5 ms·
As long as we're guessing, here's my idea. An electrically propelled train in a tube. Instead of evacuating the tunnel you have ducts in the walls that vent the
by cookingrobot 13y ago
As long as we're guessing, here's my idea. An electrically propelled train in a tube. Instead of evacuating the tunnel you have ducts in the walls that vent the high-pressure air from in front of the train to the low-pressure sides/bottom/rear of the train.
This should reduce the energy wasted trying to push a shockwave through the tunnel, and would use the air pressure to keep the train off the walls. This would fit with his "air-hockey" comment, and wouldn't be an evacuated tunnel - which he said it isn't.
edit: And the "loop" part of the name is because the air ducts are loops the same length as the train. They move the air directly from in front where it's high pressure to the rear where it's low pressure.
- nitrogen 13y agoMy guess: Musk is throwing random keywords at the Internet, then feeding all the speculative ideas generated by smart geeks to his engineering team until they come up with the real product ;-).
- nickik 13y agoThe Hivemind is read.
- nitrogen 13y agoAfter I posted this, I noticed a top level comment with the same idea from an account that's been dead for nearly two years, apparently for posting an Office Space joke: stiller 3 hours ago | link [dead] At this rate, Elon can simply wait until somebody comes up with a viable plan and say, "yes, that's what Hyperloop was all along." https://news.ycombinator.com/user?id=stiller https://news.ycombinator.com/user?id=stiller
- saraid216 13y agoRobert Jordan actually joked he did this with his novels. He'd just read fansites to see what was the most plausible explanation for an event and go with it.
- mbenjaminsmith 13y agoI would go one step further and say that the mechanism you describe would also keep the train off the floor (and would possibly be handled by the train, not the tunnel). It seems to me that using electromagnets for propulsion only and not for levitation would drastically reduce costs. I could only guess at the aerodynamics but I have a feeling you could just give the train a flat bottom and make the end of the train pointed like the intake of a jet engine. At speed it would compress the air and force it between the train and the floor of the tube in a way similar to how an air bearing functions. (Actually all sides, assuming it was rectangular, would work in the same way.)
- btilly 13y agoI had the same guess. See http://bentilly.blogspot.com/2012/11/speculating-about-hyperloop.html http://bentilly.blogspot.com/2012/11/speculating-about-hyper... for proof. In thinking afterwards about the many good comments that dpark made in the resulting HN discussion, I convinced myself that while my idea was neat, it was unlikely to be correct. (I did not say so anywhere in the discussion because by the time I had worked this out for myself, the discussion was long over.)
- Vivtek 13y agoYeah, there are real problems with an evacuated tunnel - such as the fact that any air leak in its hundreds of miles makes it a non-evacuated tunnel. Do something like this and you've got the best of both worlds. Elon Musk is making America something I'm proud of again. Or at least trying.
- aidenn0 13y agoI seem to recall Musk specifically said it's not an evacuated tunnel. However, air leaks aren't a huge problem. You just need them to be slower than the pumps that run to maintain low-pressure; since the flow into the tunnel from leaks will increase as the pressure drops in the tunnel, you will reach an equilibrium at some point. For a really leaky tunnel that might be near 1atm; for a well-sealed tunnel it will be near 0atm; a practical transportation tunnel will balance construction and maintenance costs against the diminishing returns of lower pressures.
- joezydeco 13y agoI personally believe Musk is smart enough to avoid thinking about digging tunnels in earthquake zones.