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Hyperloop One Reveals Test Track Progress (computerworld.com.au)
Hyperloop One has released the first photographs of its "proof of concept" test track near Las Vegas, Nevada, and there's now also a couple short videos online.
Slashdot reader angry tapir quotes Computerworld:
The company revealed its progress on Tuesday at the Middle East Rail conference in Dubai, sharing pictures and footage of its Nevada development site dubbed "DevLoop." Taking Elon Musk's Hyperloop concept of a levitating pod in a low-pressure tube, Hyperloop One has developed what is so far the only full-scale, full-system Hyperloop test site...and says it plans to test the entire apparatus this year.
In addition, Investopedia reports that Hyperloop One has now also signed letter of intent agreements to investigate the feasibility of building more hyperloop systems in Finland and the Netherlands.
In addition, Investopedia reports that Hyperloop One has now also signed letter of intent agreements to investigate the feasibility of building more hyperloop systems in Finland and the Netherlands.
Thunderf00t does debunk video of hyperloop
Looking at photos of the test track, you have to wonder how the hell do you get out if something goes wrong?
You cut the bodies out with the Jaws of Life and vacuum up the remains with a ShopVac.
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What happens if there is a sudden "repressurization"?
You cut the bodies out with the Jaws of Life and vacuum up the remains with a ShopVac.
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What if the motive element fails and the pod comes to a halt? There you are, stuck in a sealed tube.
You cut the bodies out with the Jaws of Life and cart them away on gurneys.
Just cruising through this digital world at 33 1/3 rpm...
How do you get out of an airplane when something goes wrong ?
Sure, try jumping out with a parachute at 30K feet from a jetliner running 550 knots. I did see one design for a commercial passenger jet with ejectable modules for all passengers. A ticket in something like that from NY to LA would run about 50 thousand dollars. Considering air travel is safer than any form of land travel on a passenger mile basis I guess they decided to forgo the expense.
I never cease to be amazed how many people think vacuum exerts a massive amount of pressure; Hollywood has a *LOT* to answer for for all those ridiculous explosive decompression scenes. The pressure between hard vacuum and atmosphere at sea level is exactly 1 atmosphere; you can get more pressure differential in a typical swimming pool. There's a reason spacecraft are about as rigid as a tin can and submarines are built out of many tonnes of steel and titanium, and it's that one has to deal with some pressure and the other... doesn't. If anything, the tube of the hyperloop is likely to be under more stress from the capilliary action of the vehicles (are we going with rail terminology and calling them "cars" or something else?) and bowshock in the less than perfect vacuum then pressure from the external atmosphere.
UNIX? They're not even circumcised! Savages!
I never cease to be amazed how many people think vacuum exerts a massive amount of pressure; Hollywood has a *LOT* to answer for for all those ridiculous explosive decompression scenes.
In space the pressure is an outward force, in atmosphere it's an inward force.
Vacuum can create the exertion a LOT of pressure. Try the old experiment where you lay a ruler hanging halfway off of a table and cover the end on the table with a sheet of newspaper. Now bang on the end of the ruler that's off the table and see what happens. The ruler stays right where it is because the pressure of the air against the newspaper is actually very significant. Figure 15lbs per sq inch on a 20"x20" sheet of paper (400 sq inches) is 6000 lbs.
People who haven't seen this demonstration are always shocked when the ruler doesn't fly up and take the newspaper with it. You're much more likely to break the ruler off at the edge of the table. Try it if you don't believe me.
Or if you're lazy, watch a demonstration here: https://www.youtube.com/watch?...
I worked with high vacuum quite a bit in my younger days and the forces involved can be immense. The forces involved with the hyperloop are really quite insane and the possibility of an accident is very, very high. The results could be catastrophic to say the least.
Just cruising through this digital world at 33 1/3 rpm...
In space the pressure is an outward force, in atmosphere it's an inward force.
For steel, the compressive and tensile strengths are similar, so it doesn't really matter.
You are probably not far off
https://www.youtube.com/watch?...
We're still reporting on this scam as if it was a real thing? Wow...
Monorail... monorail... MONORAILLLLL
Thunderf00t correctly points out that a small weakness in the structure will cause a full atmosphere of pressure to attempt to breach the vacuum and the initial tearing will become massive in a tiny fraction of a second. The energy required to create a vacuum is quite large, and all of that energy will be inverted in a split second. If you don't believe Thunderf00t's science, try Mythbusters who did something similar with a rail car tanker.
There is an amazing amount of science denial in this thread, and worse.. up moderation of flat out science denial.
-The wise argue that there are few absolutes, the fool argues that there are no probabilities.
-1, physically incorrect description of phenomenon
What is being demonstrated in that video is drag, not air pressure. If you pushed the ruler down slowly the ruler does not break since drag force is a function of velocity squared.
Note that the air pressure on the bottom of the sheet of paper is the same as on the top.
The energy from pressurization is pressure * volume. At a 2.23m diameter (3.906 m^2 cross-sectional area), every km of tube pumped to 95% vacuum represents 376 MJ of energy. With an estimated 500 miles of tube, this represents 188 GJ, or about as much energy as 45 tons of TNT. Granted it's spread out over 500 km so is equivalent to about 82 grams of TNT per meter. That's not an insubstantial amount of energy. But I think a steel tube could be designed to withstand it.
The problem is what happens when a train car traveling 700 mph hits a section of tube damaged by a localized implosion. If a section of tube were somehow weakened, it would fail when the stresses it experienced were highest. This would probably be right when the first car of a train passed it. The weakened section fails inward, and the following train cars hit it at 700 mph.
Yes we fly 500+ mph in planes every day. But those planes don't fly a few cm from things that can suddenly pop out and strike the plane.
There are literally thousands of things which are now practical to build, but weren't at one time. Like the computer I am typing this comment on. Even as little as 10 years ago, there was no practical way to build it to the same specs, even as a one-off prototype.
Your complete lack of logic paints as you a fucked-up moron who deserves to experience extreme decompression -- first hand.
If you want to learn about shock tubes (what is being described), start reading.
You have not replied to a single other post I've written.
It does. Why would you think otherwise?
First off, read the damn document before debating it online. The fact that you don't know that Hyperloop is distinctly not a hard vacuum, and that more to the point would not work in "near perfect vacuum" - one of the most basic aspects of the design - points out that you have no business whatsoever pontificating about the topic.
Secondly, evacuating 2.2m cubic meters at sea level takes a minimum of 223 GJ. Operating on the pessimistic assumption that the tube has to be pressure normalized once annually and zero energy is recovered in the process, divided by six million passenger-trips per year, is 37kJ, or 10,3Wh (note: *not* kWh, just Wh), or about 0.05 cents at industrial rates.
Now, of course, you don't get the thermodynamic minimum. But you were explicitly talking about conservation of energy, so that's the number you were looking for. And if you want to be fair and factor in other energy losses, you also have to factor in that the assumption that you have to empty the tube annually (with zero energy recovery) is unfair on the pessimistic side.
And if you want to know what real-world maintenance level pumping to maintain vacuums is like, LHC requires 170kW for 9000m, or about 19W/m - which in the case of Hyperloop equates to 41,8MW. If this were applied to Hyperloop, that would be a per-passenger cost of 220MJ, or 61kWh, or $30 at industrial power rates. Except that LHC is a hard vacuum, which is orders of magnitude harder to maintain than a mild vacuum like Hyperloop; one of the primary design principles of Hyperloop was avoiding hard vacuum specifically for that reason. Hyperloop's vacuum level is four orders of magnitude higher density than the LHC's cryomagnet insulation volume (we won't even bother discussing the incredibly low beamline vacuum). A simple linear interpolation would suggest a Hyperloop maintenance power of 0.0019W/m, or 4180W, or a per-passenger consumption of 22kJ, aka 0.006kWh.
I'm sorry, let's back up, what was all this ranting you were doing about the conservation of energy?
I don't know what forums you're used to where you can just make up things and have people believe you, but that doesn't fly here. Tank cars are only tested to a fixed positive pressure. Here's the procedure, spelled out in US law. Here's a table of the pressures for different types of tank cars. DOT-111 cars are for storing nonpressurized liquids, and are thus only tested to the minimum test pressure of 100 PSI, aka 6.9 bar. They are not designed to survive a vacuum (although they do if not heavily compromised - which in the Mythbusters
The big brain am winning again! I am the greetist! Now I am leaving for no particular raisin!