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Sigmetnow

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Re: The Hyperloop
« Reply #200 on: January 27, 2018, 10:04:18 PM »
Feel free to ignore other engineers out there in the real world if you wish. You have repeatedly posted that five year old paper. I've already read it.

Great!
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Re: The Hyperloop
« Reply #201 on: January 27, 2018, 11:23:27 PM »
The city of Chicago struggles to keep all of its streets driveable. The state of Illinois has so much debt, that Moody downgraded its debt rating to Baa3, one level above Junk. We have interstate bridges falling into the Mississippi River. But somehow we are going to find the resources to build a new hyperloop system to replace our inefficient mode of travel. I know it sucks, but the system, beyond a few lines, will never be built.

TerryM

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Re: The Hyperloop
« Reply #202 on: January 27, 2018, 11:36:09 PM »

Musk again:
Quote
Hyperloop Passenger Capsule

The maximum width is 4.43 ft (1.35 m) and maximum height is 6.11 ft (1.10 m). With rounded corners, this is equivalent to a 15 ft2 (1.4 m2) frontal area, not including any propulsion or suspension components.



An oval of 4.43 ft by 6.11 ft has an area of 85.03 ft2., not 15ft2


A pod with a height of 1,1 m would not allow most adults to sit up, even if seated on the floor.


If these actually are Musk's figures, I'm less than impressed.
Terry
« Last Edit: January 27, 2018, 11:48:34 PM by TerryM »

Sigmetnow

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Re: The Hyperloop
« Reply #203 on: January 27, 2018, 11:41:16 PM »
The city of Chicago struggles to keep all of its streets driveable. The state of Illinois has so much debt, that Moody downgraded its debt rating to Baa3, one level above Junk. We have interstate bridges falling into the Mississippi River. But somehow we are going to find the resources to build a new hyperloop system to replace our inefficient mode of travel. I know it sucks, but the system, beyond a few lines, will never be built.

My understanding is that most of the Hyperloop(s) will be built with private money. 
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Sigmetnow

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Re: The Hyperloop
« Reply #204 on: January 27, 2018, 11:48:26 PM »

Musk again:
Quote
Hyperloop Passenger Capsule

The maximum width is 4.43 ft (1.35 m) and maximum height is 6.11 ft (1.10 m). With rounded corners, this is equivalent to a 15 ft2 (1.4 m2) frontal area, not including any propulsion or suspension components.




An oval of 4.43 ft by 6.11 ft has an area of 85.03 ft2., not 15ft2


A pod with a height of 1,1 m would not allow most adults to sit up, even if seated on the floor.


If these actually are Musk's figures, I'm less than impressed.
Terry

Passengers won’t be in the pod long enough to need to get up and walk around — the entire route from San Francisco to Los Angeles will only take 35 minutes.  A semi-recumbent position, for optimal comfort during the ride, has been shown.  In most forms of transport (planes, trains, cars) you would have to pay extra for that!  ;)  ;D
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TerryM

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Re: The Hyperloop
« Reply #205 on: January 27, 2018, 11:51:30 PM »

Musk again:
Quote
Hyperloop Passenger Capsule

The maximum width is 4.43 ft (1.35 m) and maximum height is 6.11 ft (1.10 m). With rounded corners, this is equivalent to a 15 ft2 (1.4 m2) frontal area, not including any propulsion or suspension components.




An oval of 4.43 ft by 6.11 ft has an area of 85.03 ft2., not 15ft2


A pod with a height of 1,1 m would not allow most adults to sit up, even if seated on the floor.


If these actually are Musk's figures, I'm less than impressed.
Terry

Passengers won’t be in the pod long enough to need to get up and walk around — the entire route from San Francisco to Los Angeles will only take 35 minutes.  A semi-reclining position, for optimal comfort during the ride, has been shown.  In most forms of transport (planes, trains, cars) you would have to pay extra for that!  ;) ;D
So you believe his metric figures are correct, and his imperial figures are wrong?
Terry

Sigmetnow

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Re: The Hyperloop
« Reply #206 on: January 27, 2018, 11:55:36 PM »

Musk again:
Quote
Hyperloop Passenger Capsule

The maximum width is 4.43 ft (1.35 m) and maximum height is 6.11 ft (1.10 m). With rounded corners, this is equivalent to a 15 ft2 (1.4 m2) frontal area, not including any propulsion or suspension components.




An oval of 4.43 ft by 6.11 ft has an area of 85.03 ft2., not 15ft2


A pod with a height of 1,1 m would not allow most adults to sit up, even if seated on the floor.


If these actually are Musk's figures, I'm less than impressed.
Terry

Passengers won’t be in the pod long enough to need to get up and walk around — the entire route from San Francisco to Los Angeles will only take 35 minutes.  A semi-reclining position, for optimal comfort during the ride, has been shown.  In most forms of transport (planes, trains, cars) you would have to pay extra for that!  ;) ;D
So you believe his metric figures are correct, and his imperial figures are wrong?
Terry

Looks like the 6 is a typo.

Edit: added image.
« Last Edit: January 28, 2018, 12:01:52 AM by Sigmetnow »
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crandles

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Re: The Hyperloop
« Reply #207 on: January 28, 2018, 12:17:49 AM »

Musk again:
Quote
Hyperloop Passenger Capsule

The maximum width is 4.43 ft (1.35 m) and maximum height is 6.11 ft (1.10 m). With rounded corners, this is equivalent to a 15 ft2 (1.4 m2) frontal area, not including any propulsion or suspension components.

An oval of 4.43 ft by 6.11 ft has an area of 85.03 ft2., not 15ft2

Huh? if rectangular 4.43*6.11 = 27 ft^2 so it has to be less than 27 ft^2 but without looking up area of oval formula, probably by factor of around Pi/4 which would be 21ft^2.

However 1.1m is not 6.11ft more like 3.6 ft so roughly 4.43*3.6*pi/4 = 12.5 ft^2

15ft^2 looks somewhere in the right region, where does 85.03 ft^2 come from????

TerryM

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Re: The Hyperloop
« Reply #208 on: January 28, 2018, 12:27:19 AM »
Your edit convinced me. :)
I drove a tiny sports car for decades that provided similar head room & was quite comfortable. My hair did brush the roof & I'm less than 6ft, but particularly with the top off it made for a comfortable ride. I'm not sure the ADA would approve, but that's fodder for another time.


Was anyone else miffed at the rather unusual units Musk used on his compressor page? Who measures a water pump by the weight of the water moved in one second?, or temperature in K when C fills the bill. Even volumes of air being given values in weight seems odd.
I'd have been interested in the pressure of the steem storage container and recognition that the pod runs out of water in ~45 min.
Terry

TerryM

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Re: The Hyperloop
« Reply #209 on: January 28, 2018, 12:33:13 AM »

Musk again:
Quote
Hyperloop Passenger Capsule

The maximum width is 4.43 ft (1.35 m) and maximum height is 6.11 ft (1.10 m). With rounded corners, this is equivalent to a 15 ft2 (1.4 m2) frontal area, not including any propulsion or suspension components.



An oval of 4.43 ft by 6.11 ft has an area of 85.03 ft2., not 15ft2

Huh? if rectangular 4.43*6.11 = 27 ft^2 so it has to be less than 27 ft^2 but without looking up area of oval formula, probably by factor of around Pi/4 which would be 21ft^2.

However 1.1m is not 6.11ft more like 3.6 ft so roughly 4.43*3.6*pi/4 = 12.5 ft^2

15ft^2 looks somewhere in the right region, where does 85.03 ft^2 come from? ???


OUCH
Looks like I multiplied when I should have added.
Thanks for keeping me honest
Terry


2 stupid math errors in as many months.
Time for a nap.

oren

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Re: The Hyperloop
« Reply #210 on: January 28, 2018, 12:53:17 AM »
Sig, I realize Elon is 100x smarter than me, nor am I an engineer. An d I respect the fact that Elon is trying to replace aviation with an emission-free alternative. I do however believe, using my common sense, that Elon's solution is too complicated, difficult from an engineering perspective, costly, and has a long development time. Even assuming it succeeds, by the time this is ready and fully deployed along hundreds of heavily used aviation routes, we will have fried ourselves many times over. I'd rather see humanity focus on the available and proven technologies (solar, wind, EVs, and some other stuff which is just around the corner. And yes, high speed rails. Even electric planes) and deploy them as widely and quickly as possible, rather than this superbly difficult "craziness" as I see it.

Sigmetnow

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Re: The Hyperloop
« Reply #211 on: January 28, 2018, 01:18:24 AM »
Sig, I realize Elon is 100x smarter than me, nor am I an engineer. An d I respect the fact that Elon is trying to replace aviation with an emission-free alternative. I do however believe, using my common sense, that Elon's solution is too complicated, difficult from an engineering perspective, costly, and has a long development time. Even assuming it succeeds, by the time this is ready and fully deployed along hundreds of heavily used aviation routes, we will have fried ourselves many times over. I'd rather see humanity focus on the available and proven technologies (solar, wind, EVs, and some other stuff which is just around the corner. And yes, high speed rails. Even electric planes) and deploy them as widely and quickly as possible, rather than this superbly difficult "craziness" as I see it.

S’ OK. :)  Give it a year and I think you’ll see significant tunnel progress.  Two or three years and the concept will be up and running, on a few routes, somewhere in the world, quite possibly in the U.S.  And it’s not as though The Boring Company is stopping other progress from going forward.  Electric cars/trucks/buses, electric planes, electric ‘loops will all be taking a bite out of fossil fuel transportation; at first slowly, then exponentially.  Remember, graph lines for new tech adoption increase along an ‘S’ curve!
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Bob Wallace

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Re: The Hyperloop
« Reply #212 on: January 28, 2018, 02:00:47 AM »
There are multiple independent companies working on the Hyperloop concept.  One of the is designing for a pod with roughly the interior space of a regional jet.  Four across seating with a narrow aisle and room for an 'if you must' toilet.

Before people get all worked up over the interior space why don't we wait to see if it works?

Maybe it won't. 

If it doesn't then maybe Boring Co. will create a really fast subway system which would replace short flights and lots of surface travel. 

Maybe batteries will improve enough so that we can fly using electricity.

numerobis

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Re: The Hyperloop
« Reply #213 on: January 28, 2018, 05:08:53 AM »
None of the projects is using the air-cushioned concept. That was a nice idea that avoided the extremely high cost of a maglev. Instead, the projects are all using a maglev.

It’s a nice engineering challenge but it’s not infeasible on technical grounds. Where it seems dubious is the claim it’ll somehow be cheap — when maglevs are already rare due to their cost premium over high speed rail, never mind long evacuated tubes with a maglev inside.

I suspect the way to decarbonize air travel will instead be high-speed rail for short distance travel between major centres (up to 1000 km or so), electric aircraft for short hops that can’t be easily done by rail (due to terrain or small population), and carbon-neutral liquid-fuel for long distances.

Bob Wallace

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Re: The Hyperloop
« Reply #214 on: January 28, 2018, 05:17:49 AM »
Quote
I suspect the way to decarbonize air travel will instead be high-speed rail for short distance travel between major centres (up to 1000 km or so), electric aircraft for short hops that can’t be easily done by rail (due to terrain or small population), and carbon-neutral liquid-fuel for long distances.

I think that's the worst case solution.  It should work.  Now to find  better solutions....

Rob Dekker

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Re: The Hyperloop
« Reply #215 on: January 28, 2018, 06:26:49 AM »
I think I have made my opinion about Hyperloop clear enough, and I agree with oren that it is "bat shit crazy".

Still, I'd like to add something positive :

They power their compressor from a battery. I think Elon in his white paper accounts for a battery that weighs 4,000 kg. Also, that battery would need to be changed (and recharged) after each one-way ride.

I wonder why they don't run electric wires through the tunnel, with current collectors similar to what high speed rail does. That would eliminate 4,000 kg from the pod weigh, which makes it easier to levitate, and would eliminate the need for battery handling at start and stop stations.

Also, if you have electricity from outside, you could also use it for propulsion. Just put the 'rotor' (a piece of aluminum) in the tube, and the 'stator' (with its electromagnets) in the pod.

That should be much more cost effective that Elon's design where the electro magnets are in the tube, spread out over 2.5 km every 50 miles or so.

And it also eliminated that 'jolt' in the ride every 5 minutes or so.

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Re: The Hyperloop
« Reply #216 on: January 28, 2018, 08:54:18 AM »
I realize Elon is 100x smarter than me
No, the maximum Mensa score is 162 and people like Einstein and Hawking are estimated to be at 160. Then you would be at 1.62 and wouldn't be able to write in here. Or by using the average, Elon would be at 980.  ;D

I'm unable to assess any of that, he certainly provides some smart quotes for everyone.
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Re: The Hyperloop
« Reply #217 on: January 28, 2018, 12:35:42 PM »
Tried to find some data on HTT's Vibranium™ but failed.  :-\


http://www.priestmangoode.com/wp-content/uploads/2017/09/HYPERLOOP-PRESS-RELEASE.pdf
Quote
HTT’s passenger capsule will be manufactured using Vibranium™, a proprietary material developed by HTT to ensure passenger safety. HTT is manufacturing the capsule in collaboration with Carbures S.A. (MaB: CAR), who is a leading expert in fuselage and advanced materials construction in both aeronautics and aerospace sector. Carbures S.A. began construction of HTT’s Passenger Capsule earlier this year. The final specs for the capsule are:
Length: 30 meters (98.5 feet)
Diameter: 2.7 meters (9 feet)
Weight: 20 tons
Passenger capacity: 28-40
Speed: Up to 1223 km/h (760 mph)

The designs will accommodate between 28-40 passengers, but the exact configuration of the Hyperloop capsules will vary depending on the needs of the individual carrier. The cabin interior will include large dynamic display virtual windows in the side panels and ceilings, to provide passenger information, and will also incorporate entrance areas, passenger accommodation for food and beverage services, as well as toilets.

https://www.filepicker.io/api/file/zVFkVl4uRICbPSnfFaZM
Quote
Made of sensor-embedded carbon fiber, this new smart material is eight times stronger than aluminum and 10 times stronger than steel alternatives, and transmits critical information regarding temperature, stability, integrity and more, wirelessly and instantly. It is also much lighter in weight—roughly five times less than steel and 1.5 times less than aluminum—reducing energy output to propel the capsule.

The Hyperloop Vibranium capsule construction was also revealed, showing the material in a dual-layer sandwich formation. This allows for complete passenger safety even if the outer skin is damaged. The material communicates issues immediately and the Hyperloop capsule would be taken out of circulation for maintenance. This technology is one of the first technologies HTT has developed in conjunction with top Slovakian companies.

To develop Vibranium HTT contracted with Slovakian collaborator C2i, a company that intelligently engineers carbon-fiber structures for next-generation cars and aircrafts. “With HTT and other Slovakian scientists we helped develop Vibranium, a new smart material, which is the perfect solution to build a safe system,” said C2i founder Patrick Hesel. “The challenges shown by the Hyperloop System are a perfect fit for the technical know-how available in Slovakian automotive, new material, and production processes.”

Cute name though, I would've preferred adamantium, Logan is nominated for an Oscar:
https://movieweb.com/logan-movie-oscar-nomination-best-adapted-screenplay/
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numerobis

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Re: The Hyperloop
« Reply #218 on: January 28, 2018, 03:14:29 PM »
I wonder why they don't run electric wires through the tunnel, with current collectors similar to what high speed rail does. That would eliminate 4,000 kg from the pod weigh, which makes it easier to levitate, and would eliminate the need for battery handling at start and stop stations.

Moving current into the train creates a fair bit of drag and friction even with high-speed rail. I gather they're worried it wouldn't be viable at 3x the speed (drag would be no worse but friction would be).

If induction charging becomes viable for the necessary currents, that would be one way. High-speed rail is already looking into that kind of trick.

ghoti

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Re: The Hyperloop
« Reply #219 on: January 28, 2018, 07:20:36 PM »
I wonder why people constantly suggest power is better supplied externally for transport. Battery power is already cost effective and much more flexible. Batteries are improved steadily at lower cost every year so they become a better and better option.

People seem to forget that running wires everywhere you want transport is very expensive, makes expanding routes cumbersome, and provide very little benefit.

SteveMDFP

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Re: The Hyperloop
« Reply #220 on: January 28, 2018, 08:07:45 PM »
For trips of up to, say, 30 minutes, I wonder if it could be worth eliminating all the complexities and simply use vacuum in front of the pod, and atmospheric pressure behind it.   One would use parallel air pumps along the way to re-establish vacuum.  For this use, you'd want a narrow tube, like Musk's Boring company creates. 

This idea was put into use in the 19th century
Crystal Palace pneumatic railway
https://en.wikipedia.org/wiki/Crystal_Palace_pneumatic_railway

So proof-of-concept was done a century and a half ago.  We have technology to make it better and faster now.

Bob Wallace

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Re: The Hyperloop
« Reply #221 on: January 28, 2018, 09:17:53 PM »
For trips of up to, say, 30 minutes, I wonder if it could be worth eliminating all the complexities and simply use vacuum in front of the pod, and atmospheric pressure behind it.   One would use parallel air pumps along the way to re-establish vacuum.  For this use, you'd want a narrow tube, like Musk's Boring company creates. 

This idea was put into use in the 19th century
Crystal Palace pneumatic railway
https://en.wikipedia.org/wiki/Crystal_Palace_pneumatic_railway

So proof-of-concept was done a century and a half ago.  We have technology to make it better and faster now.

That would be the Strong Tailwind Model?

A parallel smaller diameter tube/tunnel where air is evacuated ahead of the pod and moved to behind the pod.  Might mean less frequent pods or pods moving in packs.  Something like the pod train leaves every half hour.

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Re: The Hyperloop
« Reply #222 on: January 28, 2018, 09:27:22 PM »
Sig, I realize Elon is 100x smarter than me, nor am I an engineer. An d I respect the fact that Elon is trying to replace aviation with an emission-free alternative. I do however believe, using my common sense, that Elon's solution is too complicated, difficult from an engineering perspective, costly, and has a long development time. Even assuming it succeeds, by the time this is ready and fully deployed along hundreds of heavily used aviation routes, we will have fried ourselves many times over. I'd rather see humanity focus on the available and proven technologies (solar, wind, EVs, and some other stuff which is just around the corner. And yes, high speed rails. Even electric planes) and deploy them as widely and quickly as possible, rather than this superbly difficult "craziness" as I see it.


This is spot on. Our situation is critical and time is short. Any solution that cannot be implemented quickly, piggybacking on our existing infrastructure, is pointless even if technologically feasible.

This is why LED lightbulbs, installed in every existing socket, is better than a technology that requires the wholesale replacement of sockets.

The biggest obstacle to the wholesale adoption of EV's is not the cost or the technology but the lack of infrastructure to charge them. Not insurmountable but it delays adoption. The advantage of EV's with regards to existing infrastructure is they use a road system that has taken a century to build.

Bob Wallace

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Re: The Hyperloop
« Reply #223 on: January 28, 2018, 10:28:10 PM »
Quote
Any solution that cannot be implemented quickly, piggybacking on our existing infrastructure, is pointless even if technologically feasible

Going underground with the Hyperloop (assuming it works) is probably faster and cheaper than high speed rail in many places.

Surface tracks would mean a lot of problems with right of way securement.  Lots and lots and lots of lawsuits unless the government was willing to go very heavy handed with eminent domain.

High speed rail would mean fencing off swaths of land on each side of the track, building a rail bed, dealing with crossing roads, streams, and changes in terrain.    Tunneling would simply go under all those problems.

Standard tunnel boring speed 60 feet per day (average).  Musk says that Boring can operate at 14x standard.  Let's use 600 feet per day (10x improvement, a bit more conservative than Musk’s 14x).

3,000 miles coast to coast.  200 10x-tunneling machines could complete a coast to coast tunnel in half a year. 

Open 100 entry holes.  Insert one machine at each end and two in all other openings (one headed east and one west).  Half a year and the tunnel is dug.

Snatch out the tunneling machines and start boring hub routes.

TerryM

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Re: The Hyperloop
« Reply #224 on: January 28, 2018, 11:21:18 PM »

No, the maximum Mensa score is 162 and people like Einstein and Hawking are estimated to be at 160. Then you would be at 1.62 and wouldn't be able to write in here. Or by using the average, Elon would be at 980.  ;D

I'm unable to assess any of that, he certainly provides some smart quotes for everyone.


Sorry, but there is no "maximum Mensa score". Minimum score is 132, but most of the self selecting membership is higher. Scores in the 145 to 185 range are not terribly unusual.
Terry


Bob Wallace

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Re: The Hyperloop
« Reply #225 on: January 29, 2018, 12:06:27 AM »

No, the maximum Mensa score is 162 and people like Einstein and Hawking are estimated to be at 160. Then you would be at 1.62 and wouldn't be able to write in here. Or by using the average, Elon would be at 980.  ;D

I'm unable to assess any of that, he certainly provides some smart quotes for everyone.


Sorry, but there is no "maximum Mensa score". Minimum score is 132, but most of the self selecting membership is higher. Scores in the 145 to 185 range are not terribly unusual.
Terry

Also, once scores get outside the +/-1 standard deviation range they aren't very reliable.  IQ tests have many more items in the midrange so chance plays a larger role as one moves towards the extremes.

Furthermore, you can't put a meaningful number on intelligence.  A number that will predict future success.  There are  different kinds of 'intelligence'.  Some people can have excellent memory but not be as good at assembling facts into useful forms.  Others may be excellent problem solvers but because of not as good memory may have to reinvent the wheel each time they work on a problem.  Depending on the task those two types of individuals may be much differently "intelligenced".

Rob Dekker

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Re: The Hyperloop
« Reply #226 on: January 29, 2018, 05:36:27 AM »
I wonder why people constantly suggest power is better supplied externally for transport. Battery power is already cost effective and much more flexible. Batteries are improved steadily at lower cost every year so they become a better and better option.

No doubt. Batteries have made great progress. But they are still heavy and in this (Hyperloop) they affect the entire system. Remember that in Elon's design, the batteries cannot provide power for propulsion. So he planned putting electromagnets in the tube, rather than in the pod. If you were to put electromagnets over the full 600 km of the ride it would be cost prohibitive, so instead he puts them every 60 km or so. That causes a 'jolt' of 0.5 g every 5 min or so, which could be considered very uncomfortable for the riders, especially for the Vibranium capsule that Speedy pointed out above, where people can move around and go to the bathroom and such.

If there were power lines inside the tube, and current collectors on the pod, all of that can be avoided. The ride would be nice and smooth, the cost of electromagnets in the pod alone (instead of 2.5 km stretches of them every 60 km) would be far lower, and the friction that the current collectors impose would be minor compared to the power use of the vacuum pumping system.

[edit] Let me just add that I still think the whole idea of Hyperloop is bat shit crazy.
You are essentially flying a space craft through a gun barrel, hovering 1 mm above solid metal. Anything goes wrong and the entire system fails, killing everyone inside the tube.
« Last Edit: January 29, 2018, 05:49:51 AM by Rob Dekker »
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Re: The Hyperloop
« Reply #227 on: January 29, 2018, 07:19:27 AM »

No, the maximum Mensa score is 162 and people like Einstein and Hawking are estimated to be at 160. Then you would be at 1.62 and wouldn't be able to write in here. Or by using the average, Elon would be at 980.  ;D

I'm unable to assess any of that, he certainly provides some smart quotes for everyone.


Sorry, but there is no "maximum Mensa score". Minimum score is 132, but most of the self selecting membership is higher. Scores in the 145 to 185 range are not terribly unusual.
Terry
Noticed the grin? If I were to be serious, I would've added that the test in question was the Cattell III B test. The maximum score is 162 for those under 18.
To be honest, I couldn't care less for the mensa tests, I once had a collegue who was a very proud mensa member.   :-X
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Re: The Hyperloop
« Reply #228 on: January 29, 2018, 07:23:15 AM »
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I once had a collegue who was a very proud mensa member.

I once worked with three who bragged about their membership.  And none were the brightest bulbs on the tree.


TerryM

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Re: The Hyperloop
« Reply #229 on: January 29, 2018, 08:30:48 AM »
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I once had a collegue who was a very proud mensa member.

I once worked with three who bragged about their membership.  And none were the brightest bulbs on the tree.


Be careful of the DK!


Being proud of a Mensa intellect is like taking pride in being tall. It's there, it's who you are, but you did nothing to attain it. The very tall have their groups,  and Mensa can be thought of as a self help group for the congenitally bright.


132 interestingly is where IQ and wealth separate and go of on their disparate paths. Below that magic mark wealth and intelligence are in lockstep. Above 132, the brighter you are, the less likely you are to attain great wealth. Hence the often heard "If you're so bright, how come you ain't rich?"


Back in 2012 I came out of the closet when I asked for help with a presentation I was making at the Annual Gathering of Canadian Mensa. Thanks in large part to the help I received from Neven's followers it was very successful.
I take some pride in that presentation. I take pride in having headed the Southwestern Ontario Mensa group for many years, but I take no more pride in having been born a Mensan than I do in having born white, or to wealthy parents.


Terry

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Re: The Hyperloop
« Reply #230 on: January 29, 2018, 11:43:38 AM »
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Be careful of the DK!
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Aiming for first flight of Falcon Heavy on Feb 6 from Apollo launchpad 39A.
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Bob Wallace

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Re: The Hyperloop
« Reply #231 on: January 29, 2018, 05:22:02 PM »
Quote
I once had a collegue who was a very proud mensa member.

I once worked with three who bragged about their membership.  And none were the brightest bulbs on the tree.


Be careful of the DK!


Being proud of a Mensa intellect is like taking pride in being tall. It's there, it's who you are, but you did nothing to attain it. The very tall have their groups,  and Mensa can be thought of as a self help group for the congenitally bright.


132 interestingly is where IQ and wealth separate and go of on their disparate paths. Below that magic mark wealth and intelligence are in lockstep. Above 132, the brighter you are, the less likely you are to attain great wealth. Hence the often heard "If you're so bright, how come you ain't rich?"


Back in 2012 I came out of the closet when I asked for help with a presentation I was making at the Annual Gathering of Canadian Mensa. Thanks in large part to the help I received from Neven's followers it was very successful.
I take some pride in that presentation. I take pride in having headed the Southwestern Ontario Mensa group for many years, but I take no more pride in having been born a Mensan than I do in having born white, or to wealthy parents.


Terry

Let me add, I've worked with dozens of people who were obviously smarter than the three Mensa members I know/knew.  None of those extremely bright people ever mentioned any desire to be a Mensa member.   

The very bright people I have known were mainly motivated by learning more, not by obtaining more. 

As an undergraduate I took a statistics course in the university business school.  The 'intelligence' of the business students was clearly lower than that of the science students with whom I spent most of my time.  (That's not to say that there was no overlap.)  I suspect the business students went on to acquire a lot more wealth than the science students.

Motivation probably separates us out early in our lives.  If you want to be rich then you go into business, or perhaps medicine.  If you want intellectual stimulation you go into science or another field which requires continual learning and thinking but doesn't pay well.  If you want to help people then you go into social work, nursing, or perhaps medicine.


Sleepy

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Re: The Hyperloop
« Reply #232 on: January 29, 2018, 08:40:40 PM »
Who has the bigger footprint, Ape or Man?

Who is the smartest?
Joan Pick:
https://www.mamensa.org/2008/11/13/the-mensan-woman-with-a-tiny-carbon-footprint/
Quote
I adopt a [lifestyle] that is consistent with the sustainable management of the world’s resources. Everyone knows we have to have very severe cutbacks to meet that standard
Quote
It seems a bit joyless to me (where are the treats?), but Pick isn’t a joyless person; far from it – she’s delightful. I’ve made her late for her daily two-hour run. We walk down the several flights of stairs together (she never uses the lift) and she runs off into the afternoon sunshine.
Or Elon Musk (to get on topic again ;) ):
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Sigmetnow

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Re: The Hyperloop
« Reply #233 on: January 29, 2018, 09:32:02 PM »
... Any solution that cannot be implemented quickly, piggybacking on our existing infrastructure, is pointless even if technologically feasible.
...

Why?  Hyperloops implemented any time in the next five to ten years will be taking hundreds or thousands of cars a day — ICE cars, since EVs will still be a smaller percentage of all vehicles — off the road, thus lowering emissions.  A hyperloop can be powered with clean energy.

Elon has said the first section of the Los Angeles tunnel should be complete in “about a year.”  Make that 3 years for Elon time.  ;)  That’s a whole lot of emissions poised to be saved — not just in the car trips avoided, but in the reduced traffic tie-ups for the vehicles that are still on the roads near the ‘loop.

Edit: 
Note: The Los Angeles tunnels will apparently be using skate/sled transport, not a vacuum hyperloop.  Passengers and bicyclists, etc. will ride in people pods.
« Last Edit: January 30, 2018, 02:57:45 PM by Sigmetnow »
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Re: The Hyperloop
« Reply #234 on: January 30, 2018, 08:46:22 AM »
... Any solution that cannot be implemented quickly, piggybacking on our existing infrastructure, is pointless even if technologically feasible.
...

Why?  Hyperloops implemented any time in the next five to ten years will be taking hundreds or thousands of cars a day — ICE cars, since EVs will still be a smaller percentage of all vehicles — off the road, thus lowering emissions. 
We already know how to remove one hundred thousand cars without building anything, from Stockholm:

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Sigmetnow

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Re: The Hyperloop
« Reply #235 on: January 30, 2018, 02:55:04 PM »
...
We already know how to remove one hundred thousand cars without building anything, from Stockholm:
...

Super glad those congestion tolls worked for Stockholm.  Try it in Los Angeles and... you’d be sorry.  Geography, economy, lack of other transit options... completely different.  Thus LA’s solution must be different, too.
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Re: The Hyperloop
« Reply #236 on: January 30, 2018, 04:36:13 PM »
...
We already know how to remove one hundred thousand cars without building anything, from Stockholm:
...

Super glad those congestion tolls worked for Stockholm.  Try it in Los Angeles and... you’d be sorry.  Geography, economy, lack of other transit options... completely different.  Thus LA’s solution must be different, too.
LA? Ah, noticed that you added LA to your previous post after you wrote your latest comment.
I can understand that it's different in different cities. But people are not that different, in my opinion. A lot of people just did not travel at all during rush hours in Stockholm, after the tolls were introduced. Did you watch the video? Adding an image from that section, when asked, they didn't know what they did.

LA seems to show the same resistance as in Stockholm.
https://la.curbed.com/2017/10/13/16467386/congestion-pricing-los-angeles-explained
Their mobilty plan seems to solve some of the public transports. No hyperloop mentioned in that paper: https://losangeles2b.files.wordpress.com/2015/02/appendix-b1-mobility-2035.pdf

More or less the same resistance seems to be found in New York. But they are soon there?
http://www.tstc.org/congestion-pricing-an-analysis-of-new-york-state-legislative-districts/
Quote
While congestion pricing by itself won’t solve every transportation challenge our city faces, it is an integral part of a larger strategy to make urban transportation more efficient, sustainable and equitable. Our recent report, A Way Forward for New York City: Road Pricing in London, Stockholm and Singapore, demonstrates that other cities with congestion pricing programs invested in mass transit improvements before enacting congestion pricing and, crucially, dedicated revenues from congestion pricing directly to public transit improvements. If New York is to have the same success with congestion pricing, we must invest in public transit fixes now and with congestion pricing revenues as well.

After the tolls were implemented in Stockholm, the resistance dropped and people started supporting them. Image two also from the video above.
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Sigmetnow

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Re: The Hyperloop
« Reply #237 on: January 30, 2018, 06:23:06 PM »
But Stockholm had 500,000 trips a year?  Ha!  One road, Interstate 405, in LA had 374,000 a day — and that was ten years ago!  It’s congested pretty much all day long, so time-shifting won’t help.  Try another route?  LA has six of the top ten worst traffic corridors in the U.S. —and the 405 didn’t even make that list. 

http://www.laweekly.com/news/traffic-on-the-405-isnt-that-bad-really-6716813

Yes, I watched the video. You did not mention the solution was congestion pricing when you gave the link.
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Sigmetnow

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Re: The Hyperloop
« Reply #238 on: January 30, 2018, 06:40:28 PM »
Quote
...Road Pricing in London, Stockholm and Singapore, demonstrates that other cities with congestion pricing programs invested in mass transit improvements before enacting congestion pricing.

No reason tunnels can’t be part of those ‘improvements before congestion pricing.’  Obviates most of the problems of gaining right-of-way for rail and affecting surface roads and existing traffic.  Main objections until recently were cost and time required to build tunnels.  The Boring Company is working on that.  With their own money, I might add.  (Well, and the money from selling Boring Company hats and flamethrowers. ;) )

When travellers have choices, then you can encourage them to use a less congestive option.
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magnamentis

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Re: The Hyperloop
« Reply #239 on: January 30, 2018, 07:49:47 PM »
Who has the bigger footprint, Ape or Man?

Who is the smartest?
Joan Pick:
https://www.mamensa.org/2008/11/13/the-mensan-woman-with-a-tiny-carbon-footprint/
Quote
I adopt a [lifestyle] that is consistent with the sustainable management of the world’s resources. Everyone knows we have to have very severe cutbacks to meet that standard
Quote
It seems a bit joyless to me (where are the treats?), but Pick isn’t a joyless person; far from it – she’s delightful. I’ve made her late for her daily two-hour run. We walk down the several flights of stairs together (she never uses the lift) and she runs off into the afternoon sunshine.
Or Elon Musk (to get on topic again ;) ):

i believe that really smart (speak wise) people cannot be filthy rich and wouldn't spend all there time for business/making money.

dunno how many know the saying with the camel and the needle eye, just mentioning it to point any readers thoughts into the direction i mean here.

there were many other renown "among the smartest/wisest that were famous for the modest life style ( diogenes for one at least as the saying goes )

then there is something called "physiognomy" not saying much more ;)

sometimes i can't avoid the idea that someone is digging a multi billion dollar grave with unsupported walls, only that before the walls ( think card house) will collapse the idols are untouchable/glorified for/by too many and i'm not talking private wealth, he should be safe but i'm sure we gonna hear one day about who's paying for all the losses or "à fond perdus" projects.

should this have sounded like if i dislike those projects i have to rectify that impression but i as well don't think it's smart/wise to glamorize single entities and/or to put someone on a pedestal. history has proven what happened later with a quota that is too close to  100% to be ignored.
« Last Edit: January 30, 2018, 08:03:05 PM by magnamentis »

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Re: The Hyperloop
« Reply #240 on: January 30, 2018, 08:15:58 PM »
Main objections until recently were cost and time required to build tunnels.  The Boring Company is working on that.  With their own money, I might add.
Good that they use their own money over there. Low employment and stuff like that made the city of Salo in Finland invest 100000 euros in the hyperloop promises as a part of that link between Helsinki and Stockholm. And that's taxpayers money.

Quote
But Stockholm had 500,000 trips a year?  Ha!  One road, Interstate 405, in LA had 374,000 a day — and that was ten years ago!  It’s congested pretty much all day long, so time-shifting won’t help.  Try another route?  LA has six of the top ten worst traffic corridors in the U.S. —and the 405 didn’t even make that list. 

Maybe you forgot where this started?
... Any solution that cannot be implemented quickly, piggybacking on our existing infrastructure, is pointless even if technologically feasible.
...

Why?  Hyperloops implemented any time in the next five to ten years will be taking hundreds or thousands of cars a day — ICE cars, since EVs will still be a smaller percentage of all vehicles — off the road, thus lowering emissions.  A hyperloop can be powered with clean energy.
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Re: The Hyperloop
« Reply #241 on: January 30, 2018, 09:16:03 PM »
i as well don't think it's smart/wise to glamorize single entities and/or to put someone on a pedestal. history has proven what happened later with a quota that is too close to  100% to be ignored.
History is always wise to consult when it comes to us humans.
Did you listen to this from the BBC?
https://forum.arctic-sea-ice.net/index.php/topic,1094.msg140143.html#msg140143
Anita Sengupta said that everything is on track for the first commercial operation in 2021 with 700mph or 1127km/h. The hyperloop history is not that far away.
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Re: The Hyperloop
« Reply #242 on: January 30, 2018, 09:42:49 PM »
But Stockholm had 500,000 trips a year?  Ha!  One road, Interstate 405, in LA had 374,000 a day — and that was ten years ago!  It’s congested pretty much all day long, so time-shifting won’t help.  Try another route?  LA has six of the top ten worst traffic corridors in the U.S. —and the 405 didn’t even make that list. 

Maybe you forgot where this started?
... Any solution that cannot be implemented quickly, piggybacking on our existing infrastructure, is pointless even if technologically feasible.
...

Why?  Hyperloops implemented any time in the next five to ten years will be taking hundreds or thousands of cars a day — ICE cars, since EVs will still be a smaller percentage of all vehicles — off the road, thus lowering emissions.  A hyperloop can be powered with clean energy.

I just rewatched the “sled/skate” video.  It shows cars going through the tunnel about one a second.  (I vaguely remember a Musk comment to that effect, also.) That would mean up to about 86,400 cars a day.  Times two directions, 172,800.  With two tunnels in each direction, that’s about 345,600.  Hey, the 405 could be empty!  ;) ;D  JK. Would still have lots of trucks.  Until they add cargo pod sleds....

But it’s not just counting cars.  The smaller-than-a-bus-or-train “people pods,” which go quickly and directly to your destination without intermediate stops, and which are bicycle-, wheelchair- and stroller- friendly, should be a big hit as a new form of “mass transit,” as well!
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Re: The Hyperloop
« Reply #243 on: January 30, 2018, 10:00:52 PM »
Without Hype'loop it's like the Jetsons without the jet.  ;D
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Re: The Hyperloop
« Reply #244 on: January 30, 2018, 10:01:38 PM »
For business trips my wife travels by train here in Calif. We have tried to forgo all air transport even though that means extra days for every trip. She has however been stuck on the tracks several times because either the train she was on or another somewhere on the same track hit a pedestrian. This week a pedestrian fatality added eight more hours to what would have been a six hour trip. The conductor on the train said it has become a weekly occurrence in the LA area. I have a feeling death by train is becoming a suicide option.
 I have traveled by high speed rail in Japan and Europe and most of the tracks are well fenced or elevated. Maybe the hyper loop is the only way intercity high speed rail is ever going to happen around here. Sometimes the 405 feels like a game of Russian roulette even when it's moving because shoving all those cars down six lanes at 75 mph is just plain nuts ! If the hyper loop ever starts running it will be worth a few extra bucks to avoid the crazy stress that LA freeways always produce. It used to be kinda fun in a mini cooper 40 + years ago but the thrill is gone. I'm getting way too old to enjoy the
Hellhole LA has become .
 

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Re: The Hyperloop
« Reply #245 on: January 30, 2018, 10:53:47 PM »

A friend had brought back video she'd taken of a HSR in China, and one of the things that
impressed me was the length of the train. It appeared to be at least a mile long, possibly some multiple of that.
Sleepy's video mentions that the advantage of the Hyperloop system is that it lowers air resistance.


Doesn't each car in a HSR train, with the exception of the lead car, share the air resistance of that lead car?
Wouldn't a 3 car train have ~ the same air resistance as a single car or a 10 car train?
While it wouldn't allow a HSR to operate at higher speeds, it certainly would allow a long HSR to operate with much lower energy usage per passenger mile than a one or two car unit.


Wouldn't compatible enclosed freight cars, running perhaps behind, but attached to the high speed passenger cars, be running at energy costs comparable to low speed freight since the air resistance has been dealt with by the lead car?


Drive to the station in Hong Kong and load your vehicle in an auto transport car. Relax in a sleeper car to awaken in London, or Delhi, with your Tesla S in tow.
Perhaps you manufacture cars or widgets in Hong Kong and a rush order comes in for a dozen from London or Delhi. Drop them at the local station knowing they'll be at their destination by the following business day.


Is this what the New Silk Road will be offering to everyone up and down the line(s)?
Will the Hyperloop be competitive when the costs of moving HSR passengers is offset by the fees paid by the freight cars following behind?



Terry

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Re: The Hyperloop
« Reply #246 on: January 31, 2018, 04:05:39 AM »
”Today, the Missouri Hyperloop Coalition announced an agreement between Virgin Hyperloop One, the University of Missouri System, and the global engineering firm Black & Veatch to move forward with an in-depth feasibility study for an ultra high-speed hyperloop route along the I-70 corridor between St. Louis and Kansas City. The route would turn the economic power of the state’s two largest metro areas and the University of Missouri System into an interlinked economic powerhouse in the Heartland of the U.S.”

Missouri Is One Step Closer to a Hyperloop with In-Depth Feasibility Study
https://hyperloop-one.com/blog/missouri-one-step-closer-hyperloop-depth-feasibility-study

Hyperloop One says KC to St. Louis is a top 5 route, begins closer study
http://kansascity.com/news/business/article197419809.html

Virgin Hyperloop One Announces the Next Region for Feasibility Study
The United Arab Emirates, the Netherlands, Colorado, and now ... Missouri.
https://www.inverse.com/amp/article/40668-missouri-hyperloop-study
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Sigmetnow

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Re: The Hyperloop
« Reply #247 on: January 31, 2018, 04:28:40 AM »
...
Doesn't each car in a HSR train, with the exception of the lead car, share the air resistance of that lead car?
 ...
Terry

The aero-drag on the lead car is only one aspect of the train’s drag.  The air turbulence between each car, and under each car, are also a factor.  (The Tesla semi-truck has moveable “wings” attached to the back of the cab, to conform a smooth shape to any trailer it may haul, and is very smooth underneath to minimize that drag.)

But beyond air drag is the force required to move the weight of the train, and overcome the friction of the wheels.  Long freight trains require several locomotives — much more power — to move all that weight.  The benefits of the hyperloop pod (if handled right ;) ) is the physics of running in a near vacuum, rather than through air, and a suspension system that becomes almost frictionless at speed, allowing the pod to coast long distances at high velocity with only an occasional “push” — meaning much less energy is required.
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Rob Dekker

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Re: The Hyperloop
« Reply #248 on: January 31, 2018, 05:07:56 AM »
Doesn't each car in a HSR train, with the exception of the lead car, share the air resistance of that lead car?
Wouldn't a 3 car train have ~ the same air resistance as a single car or a 10 car train?
While it wouldn't allow a HSR to operate at higher speeds, it certainly would allow a long HSR to operate with much lower energy usage per passenger mile than a one or two car unit.

That sounds right. Air friction per unit length reduces with length.
That's also why High Speed Rail is one of the most energy efficient forms of transportation :



Quote
Wouldn't compatible enclosed freight cars, running perhaps behind, but attached to the high speed passenger cars, be running at energy costs comparable to low speed freight since the air resistance has been dealt with by the lead car?

There are also rolling losses. They simple increase with length of the train.
And you can't extent the length of a train indefinitely.
Lateral forces during curves and length of stations and such.
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Rob Dekker

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Re: The Hyperloop
« Reply #249 on: January 31, 2018, 05:44:26 AM »
But beyond air drag is the force required to move the weight of the train, and overcome the friction of the wheels.  Long freight trains require several locomotives — much more power — to move all that weight.  The benefits of the hyperloop pod (if handled right ;) ) is the physics of running in a near vacuum, rather than through air, and a suspension system that becomes almost frictionless at speed, allowing the pod to coast long distances at high velocity with only an occasional “push” — meaning much less energy is required.

I agree with most of what you are saying, but with a couple of side notes :

Air friction (and thus energy usage) increases with the square of speed of the train.
So if you want to go twice the speed as HSR, you increase energy use due to air friction by a factor of 4. Hyperloop wants to mitigate that by reducing the air density, but this goes only linearly. So if you want to go twice the speed, and keep air friction the same, you have to reduce air density by a factor of 4 (go to 250 mb).

The problem is that creating lower pressure also demands energy. Especially when compensating for leaks. The NASA paper that Sleepy posted previously :
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20170001624.pdf

gives a good overview of when it makes sense to put the train in a tube, and which pressure it should operate on to be more energy efficient than simply building a HSR system. See fig. 12.
This suggests that yes, it makes sense to lower the pressure in the tube, but it may not be energy efficient to operate it at the near-vacuum conditions, and ultra-high speeds, that Elon originally anticipated.

And then there is the issue of the pod cross area versus the tube cross area, which puts essentially an upper limit on the speed you can run the pod at (at least without resorting to exotic new technologies like putting a large vacuum pump in front of the pod running at 10X the RPMs of a jet engine).

My guess as an engineer is that the first real commercial Hyperloop (if it would be built at all) would be a traditional MagLev running at speeds less than 300 mph inside a tube at reduced pressure but not near vacuum.
« Last Edit: January 31, 2018, 05:49:54 AM by Rob Dekker »
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