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What won’t work, does? Hyperloop

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Posted by 7j43k on Saturday, November 14, 2020 8:31 PM

tree68

 

 
Electroliner 1935
MY concern is what happens when an anomaly occurs 40 miles from a terminal.

 

Probably along the lines of many tunnels that have an accompanying smaller tube for wiring, etc, and to allow access throughout the tunnel without having to travel in the problem tube.  Such access tubes would likely have surface access at reasonable distances.

 

 

The tube is going to have to be divided into sections, with an airlock between each one.  There will be emergency access doors in the tube.  To use a door, the vacuum in that section will have to be released.  Because there will be the airlocks, the vacuum will not have to be released in the entire tube.  And "pods" in those sections can continue.  Or, of course, return from whence they came.

 

Ed

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Posted by BaltACD on Saturday, November 14, 2020 10:12 PM

7j43k
 
tree68 
Electroliner 1935
MY concern is what happens when an anomaly occurs 40 miles from a terminal. 

Probably along the lines of many tunnels that have an accompanying smaller tube for wiring, etc, and to allow access throughout the tunnel without having to travel in the problem tube.  Such access tubes would likely have surface access at reasonable distances. 

The tube is going to have to be divided into sections, with an airlock between each one.  There will be emergency access doors in the tube.  To use a door, the vacuum in that section will have to be released.  Because there will be the airlocks, the vacuum will not have to be released in the entire tube.  And "pods" in those sections can continue.  Or, of course, return from whence they came. 

Ed

If we are going to have the Hyperloop, operate at high speeds - in addition to vacuum on one side of the vehicle, pressure will be required on the other side of the vehicle, with the vehicle providing a reasonable seal between those forces in the tube in which it is operating.

Case in point on a smaller scale

https://www.youtube.com/watch?v=cqidD7kVnxY

Never too old to have a happy childhood!

              

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Posted by 7j43k on Saturday, November 14, 2020 11:48 PM

BaltACD

If we are going to have the Hyperloop, operate at high speeds - in addition to vacuum on one side of the vehicle, pressure will be required on the other side of the vehicle, with the vehicle providing a reasonable seal between those forces in the tube in which it is operating.

Case in point on a smaller scale

https://www.youtube.com/watch?v=cqidD7kVnxY

 

 

No.

It is not required to have pressure on "the other side of the vehicle" unless you are using that pressure to propel the vehicle.

It is possible to propel a vehicle through a space that is entirely a vacuum.

Think:  "space ship"

 

Ed

 

 

 

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Posted by BaltACD on Sunday, November 15, 2020 7:17 AM

7j43k
 
BaltACD

If we are going to have the Hyperloop, operate at high speeds - in addition to vacuum on one side of the vehicle, pressure will be required on the other side of the vehicle, with the vehicle providing a reasonable seal between those forces in the tube in which it is operating.

Case in point on a smaller scale

https://www.youtube.com/watch?v=cqidD7kVnxY 

No.

It is not required to have pressure on "the other side of the vehicle" unless you are using that pressure to propel the vehicle.

It is possible to propel a vehicle through a space that is entirely a vacuum.

Think:  "space ship" 

Ed

Despite having stayed at a Holiday Inn Experss at some point in the past.  I doubt vaccum alone will provide sufficient propulsive force real world enviornment as the vehicle itself moving through the tube will create a low pressure area behind itself that will create 'drag' against the vacuum that is trying to pull the vehicle ahead.  Space is not limited in scope as the Hyperloop by its very existance on Earth is.

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Posted by 7j43k on Sunday, November 15, 2020 9:37 AM

BaltACD

Despite having stayed at a Holiday Inn Experss at some point in the past.  I doubt vaccum alone will provide sufficient propulsive force real world enviornment as the vehicle itself moving through the tube will create a low pressure area behind itself that will create 'drag' against the vacuum that is trying to pull the vehicle ahead.  Space is not limited in scope as the Hyperloop by its very existance on Earth is.

 

 

 

The reason there is a semi-vacuum* in the tube is to minimize air resistance, not to propel the pod.  That is done with a linear induction motor.

No motor; no go.

 

Note also the ridiculously bad fit of the pod in the tube:

 

 

If it were to be propelled by pressure differential, the fit would have to be MUCH better.

 

Ed

*The support method for the pod comes in two versions.  

In one, the pod uses air bearings to support itself on rails.  There has to be enough air for the compressor on the pod to supply the pressurized air.  The air pressure inside the tube is 0.17% of outside the tube.

The other version is the well-known maglev.

It appears that maglev is currently being used.  

 

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Posted by Electroliner 1935 on Sunday, November 15, 2020 1:24 PM

7j43k
In one, the pod uses air bearings to support itself on rails.  There has to be enough air for the compressor on the pod to supply the pressurized air.  The air pressure inside the tube is 0.17% of outside the tube.

What is the plan to extricate passengers when the "car" gets stuck in the tube. Or are we assuming "NOTHING CAN GO WRONG..GO WRONG...GO WRONG"

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Posted by 7j43k on Sunday, November 15, 2020 3:10 PM

Electroliner 1935

 

 
7j43k
In one, the pod uses air bearings to support itself on rails.  There has to be enough air for the compressor on the pod to supply the pressurized air.  The air pressure inside the tube is 0.17% of outside the tube.

 

What is the plan to extricate passengers when the "car" gets stuck in the tube. Or are we assuming "NOTHING CAN GO WRONG..GO WRONG...GO WRONG"

 

 

 

https://hyperloopconnected.org/2020/06/evacuating-the-hyperloop/

 

 

Ed

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Posted by Electroliner 1935 on Sunday, November 15, 2020 10:42 PM

7j43k
Electroliner 1935 
7j43k
In one, the pod uses air bearings to support itself on rails.  There has to be enough air for the compressor on the pod to supply the pressurized air.  The air pressure inside the tube is 0.17% of outside the tube. 

What is the plan to extricate passengers when the "car" gets stuck in the tube. Or are we assuming "NOTHING CAN GO WRONG..GO WRONG...GO WRONG" 

https://hyperloopconnected.org/2020/06/evacuating-the-hyperloop/ 

Ed

Thanks, that is a little more than I had seen. Sounds possible but I would want to see more specifics about the air locks and spacing, etc. Bean counters could cut corners. 

 

 

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Posted by BaltACD on Sunday, November 15, 2020 11:31 PM

Electroliner 1935
 
7j43k
Electroliner 1935 
7j43k
In one, the pod uses air bearings to support itself on rails.  There has to be enough air for the compressor on the pod to supply the pressurized air.  The air pressure inside the tube is 0.17% of outside the tube. 

What is the plan to extricate passengers when the "car" gets stuck in the tube. Or are we assuming "NOTHING CAN GO WRONG..GO WRONG...GO WRONG" 

https://hyperloopconnected.org/2020/06/evacuating-the-hyperloop/ 

Ed 

Thanks, that is a little more than I had seen. Sounds possible but I would want to see more specifics about the air locks and spacing, etc. Bean counters could cut corners. 

Not just bean counters - construction contractor cut corners too.

Never too old to have a happy childhood!

              

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Posted by 7j43k on Monday, November 16, 2020 10:02 AM

And you can throw in incompetence.

On the plus side, there is little if any government involvment.  Yet.

 

Here's a fun read on another hi-tech rail system:

https://www.latimes.com/california/story/2020-08-10/california-bullet-train-bridge-snafu

 

Ed

 

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