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  (Source: Shutterstock)
U.S. is left in the dust as China blazes ahead with $1T USD rail bid

America may be witnessing its descent into the twilight in terms of being on the bleeding edge of transportation technology.  This week China, the world's most populous nation opened the world's longest stretch of high-speed rail.

Linking the capital city of Beijing in the north with the southern city of Guangzhou, the 2,298 kilometer (1,428 mile) line has already began ferrying passengers at 300 kilometers per hour (186 mph).  The line will cut the fastest travel time between the cities from around 20 hours to only 8 hours, making it a day trip.

150 pairs of trains (300 total) will run daily along the line, which passes through the provincial capitals cities Shijiazhuang, Wuhan and Changsha.  

The rail line was not achieved without setbacks.  The bullet train project's supervisor, the former railway minister, and the ministry’s chief engineer were both detained in a corruption probe after a bullet train crash killed 40 people in mid-2011 and after a section of track in central China collapsed under heavy March rains.  China had to rebuild some of the line and slow test runs after finding corrupt contractors had used subpar building materials to construct sections of the track.

China rail launch
Chinese dignataries gather to celebrate the launch of the world's longest stretch of high-speed track. [Image Source: The Washington Post]

China, however, is not looking to let off the gas. It will have four major east-west lines, and three more major north-south lines by 2020, linking virtually every major city in China.  While the U.S. and other economic rivals initially expressed skepticism of China's ambitious rail plans -- which are expected to cost around $1T USD -- China has already achieved roughly half of its 18,000 kilometer goal for 2015, with 9,300 km (5,800 miles) of active high-speed track.

The Asian giant is also testing next-generation trains, which it hopes will travel at around 310 miles per hour, once again cutting travel time roughly in half.

The U.S., whose massively socialist national highway project was once perhaps the world's most ambitious and well-engineered transportation conduits, has balked at the proposal of a high-tech replacement for its aging government-owned roadways.  And the private sector in the U.S. has expressed precious little interest in such a project, due to the price and low profit potential.

China bullet train
One of the new bullet train hurtles down the track. [Image Source: Shutterstock]

It's hard to say for sure just how big an economic boost high speed rail will provide China, but it's expected to bring radical new opportunities to the nation.  To relate in U.S. terms, high speed rail would make commutes from Detroit to Chicago, Pittsburgh and New York City feasible for those willing to spend up to a few hours of their lives a day in transit possible, opening new job opportunities.

The U.S. has some high speed rail plans of its own, but the billions put forth by the Obama administration have been dwarfed by China's commitment, as have the program's respective successes.  With the activation of the Guangzhou and Beijing bullet train conduit, one has to wonder whether we are witnessing the passing of the technological torch from the U.S. to China, and what the economic impact of that leadership transition will be.

Sources: The Washington Post, Shutterstock



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RE: Image
By ritualm on 12/27/2012 7:38:25 PM , Rating: 3
You can go 180 mph in a long shipping container. Whether doing that will be comfortable, stable and safe is another question.

The angled front isn't there to look pretty, it is there to reduce aerodynamic drag at high speeds, and it is important if you want the train to stay in one piece while moving that fast over long distances.


RE: Image
By 91TTZ on 12/28/2012 11:29:30 AM , Rating: 2
quote:
The angled front isn't there to look pretty, it is there to reduce aerodynamic drag at high speeds, and it is important if you want the train to stay in one piece while moving that fast over long distances.


You missed the point where I addressed that:

"The sharply angled front of the new bullet train makes it look fast, but in reality that shape isn't needed for the relatively slow speeds that a train travels. The need for swept-back surfaces really only arises when you start getting close to the speed of sound."

That long, angled front is mostly for looks. A more blunt, rounded shape like the other picture is more aerodynamically efficient at subsonic speeds. Those principles of aerodynamics were figured out over a hundred years ago.

Take a look at the shape of the front of a DC-3. Notice how blunt and rounded it is. It first flew in 1935 and has a max speed of 230 mph :

http://www.atpm.com/12.06/eea-airventure/images/Pr...

Here's the front of a 767-400ER. It's also blunt and rounded. It went into service in 2000 and has a max speed of about 560 mph:

http://www.flickr.com/photos/25695066@N00/63479253...

Now here is the front of the Concorde. It first flew in 1969 and has a max speed of Mach 2. The sharply angled shape is necessary because it cruises at supersonic speeds:

http://members.shaw.ca/johniuchi/Concorde_3.jpg

Here is a .45 ACP bullet from a .45 automatic pistol. The bullet travels at subsonic speeds for most of its flight, so a blunt, rounded shape is again the most efficient. This is from 1906.

http://en.wikipedia.org/wiki/File:45_ACP_-_FMJ_-_S...

This is a .30-06 Springfield bullet from a rifle. The bullet travels at supersonic speeds for most of its flight so a sharply tip is again the most efficient shape. This bullet is also from 1906.

http://www.underwoodammo.com/images/products/detai...

I hope my pictures helped explain the fact that the sharply angled front of this train is not aerodynamically necessary and is mostly there to make it look fast. It evokes memories of supersonic jets, bullets, and missiles. However, at the speeds it travels (about 200 mpg) a blunt shape would be more efficient.


RE: Image
By yomamafor1 on 12/28/2012 4:12:12 PM , Rating: 2
quote:
That long, angled front is mostly for looks. A more blunt, rounded shape like the other picture is more aerodynamically efficient at subsonic speeds. Those principles of aerodynamics were figured out over a hundred years ago.


Uh... no its not. It's there for functional purpose. The angled front divert the air upward, to 1. facilitate minimal air resistance, and 2. to transition from rounded nose to square sized cars in the most efficient way.

Let's see what the Japanese, who builds the best high speed trains, have come up with.

http://www.aidan.co.uk/md/JpKtNozomi5902.jpg
http://www.railwaygazette.com/typo3temp/pics/cb1da...


RE: Image
By 91TTZ on 12/29/2012 10:29:12 AM , Rating: 3
The reason why this particular Chinese bullet train looks like that particular Japanese bullet train is because they copied its design.

The FASTEST trains in the world need to have a more aerodynamic shape, and the most aerodynamically efficient shape for subsonic speeds is a more blunt, rounded nose. I know it doesn't look as exciting but it's actually more efficient.

Here is the world's fastest conventional trainset. Note its blunt, rounded nose:
http://en.wikipedia.org/wiki/Siemens_Velaro

Here is the world's fastest operational train, the Chinese Shanghai Transrapid maglev. Also note its blunt, rounded nose:
http://home.wangjianshuo.com/archives/2003/08/09/s...

Here is the train that set the world's record for a train at over 350 mph, the French TGV. Note its blunt, rounded nose:
http://www.ibabuzz.com/transportation/2007/04/04/3...
http://dodevice.com/wp-content/uploads/2007/04/tgv...

I know it's a boring shape, but again, it's the most aerodynamically efficient shape at subsonic speeds.

What about cars? When Bugatti wanted to create the world's fastest road car they realized that a blunt, rounded shape was the most aerodynamically efficient for subsonic speeds, so they went with that:
http://gomotors.net/pics/Bugatti/bugatti-veyron-16...

However the Bloodhound SSC will be supersonic, so it's going to need a long, sharply tapered design:
http://www.nasa.gov/images/content/617017main_45s_...

What about missiles?

Some missiles cruise subsonically like the Tomahawk cruise missile. Again, a blunt, rounded shape is the most efficient:
http://upload.wikimedia.org/wikipedia/commons/5/55...

What if you wanted to make a supersonic cruise missile like our old Regulus? Then you'd have the sharply pointed shape:
http://www.air-and-space.com/20061202%20Pt%20Mugu/...

This isn't me just trying to justify what I want, these are fundamental laws of aerodynamics. They are well understood and no longer being debated.


RE: Image
By PrinceGaz on 12/28/2012 4:44:51 PM , Rating: 2
The whole reason why trains are so efficient at transporting things is because they
a) have very little rolling-resistance due to using steel wheels on steel rails
b) the aerodynamic drag is minimal compared with other energy usage

Your 4,000 ton diesel-hauled freight train trundling along at 40 mph can have every single truck shaped like a brick and it will make no noticeable difference to efficiency. In fact that is probably more efficient at packing in the maximum number of containers.

Your 400 ton electric-powered 200 mph passenger service is an altogether different story. Energy is used to accelerate, and recovered (fed back into the overhead wires) whilst braking. The overall energy usage depends almost entirely on how much energy needs to be spent maintaining a high speed, and that is determined by how much rolling-resistance and aerodynamic drag it experiences.

The rolling-resistance is always far lower than aerodynamic-drag in high-speed trains, which is why every high-speed train for the last few decades has been streamlined. With speeds in the 150-200mph range this is more important than ever, and once you get to 200mph+ it becomes absolutely critical to performance.

A long pointy nose might not be viable on a plane for weight (weight == fuel usage on planes) and weight-distribution reasons, but a couple of extra tons on the front of a train costs nothing compared with the rest of the weight and can help it cut through the air that bit more efficiently.

Don't judge how trains should look by how planes do.


RE: Image
By 91TTZ on 12/29/2012 11:32:01 AM , Rating: 2
In my reply above to the other poster I gave more examples of the most aerodynamically efficient shapes. It doesn't matter if these shapes are used on a car, truck, train, plane, or missile. The point in all these examples is to move air around the body of the vehicle while creating the least drag possible.

quote:
Your 4,000 ton diesel-hauled freight train trundling along at 40 mph can have every single truck shaped like a brick and it will make no noticeable difference to efficiency. ... Your 400 ton electric-powered 200 mph passenger service is an altogether different story... The overall energy usage depends almost entirely on how much energy needs to be spent maintaining a high speed, and that is determined by how much rolling-resistance and aerodynamic drag it experiences.


In my train examples, I didn't point out a freight train and claim that that's an efficient shape. I used the FASTEST trains as examples where aerodynamics count. The simple fact remains that at subsonic speeds a blunt, rounded nose is more aerodynamically efficient than a sharply angled and tapered nose. This has been understood for a very long time.

For instance, take a look at an old streamliner steam engine from the 1930's. This train is the world record holder for steam locomotives. It has a very familiar shape, with the leading edge similar to the leading edge on most high speed trains:
http://en.wikipedia.org/wiki/File:Number_4468_Mall...

quote:
A long pointy nose might not be viable on a plane for weight (weight == fuel usage on planes) and weight-distribution reasons, but a couple of extra tons on the front of a train costs nothing compared with the rest of the weight and can help it cut through the air that bit more efficiently. Don't judge how trains should look by how planes do.


I think I did a good job pointing out when a long, tapered nose is aerodynamically efficient. It becomes the most aerodynamically efficient shape when the object is going at or faster than the speed of sound. For speeds much below that a blunt, a rounded shape is the most efficient.

You claim that airliners don't have long, pointy noses because it's too heavy. This is entirely false. They do it because having a long, pointy nose on a subsonic object is aerodynamically inefficient. Even subsonic bullets have the familiar blunt, rounded shape. They're meant to be heavy, so they're made out of lead. Yet they still choose the familiar blunt nose because it's the most efficient shape at those speeds.

There is a reason that you don't see subsonic airliners being shaped like the Concorde with a long, pointy shape- It's simply not efficient at subsonic speeds.

Why is it that supersonic aircraft suddenly are able to have pointy noses while subsonic aircraft do not?
Why is it that supersonic cars (see Bloodhound SSC) suddenly are able to have pointy noses while subsonic cars do not?
Why is it that supersonic missiles are able to have pointy noses while subsonic missiles are not? Does weight suddenly not matter to them? No, it's because at supersonic speeds a long, pointy nose becomes the most aerodynamically efficient shape. At subsonic speeds a rounded, blunt nose is the most aerodynamically efficient.

The information we're discussing is all over the place and I can't believe that people would even take the time to disagree with me when the information is all over the place. They could spend that time learning and afterwards they'd agree with me.


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