未登录,请登录后再发表信息
最新评论 (0)
播放视频

什么叫做音爆

Why Is A Sonic Boom So Loud?

速度和声音有什么关系呢
What does speed have to do with sound?
如果天空当中没有屏障
And if there ’ s no wall in the sky,
你怎么打破声障呢?
how exactly do you break a sound barrier?
大家好我是DNews的艾米 今天我们来探讨一下速度
Hey guys, Amy here with you on DNews today talking speed!
是速度快的事物而不是容易成瘾的毒品
Fast things. Not drug things.
我们大多数将永远无法超过声速
Most of us will probably never go supersonic.
虽然将旅途时间缩短一半的主意非常有吸引力
Though the idea of cutting travel times in half is so appealing,
但这并不可能
it ’ s not something likely
很快成为司空见惯的事
to become common place anytime soon.
我们先谈谈与它相关的历史吧
But let’s start with a bit of a history lesson.
在19世纪80年代奥地利物理学家恩斯特·马赫
In the 1880s, Austrian physicist Ernst Mach
在研究气体的超音速流动时
was studying the supersonic flow of gases
使用了一种放射性透视的方法
using a shadowgraph when he successfully
成功拍摄到一颗子弹超音速的运行
photographed a bullet traveling faster than the speed of sound.
他的图像展示了子弹
What his images showed was a bullet with a shock wave
前后方各有一个冲击波
in front of it and another one trailing behind it
阐明了空气压缩的现象
a clear proof of the phenomenon of compressibility
这项研究最终开创了一个冠之其名的度量方法:
This research eventually led to the measurements that bear his name:
马赫数反映物体在气体中运行的速度
a Mach number is the ratio of the speed of an object traveling through a gas
与声音在同种气体运行速度的比值
to the speed of sound in that gas.
因为我们从来没有考虑到
Because while we don ’ t think about it,
空气是由分子构成的
air is made up of molecules,
就如其他的物质一样
and like any other physical substance,
这些空气分子可以压缩
those air molecules can compress,
这就形成了冲击波
and when they compress they form shock waves.
正是这些冲击波让子弹飞得更快
It ’ s these shock waves that make flying faster
甚至能超越音速
than the speed of sound such a challenge,
在20世纪40年代飞行员就面对了这样的挑战
and in the 1940s, pilots were coming face to face with this challenge.
这些冲击波使构成他们的空气分子振动
these shock waves vibrate the air molecules they’re made of
当这些分子振动时
and when those molecules vibrate
压缩他们的物质也一起震动
they vibrate whatever is compressing them.
比如高速飞行的飞机
In the case of a fast-flying airplane,
它产生的冲击波会使自身剧烈摇动
the shock waves can shake an airplane hard enough
足以让机身解体
to rip it apart.
20世纪40年代工程师们明确表示
It was clear to engineers in the 1940s
未来的飞行制造业将冲破音速的障碍
that the future of aviation lay beyond the sound barrier,
所以有人想制造
so someone would have to build
一架足够又坚固又快速的飞机
an airplane solid enough and fast enough to break
来冲破这个障碍
through that wall.
Bell飞行器制造公司
It was the Bell Aircraft corporation working on a contract
与美国空军合作
with the US Army Air Force that
一同提出解决方案
devised the solution.
从一颗子弹中找到灵感
Taking design inspiration from a bullet,
Bell公司的工程师们发明了X-1型飞行器
Bell engineers designed the X-1 aircraft
专门打破飞行中压缩空气产生的障碍
specifically to break through that wall of compressed airin the sky.
超音速飞机的问世在飞行业中开创了一个新纪元
The advent of supersonic flight opened a whole new era of aviation
尽管明确要提高马赫数
and though higher Mach numbers
遇到的困难并不一样
don’t come with the same barriers
但每一次提速都要打破主要的技术阻碍
every increase in speed is nonetheless a major technological hurdle
1967年最快的驾驶型飞行器问世
The fastest manned flight on record was set in 1967
配备了NASA的X-15气动喷射器
with the NASA-Air Force X-15,
足以驱动火箭达到巅峰速度6.7马赫
a rocket-powered dart of an aircraft that hit a top speed
即大约4519英里每小时!
of Mach 6.7, which is about 4,519 mph!
但X-15是一个超声学研究工具
But the X-15 was a hypersonics research vehicle.
如今大部分飞行器引擎都无法达到它这样的速度
Most flighter jets today aren’t nearly that fast,
尽管它们是超音速飞行器
though there are supersonic flighters.
军用飞机如F-15雄鹰和
Air Force planes like the F-15 Eagle and
F-22猛禽都是超音速喷气式飞机
the F-22 Raptor are both supersonic fighter jets,
其中F-22甚至可以通过后燃装置达到2马赫
and the F-22 can even hit Mach 2 using afterburners.
但还有另一个与音速有关的困难
But there is another challenge associated with supersonic flight
那就是音爆
and that’s a sonic boom
音爆指一架飞机
The sonic boom is the sound an airplane
在穿过前方形成的压缩空气屏障时
makes when it smashes through that wall of compressed air
发出的声音
that builds up in front of it.
但当飞机达到超音速时音爆不会立刻出现
But the boom doesn ’ t just come once when the plane goes supersonic;
而会一直
it keeps going
伴随着超音速客机
in the wake of that supersonic aircraft.
这就是为什么协和式超音速喷射客机
This is exactly why the Concorde,
这个世界上仅有的超音速客机
the world’s only supersonic passenger plane that flew
从1976到2003年为止都只能实现飞跨海洋的里程
from 1976 to 2003, only ever flew over oceans.
实际上在1973年联邦航空局禁止
In fact, the Federal Aviation Administrationprohibited domestic civil supersonic flight
国内使用超音速客机
over land in 1973.
但这并不表示他们不存在了
But all is not lost!
NASA和它在飞行业的合作伙伴正在寻找
NASA and its aviation partners are looking
一个可接受的噪音大小
into identifying an acceptable loudness level
并致力于研制出所谓的“低音爆”飞行器
and working on so-called “ low boom ”aircraft designs
可以降低音爆的水平
that would reduce sonic boom levels and
并有可能让超音速客机重返江湖
maybe bring back supersonic passenger flights.
但这些研究也还有一些需要完备的地方
But that’s still something to look forwardto down the line.
美国空军也一直在展望未来的发展
And the U.S. Air Force always has its eye on the future, too,
它也是DNews的主要支持者
and it ’ s a big supporter of DNews.
美国的空军一号需要飞行员驾驶和革新的推动
The United States Air Force is powered by Airmen and fueled by innovation.
美国的飞行员每天都要驾驶着它飞行
Every day American Airmen go above and
并打破技术与自身的障碍
beyond to break barriers both professionally and personally
无论它是否在克服贫困后
Whether it ’ s overcoming poverty to become
成为了一个护士和白领或者成为了第一个
a nurse and officer or becoming the first
驾驶雷鸟的女性飞行员 这些飞行员
female Thunderbird pilot. These Airmen are known
都因完成了人们眼中望尘莫及之成就而闻名于世
for doing what was once thought to be impossible
你们曾体验过超音速飞行吗?
Have any of you flown supersonically?
如果有请在下方留言告诉我们感想如何
if so tell us what it was like in the comments below
因为我非常想知道它是怎样的
because I am dying to know what it’s like
如果你没有体验过那么你想吗?
And if you haven’t, do you want to?
告诉我们你的想法同时不要忘记订阅
let us know and don’t forget to subscribe for
更多的每周版每日新闻
more Dnews every day of the week [Music]
感谢收看
Thanks for watching!

发表评论

译制信息
视频概述

音爆的简介与航天飞行器前景安利

听录译者

收集自网络

翻译译者

审核员

审核员 HZ

视频来源

https://www.youtube.com/watch?v=a9Jli0D1uEM

相关推荐