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Hyperloop

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Re: Hyperloop

#72
post #64

From my skimming of the PDF, it sounds like a pneumatic tube transportation system with a compressor fan on the front of the vehicle that moves high-pressure air from the front to the back maintaining a low-pressure state around the vehicle. Kind of like an Earth-bound Alcubierre drive.

Does it support multiple pods in the tube at once?

Yes but they need to be 5 miles apart so they would board approximately every 30 seconds and carry 28 people each.

Re: Hyperloop

#73
post #59
post #32

"In the case of the Hyperloop, Musk started focusing on public transportation after he grew disenchanted with the plans for California’s high-speed rail system." And who says that big government stifles entrepreneurial innovation? If ALL Musk does with the Hyperloop announcement is shed more light on the potential debacle that is to be our $70b+ high-speed rail in California, we owe him a debt of gratitude. PS - Dire…

So, we have "light shed" on the current "debacle" and neither system gets built. That's a win? HSR was first commerically available in 1964. Yes, it got really expensive waiting 50 years. I imagine it'll be even more expensive in another 20-30. California is going to get even more crowded.

Not building the HSR that is envisioned is the win.

Re: Hyperloop

#74

The key advantages of a tube vs. a railway track are that it can be built above the ground on pylons and it can be built in prefabricated sections that are dropped in place and joined with an orbital seam welder. Did anyone else read this and imagine laser beams fired by satellites?

Not really. It's a valid welding http://en.wikipedia.org/wiki/Orbital_welding), but I imagine it might be quite a task to scale it up to pipes as large as would be needed for this project.

Re: Hyperloop

#75

So, it's a two-lane highway where the cars are 5 miles apart? How many people will be able to use this thing?

From the report: "...with capsules departing as often as every 30 seconds from each terminal and carrying 28 people each. This gives a total of 7.4 million people each way that can be transported each year on Hyperloop."

Re: Hyperloop

#76
post #59
post #32

"In the case of the Hyperloop, Musk started focusing on public transportation after he grew disenchanted with the plans for California’s high-speed rail system." And who says that big government stifles entrepreneurial innovation? If ALL Musk does with the Hyperloop announcement is shed more light on the potential debacle that is to be our $70b+ high-speed rail in California, we owe him a debt of gratitude. PS - Dire…

So, we have "light shed" on the current "debacle" and neither system gets built. That's a win? HSR was first commerically available in 1964. Yes, it got really expensive waiting 50 years. I imagine it'll be even more expensive in another 20-30. California is going to get even more crowded.

That's an argument in favor of a useful HSR system. But politics have resulted California's HSR system being deliberately pessimized; it may do more harm than good to the HSR cause, right?

Re: Hyperloop

#78
post #64

From my skimming of the PDF, it sounds like a pneumatic tube transportation system with a compressor fan on the front of the vehicle that moves high-pressure air from the front to the back maintaining a low-pressure state around the vehicle. Kind of like an Earth-bound Alcubierre drive.

Does it support multiple pods in the tube at once?

Yes, a pod would depart every 2 minutes or less, which puts about 23 miles between them.

Re: Hyperloop

#79
post #64

From my skimming of the PDF, it sounds like a pneumatic tube transportation system with a compressor fan on the front of the vehicle that moves high-pressure air from the front to the back maintaining a low-pressure state around the vehicle. Kind of like an Earth-bound Alcubierre drive.

Does it support multiple pods in the tube at once?

Yes, but no discussion of how you'd bring the system down if one broke down mid-trip or how you'd bring it back up. The individual cars only carry power to maintain speed, no to accelerate, so if they have to stop because something goes wrong, a whole bunch of people are stuck in the middle of nowhere without a toilet (or air?)

Re: Hyperloop

#80

The aerodynamic power requirements at 700 mph (1,130 kph) is around only 134 hp (100 kW) with a drag force of only 72 lbf (320 N) Mind blown.

But that's at a pressure of 100Pa (1/1000 atm). How much power does it take to maintain a vacuum of 1/1000atm in a tube hundreds of miles long? It seems this point is skipped over in the whitepaper, so perhaps its negligible.

Edit: yes I was referring to the power to sustain a vacuum in a leaky system, of course no power is required to maintain a vacuum in a perfectly sealed system :)

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