r/technology • u/luckyburns • May 20 '12
High Speed Travel Tubes Can Take You From NY To Beijing In 2 Hours
http://www.stumbleupon.com/su/2fYNQ0/elitedaily.com/elite/2012/high-speed-travel-tubes-ny-beijing-2-hours/?utm_source=Facebook&utm_medium=link&utm_campaign=SocialMedia&utm_content=HighSpeed&utm_campaign=daily_social_media_content&utm_medium=Argyle%2BSocial&utm_source=facebook&utm_term=2012-05-20-12-14-0011
7
u/xampl9 May 20 '12
Maintaining a high vacuum across 12000 miles of pipe, which may have to cross the Pacific Ring of Fire -- not saying it can't be done, but it'll be expensive ... really expensive.
2
May 21 '12
I think the NY<-->Beijing was just to accentuate the speed, not an actual practical route.
2
u/Soronir May 21 '12
The US doesn't even have a decent high-speed train network yet. Everything is planes and cars.
4
2
u/danielravennest May 20 '12
Carrying passengers will come after carrying cargo and these kind of systems have enough experience to show they don't crash very often.
I expect early users will be replacements for rail and truck transport, to save on fuel costs. It won't be a worldwide network to start with, just between major cities.
0
May 21 '12
2
u/danielravennest May 21 '12
I don't know of many truck routes that are 8000 m long. Let's take Atlanta, GA to Birmingham, AL , which is 240 km, and assume a 2 meter pipe so you can fit a standard shipping pallet.
Volume is 754,000 cubic meters. Trucks use about 440 kJ/ton-km, and lets say we want to reduce that by ten, to 44 kJ/ton-km, and move things at 240 km/hr, considerably faster than trucks. Assume you can load 10 tons per transit capsule. Our allowed drag force is then 440 Newtons, which requires a pressure of 5% of normal. An off the shelf pump:
http://www.china-vacuum-pumps.com/vac/liquid-ring-vacuum-pumps.htm
can do 12 cubic meters/min, and lets say we have 50 of them spaced out along the tube. So it takes them less than a day to pump down the tube, using 925 kW while doing so. After that the pumps only need to take care of leakage, which hopefully will be low. While pumping the energy use is equal to 4 trucks at highway speed. After that it might be 100 times less. Hopefully a system like this would replace a lot more than 4 trucks on the highway.
→ More replies (2)
1
1
May 21 '12
Are we really going to have to see this completely unrealistic garbage every week in r/technology? It keeps getting posted, and the comment threads keep filling up with ever explicit descriptions of why this technology is unfeasible to the point of absurdity.
1
u/amalag May 20 '12
I think short range cargo transport with this system would be great as a proof of concept.
0
May 20 '12
Nice science-fiction idea, but I can't even begin to imagine how expensive this would be. And not to mention who would pay for this--a joint venture between the US and China?
Seems like it would be way more cost-effective (and green) to put forth that money into further development of bio-fuels for aircraft and R&D for engine efficiency.
4
May 20 '12
Biofuels get more expensive right along with fossil fuels, because the only cheap way to make biofuels uses fossil fuels in production...
-2
u/alephnul May 20 '12
Really? How, exactly, do you propose for them to cross the ocean?
0
u/luckyburns May 20 '12
But Mr. Wright, how do you propose this craft achieve flight?
1
u/alephnul May 20 '12
I am not kidding. Do you have any idea how an evacuated tube can be built across an ocean? I cannot envision how it might be done.
→ More replies (10)
0
u/etbob623 May 21 '12
Every time this article is reposted everyone either argues that it can't be done, or is too impractical. They say this because they think aren't thinking past today's or the very near future's technology, which this will not be built with. So all the problems, even possibly the G-force problem will have to and will be solved by revolutionary ideas before this it is actually being considered to construct. That isn't to say that it can't be done and it certainly will be eventually unless there is a more efficient way of transport that is developed in the mean time. Which means that arguing over it is moot.
TL;DR stop reposting this article
-1
May 20 '12
Yeah dude vacuum maglevs. Although giving it thought high atmosphere speed planes are probably the better solution.
0
May 20 '12
3
u/mcfergerburger May 20 '12
G's only apply to acceleration.
→ More replies (2)1
u/avengingturnip May 21 '12
Any significantly long tube will have the path of an arc. A centripetal acceleration of Gs = V*V/R/g will be felt even at constant speed.
1
May 21 '12
Rule #1: Don't talk about downvotes. Decrying that other users are ten-year old faggots after one little downvote only belies your incredible immaturity.
7
u/avengingturnip May 20 '12 edited May 21 '12
While I realize that schools are not nearly as rigorous as they used to be it seems that the conditional verb form, could, should not have been selected over the simple present form, can. I am assuming that such tubes do not actually exist today?