube was possible, mainly that it would be horrendously difficult to design, build, tunnel, and reach the high safety margins required, relatively inefficient compared to the alternatives, and that there was lots and lots of hand waving over the real details. They've simulated a vacuum tube, and found that it works.

InclinedPlane 13y ago
If you'd actually described any relevant aspect of Hyperloop your criticism might have more credibility, as it stands it has none. Hyperloop is not a vacuum tube train, and the primary mechanism it relies on is non-trivial.
- tptacek 13y ago
  In your rush to point out the error he made about vacuum tubes, you missed his point, which is that the criticisms of the Musk plan don't revolve around the concept being infeasible to execute, but rather that the concept isn't cost-effective or, for that matter, nearly as customer-friendly as the proposal suggests. Specific points that you'd want to address if you were purporting to rebut Hyperloop criticisms: * Because Musk's plan can't leverage existing last-mile infrastructure the way HSRs do, it delivers riders from one very inconvenient location to another, adding 1-2 hours of additional transit time to SF-LA. * Because (by Musk's own admission) destructive disruptions of his pod-in-tube runs are catastrophic in a way that they aren't with HSRs, his plan requires TSA-style airport security, adding an additional 15-30 minutes to every trip. * The cost estimates for the Hyperloop captured only its capex costs and not its operating expenses, so that the per-ticket prices derived from its proposed cost bore no relation to its actual cost structure. * That the tunneling and viaduct cost estimates given in the Hyperloop proposal were so low that they constituted a revolutionary breakthrough in urban planning and structural engineering in their own right; in other words, if he can dig a Hyperloop-capable tunnel for the price his plan suggests, or run an elevated tube as cheaply as he suggests, why waste time with Hyperloops? The answer would be that he can't do either of those things. * That the routing he proposes, particularly with regards to mountain passes, are wildly optimistic, and that a realistic routing will result in a longer run and significantly increased costs. * That the forces involved on passengers in the Hyperloop exceed the tolerances allowed for existing HSRs in ways that are likely to make motion sickness a signficant problem. This article appears to address none of them, and your comment appears to be premised on the idea that those criticisms hadn't been made.

ssmoot 13y ago

It appears the simulation was only of the pods. Not the whole system.

willvarfar 13y ago

Well, if there's one thing Elon's teams at Tesla and SpaceX know, its engineering. He has some top talent.

deleted 13y ago

[deleted]

seanherron 13y ago

I was really hoping this was from the developer of SimCity.

rorrr2 13y ago

Sure, when they figure out how to 1) keep hundreds of miles of tunnels in near vacuum 2) keep said tunnels intact in a seismic area 3) get all the land rights 4) all of the above at a reasonable price

vectorjohn 13y ago
1-3 are already figured out, they are not hard problems or very different than the existing proposed HSR line. 4 is addressed and the only part that you can't really know until you dive into actual implementation. It is estimated though.
- rorrr2 13y ago
  Figured out? Where do we have long near-vacuum tunnels in a seismic area?
  - vectorjohn 13y ago
    I take it you mean to imply that by "figured out" I mean we have a working example. Obviously not, or we wouldn't be lacking a hyperloop. By figured out I mean all the requisite problems have been solved. It isn't a mystery how we could build a tube and put vacuum pumps on it. And we've built plenty of complex structures in seismic areas.
loceng 13y ago
It's not a vacuum system ... I don't understand where people are getting this idea. Seismic activity will be taken into consideration. Land rights are part of proposed cost. Estimates based on current costs ... and Elon said likely to find more efficiencies to make it cheaper ...
- lisper 13y ago
  > It's not a vacuum system (S)he didn't say it was. (S)he said "near vacuum." And that comes straight from the hyperloop paper: "Just as aircraft climb to high altitudes to travel through less dense air, Hyperloop encloses the capsules in a reduced pressure tube. The pressure of air in Hyperloop is about 1/6 the pressure of the atmosphere on Mars. This is an operating pressure of 100 Pascals, which reduces the drag force of the air by 1,000 times relative to sea level conditions and would be equivalent to flying above 150,000 feet altitude."

dragonwriter 13y ago

The article makes it sounds like this somehow counters the criticism of the Hyperloop, but all the criticism I saw was of the cost estimates of the infrastructure, the utility of a route with the proposed termini, and the idea that a paper concept with no demonstrated prototype was a serious near-term alternative to high speed rail, while the issues this addresses is the basic viability of the "pod in a tube" mechanism (which it says is basically sound in outline -- but needs to be done in a different way than actually proposed in Musk's paper.) So, it's basically a validation that the part was least criticized is probably basically viable in some form, though perhaps not the actual form proposed by Musk. (And the one part of the pod-in-tube engineering that was seriously criticized -- the proposed mechanism for addressing thermal expansion over long stretches -- is also not addressed by this discussion.)

crazytony 13y ago
I wish we had a more detailed delta (including pricing) on the 'as proposed' vs 'as modeled'. What does reshaping the vehicle do to the cost and fitness for purpose?

crazytony 13y ago

The Ansys simulation showed very uneven stress markings alongside the body of the pod. “We see a lot of shear stress areas,” Sovani says. They didn't study it but I wonder what the stress on the curved portions of the tube wall would be? If the vehicle is prone to shear failures, I would imagine the tube would be as well.

gametheoretic 13y ago

Structural superiority of Tacoma Narrows beyond question. Automobile farers can expect to enjoy bridge commute for centuries to come. --top 1940 scale-model builder

jlgreco 13y ago
"I think it is quite viable." "beyond question" One of these people is speaking in foolishly strong terms.

dangero 13y ago

I'm still hung up on what happens if there's an emergency on board? Yes, bathroom related would be one, but what about something like a heart attack? Are there any other forms of mass transit that don't allow for an emergency stop or at least the possibility of gaining reasonable assistance from another person on board? I guess the closest comparison would be an intercontinental plane, but planes have space to move around and bathrooms.

jlgreco 13y ago
"what about something like a heart attack?" Well, with an average of 15 minutes until you arrive at the other end, where presumably EMTs are already waiting, I don' think you really need a close comparison. 15 minute response times are hardly unheard of and you can put yourself in a much more isolated situation just driving down the road in a car in some of the less dense parts of America. I don't think this is a problem that actually needs a solution (though the public may very well demand one irrationally, much like the safety concerns the public is going to have with self-driving cars that are safer than human drivers...).
- robbiep 13y ago
  I agree, I don't see the damage. In most real life situations anything that doesn't kill you immediately can wait 15-20 minutes, and when you get out the other end you can have great medical treatment. Anything that requires you to be seen by some serious medical support faster than that will generally kill you regardless of the situation (ie. Left Main coronary embolism which kills 250,000 Americans a year) Edit: complete misuse of iatrogenic. Too little sleep. Whoops
coldtea 13y ago
>I'm still hung up on what happens if there's an emergency on board? Yes, bathroom related would be one, but what about something like a heart attack? Are there any other forms of mass transit that don't allow for an emergency stop or at least the possibility of gaining reasonable assistance from another person on board? Well, how it's different from a regular high speed train? (Besides reaching it's destination much much faster?) Where would a regular high speed train do an emegergency stop? Other methods could be even worse, despite far more popular. A taxi in a traffic jam for one. You'd probably need more than 15 minutes to get to a hospital.

chadwickthebold 13y ago

'Ansys...has fed the Hyperloop specifications into a computer..' I love technical explanations like this. I think the specifications could have used more salt.

icambron 13y ago

#1: "We need some publicity. Maybe we can ride Hyperloop's hype coattails." #2: "Yeah, we could simulate it and talk about the results in technical sounding but vague terms that we can't be meaningfully challenged on. But what do think will get more publicity, saying it will work or that it won't? There's plenty of latitude in the specs for us to end up with either." #1: "That it will, of course. We want our customers to think they'll be validated by our software, not shot down. But make sure you provide a little advice so it's clear that we add value. And also hedge a bit so that just in case Hyperloop is a technical disaster, we don't look terrible." #2: "Sounds good. I'll call Bloomberg and see if they have any spots available for vacuous puff pieces." #1: "Was that a vacuum joke?"

NamTaf 13y ago
Ansys does not really need publicity. They're essentially the biggest multiphysics FE package out there. That said, Bloomberg news as an outlet to explain technical info is always doomed for failure.
- chad_oliver 13y ago
  Apple doesn't need publicity. They're essentially the biggest smartphone out there.
  - stirbot 13y ago
    You buy ANSYS because you need it, not because you were compelled by an advertisement to have the latest version.
neurotech1 13y ago
I'm under the distinct impression that the decision if the Hyperloop is built is less about technical details and more about project cost. It's not like the engineers working with Elon Musk are taking a break from designing rockets - oh wait - The engineers at spaceX build rockets that go into orbit.
- 13y ago

triggercut 13y ago

How many large scale infrastructure projects has this software company executed and delivered? Oh, they just supply software to people that do do that? Ok.

robomartin 13y ago

My friends in aerospace always say that there are two kinds of folks who believe simulations: Those who write the software and those who have to use it to justify their existence. Everyone else knows there's can be huge gaps between simulation and reality. Granted, things improve over the years but c'mon, who are they kidding. > “I don’t immediately see any red flags,” Says the simulation guy. Really? > “I think it is quite viable.” Says the simulation guy. Again. Hmmm. I'm not building rockets or cars but, you know what, I'll bet you --simulation guy-- a good dinner this thing is as viable as trying to evolve a flying elephant in a lab. You might theoretically be able to get there with enough time, but in practical terms it is impossible. For starters I want someone to explain how we are going to build massive columns along the middle of Interstate 5 every 100 meters for four hundred miles. And then tell me how we are going to do that and put a four hundred mile tube on top of it (let's ignore impossible construction details) for six billion dollars when building an incredibly short (by comparison) bridge in San Francisco cost the same? Simulations like this one are like special effects in movies. They look great and make you feel like we are living in the future but they are far --very far-- from being realized. Look at something like C3PO. Thirty six years have passed and we are nowhere near such a robot being realized. Me thinks simulation guy wants free publicity.

shishir1 13y ago

Having Symmetry and exact shape is more of an optimization issue. Ansys numerical simulation tools are not really needed for feasibility check. Hand calculations are sufficient, mostly taken care of in the alpha design document. However, the issue of having sufficient space to store steam is somewhat unclear and needs some brainstorming..

Shivetya 13y ago

Technically viable possibly, and about as economically viable as all other rail solutions offered so far in the US. Speed isn't the issue with rail, its point A and point B, well that isn't really fair. The number one obstacle to rail has always been politicians who take any well conceived route and demand it go to their hometown.

loudmax 13y ago

I really hope this project gets off the ground. I don't know if it will prove financially viable in the end. Maybe the most it will accomplish is serve as an experiment to tease out aspects of high speed transportation that would work from those that don't. Progress is made by pushing the envelope of what's feasible. The biggest shame of all would be to become a society that is so afraid of making mistakes that we can't move forward.