Chinese experts comment on Thomas g super high speed rail: all stop at the ideas stage-super high-speed rail, high speed rail-IT information
Recently, the media was buzzing with news-"faster than the plane of super high speed train is coming," attracted the attention of countless followers.
According to the United States NBC business channel (CNBC) recently reported that startup Hyperloop super high-speed propulsion system One outdoors for the first time the test is successful, 3-metre-long experiment "pulley" in run on paved tracks for 2 seconds, the final speed of 400 miles per hour (about 640 km/h), hit 91 miles of sand and stop.
Reports also pointed out that, if in the final scenario, super high-speed trains will travel in a sealed vacuum or low pressure ducts, maximum 760 miles per hour (about 1230 km/h).
If the invention of the airplane to achieve human-like birds "fly" the dream, then this almost 1 time times faster than the plane of "crazy", "rocket", if you can make people dream come true?
1230 km/h, the mean straight-line distance was shortened from Beijing to Shanghai in less than an hour, this leading to shock.
As we all know, three prizes are today's fastest high-speed rail HSR sweep, China's high-speed rail operation has been far behind after the rest of the world. Speed of 300 kilometers per hour is not only China's rail "myth", it became high iron objects of worship in the world.
Railways "fly" has been the people's imagination, but with the tracks carrying trains can reach amazing speed like a space launch vehicles God? High-speed rail is there a speed "ceiling"?
"This is the United States tested its own rocket propulsion, rather than rail. Up to 640 kilometers per hour, not the train's speed, just rocket thrusters in orbit to start. "Tongji University urban rail and Railway Engineering Department Director, Zhou shunhua told the China Science News reporter, railway operations are carrying passengers, Max acceleration scientific limitations, rather than fantasy.
Sun Quanxin transportation College, Beijing Jiaotong University Professor also pointed out: "it's just a theory for a long time, but very far from reality, all just stop at the ideas stage. ”
For the advance of technology and scientific limitations, Zhou shunhua, high-speed vertical acceleration cannot exceed one meter by seconds squared, acceleration does not increase too quickly. He noted that the speed increase too quickly may cause a problem, this is not for rail transport to take.
" If you reach that speed on the ground, now the most difficult issue is not ground friction coefficient, difficult mainly due to air resistance. On this point, it is impossible to achieve such speed on the science . "Sun Quanxin said.
In addition, Zhou shunhua also stressed that in the near future, want to achieve this rate and there is no possibility that China railway 300 km per hour has reached a very high level, so there's no need to do this without scientific basis of "crazy" ideas.
So, if out of orbit, vacuum piping environment, as well as bullets fired car pop like a capsule, technology can solve it?
Sun Quanxin said, but another had to face the reality, vacuum how to solve? " If you run in the thousands of kilometers, in case of a loss of vacuum, what will be the consequences? How can we fully realize in the thousands of kilometers of vacuum? To address these technical problems will not be easy . ”
Vacuum problem once solved, will face with respect to the matter of perception, this Sun Quanxin think nothing more difficult. "As well as aircraft, installed inside the train slowed down the glass, my wife feels not too dramatic. ”
中国专家评马斯克超级高铁：一切只停留在奇思妙想阶段 - 超级高铁,高铁 - IT资讯
近日，被媒体吵得沸沸扬扬的一则新闻——“比飞机还要快的超级高铁要来了”吸引了无数关注者的目光。
据美国全国广播公司财经频道(CNBC)近日报道，创业公司Hyperloop One的超级高铁推进系统首次户外测试成功，3米长的实验“滑车”在铺设好的轨道上运行了2秒钟，最终速度达到400英里每小时(约合640公里/小时)后，撞击到了91米外的沙堆才减速停车。
报道还指出，如果按照最终设想，超级高铁将在密闭真空管道或低压管道中行驶，时速最高可达760英里(约合1230公里/小时)。
如果说飞机的发明实现了人类像鸟一样“飞翔”的梦想，那么这种比飞机还要快近一倍的“疯狂”的“地面火箭”，是否可以让人类再次梦想成真呢？
1230公里/小时，意味着从北京到上海的直线距离被缩短在了一小时内，这不得不让人震撼。
众所周知，当今最快高铁的冠亚季军均被我国高铁包揽，中国高铁运行水平已经远远把世界其他国家抛在脑后。每小时300公里的速度不仅是中国铁路的“神话”，更成为了世界高铁膜拜的对象。
让铁路“飞”一直是人们的想象，但以轨道承载的高铁是否可以达到像空间发射器上天一样的惊人速度呢？高铁是否有速度“上限”呢？
“这次是美国在测试自己的火箭推进器，而不是铁路。每小时能达到640公里，并不是高铁速度，只是人们将火箭推进器在轨道上开动而已。”同济大学城市轨道与铁道工程系主任周顺华告诉《中国科学报》记者，铁路的运行目的是承载旅客，其最高运行加速度有一定科学限制，而不是想入非非。
北京交通大学交通运输学院教授孙全欣也同样指出：“这只不过是很早以前就有的一个理论，但距离现实还非常遥远，一切只停留在奇思妙想阶段。”
对于技术的超前性和科学上的限制，周顺华表示，一般高铁的纵向加速度不能超过一个米秒平方，加速不能加到太快。他指出速度加到太快会出问题，这种速度根本不是轨道交通所能承受的。
“在地面上如果达到这种速度，现在最难解决的还不是地面的摩擦系数问题，难度主要源于空气阻力。就这一点来说，科学上是不可能实现如此速度的。”孙全欣说。
此外，周顺华还强调，在不远的未来，想要达到这种速度也没有任何可能性，他认为中国铁路的300公里每小时已经达到了非常高的运行水平，所以并没有必要做这些没有科学依据的“疯狂”设想。
那么，如果摆脱了轨道，在真空的管道环境中，如同子弹发射一样将车厢像胶囊一样弹出，技术瓶颈就能迎刃而解吗？
孙全欣表示，这却带来了另一个不得不面对的现实问题，真空该如何解决？“如果在几千公里的运行中，万一一个地方失去真空，后果将怎样？我们又该如何在几千公里中完全实现真空？解决这一系列的技术难题并非易事。”
真空问题一旦解决，又将面临车内人的感受问题，这一点孙全欣倒认为没什么难度。“就如同飞机一样，如果车厢内部安装减速玻璃，车内人的感受不至于太过剧烈。”