901–910 of 983 posts
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If the tube bursts so wide that the capsule could be ejected from it, the inrush of air would likely be so great that capsules probably wouldn't even make it out. The bigger concern would be that they could decelerate too quickly.
And if the tube breaks behind you, you'd just arrive sooner.
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430 km/h (Aerotrain) vs 1200 km/h (Hyperloop) is a big deal. That is possible with the tube design. Aerotrain operated on the "free air" and that was the reason to lose the competition with TGV.
man, the air cushion behavior at 1200 km/h (speed of sound at normal pressure, and 1.2 Mach at the proposed decreased pressure in the tube) would be a subject of a lot of PhD works. Or in other words - it will be hell of an engineering (stability of the cushion and parasitic oscillations come to mind - that is with respect to compressor created cushion, and in addition to the compressor created air cushion the cushio…
"The capsules travel at 760 mph (1,220 kph, Mach 0.91 at 68 ºF or 20 ºC)"
1200 km/h is still subsonic
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man, the air cushion behavior at 1200 km/h (speed of sound at normal pressure, and 1.2 Mach at the proposed decreased pressure in the tube) would be a subject of a lot of PhD works. Or in other words - it will be hell of an engineering (stability of the cushion and parasitic oscillations come to mind - that is with respect to compressor created cushion, and in addition to the compressor created air cushion the cushio…
I just double-checked the pdf. It says: "The capsules travel at 760 mph (1,220 kph, Mach 0.91 at 68 ºF or 20 ºC)" 1200 km/h is still subsonic
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I just double-checked the pdf. It says: "The capsules travel at 760 mph (1,220 kph, Mach 0.91 at 68 ºF or 20 ºC)" 1200 km/h is still subsonic
Mach value is lower for lower pressure, about 250 m/s for hyperloop proposal
Mach(20 C, 1 atm): 343.051 m/s
Mach(20 C, 0.1 atm): 343.182 m/s
Not much higher, but definitely not lower.
http://www.wolframalpha.com/input/?i=speed+of+sound+in+dry+a...
Unfortunately, it refuses to show Mach(20 C, 0.001 atm), since the lowest supported pressure is 0.098 atm.
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Mach value is lower for lower pressure, about 250 m/s for hyperloop proposal
Wolfram Alpha disagrees. It says: Mach(20 C, 1 atm): 343.051 m/s Mach(20 C, 0.1 atm): 343.182 m/s Not much higher, but definitely not lower. http://www.wolframalpha.com/input/?i=speed+of+sound+in+dry+a... Unfortunately, it refuses to show Mach(20 C, 0.001 atm), since the lowest supported pressure is 0.098 atm.
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Offtopic, but please consider writing some blog posts or articles about your experiences working on nuclear submarines. That just sounds so cool, and while the work is probably dull, I'd nonetheless be fascinated to read some detailed stories.
Unfortunately I walk a very fine line about what is sensitive and what is not. I really couldn't go any deeper than what I posted here.
So thanks for whatever you did in keeping the boats safe (both in design and construction), it was certainly much-appreciated in the Fleet.
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You're still missing the part where it incurred interest, so it wasn't free in the least.
Musk put $40m into Tesla and his stake is worth billions. The people put $465m into Tesla and their stake is worth nothing, after making a paltry $12m in interest. In addition, while Tesla was paying the government 3% on that loan, they were paying Musk 10% on his loans, in effect shoveling government money directly into Musk's account. This is a classic example of socializing the risk while privatizing the profits.…
That said, the interest was low, but it was meant as a public good. Without Tesla, I very much doubt the big car companies would be pushing out their own EVs on nearly as aggressive a timescale.
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Wolfram Alpha disagrees. It says: Mach(20 C, 1 atm): 343.051 m/s Mach(20 C, 0.1 atm): 343.182 m/s Not much higher, but definitely not lower. http://www.wolframalpha.com/input/?i=speed+of+sound+in+dry+a... Unfortunately, it refuses to show Mach(20 C, 0.001 atm), since the lowest supported pressure is 0.098 atm.
There's still a chance that Wolfram Alpha is incorrect; I am unable to prove or disprove that, because I don't know aerodynamics.
http://en.wikipedia.org/wiki/Navier%E2%80%93Stokes_equations
Quote: "The Navier–Stokes equations are also of great interest in a purely mathematical sense. Somewhat surprisingly, given their wide range of practical uses, mathematicians have not yet proven that, in three dimensions, solutions always exist (existence), or that if they do exist, then they do not contain any singularity (smoothness). These are called the Navier–Stokes existence and smoothness problems. The Clay Mathematics Institute has called this one of the seven most important open problems in mathematics and has offered a US$1,000,000 prize for a solution or a counter-example."
> There's still a chance that Wolfram Alpha is incorrect ...
At the moment there is no "correct". It's all based on field observations, numerical modeling, and estimation.
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I wonder what the security checkpoints would be like on the HyperLoop if it ever got built? They are saying capsules could depart 30 seconds apart. Imagine is there was an attack in on of them, with several others travelling at high speed just behind. http://www.bbc.co.uk/news/world-us-canada-23677205 I'm sure there some contingency has been thought of, unfortunately it's just the world we live in these days :(
If they turn off the compressor there's a giant air cushion in front of them and the capsule no longer has air bearings. It probably lands on wheels and can then engage the breaks. A small capsule has low inertia as well. Most likely safer than a train.
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Sounds like he took advantage of an ignorant government. I'd do the same. So did Wall Street, but we got less back from that one.
Why was the government ignorant? They had a loan program to kick-start electric vehicles. One of their loans was largely responsible for the existence of Tesla and its ensuing success. The loan was paid back. Should the government have been more profit-maximizing? Do we want civil servants taking large equity stakes in private companies? We fund research (both directly and through the university system) all the time…
AFAIC Tesla upheld their end of the bargain and society is up by quite a bit. This is in stark contrast to other bullshit that the US government has funded which is wasteful at best. War, war on drugs, war on privacy, bankers, ...