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为什么飞机上的窗户是圆形的? – 译学馆
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为什么飞机上的窗户是圆形的?

Why are plane windows round?

Why are airplane windows round?
为什么飞机窗户是椭圆形的?
This seems like a simple question,
这个问题看上去似乎很简单
but let’s take a look.
但让我们来探究一下答案
As passenger planes became more popular,
随着民用飞机的普及
planes needed to fly higher.
飞机需要飞得更高
Flying higher means less drag,
更高的高度意味着更少的摩擦力
because the air density is lower in the upper atmosphere,
因为高层大气的空气密度较低
so less fuel is wasted.
因此油耗会更少
Flying high also means a more comfortable flight,
高空飞行也意味着更加舒适的飞行体验
because the plane can now fly above the turbulent lower atmosphere.
因为飞机现在可以避开下层大气的乱流
But some design changes need to be made to allow this,
但为了实现高空飞行 需要对飞机设计进行一些修改
First, the cabin has to be pressurized
首先 客舱需要密封加压
to create a survivable environment for the passengers,
给旅客提供必要生存环境
second, the cabin must be cylindrical in shape,
其次 客舱需要是圆柱形的
because a cylinder can resist the new internal pressure,
因为圆柱形可以抵抗新产生的内部压力
but one design flaw was not corrected
但当客舱最初引进加压系统时
when cabin pressurization was first introduced,
还有一个设计缺陷未被纠正
the windows remained square,
就是方形的窗户
so why is this a problem?
为什么它会产生问题呢?
As a plane increases in altitude,
随着飞机爬升高度
the external atmospheric pressure lowers more than the internal cabin pressure.
外部大气压力低于机舱内部压力
This creates a pressure difference between the inside and outside of the plane,
这造成了飞机内外的压力差
causing the plane to expand ever so slightly.
导致极其细微的膨胀
When a material change is shaped like this,
当材料发生这种变形时
stress is created in the material,
材料内部也会产生应力
as the material is stretched more and more if the stress begins to rise.
随着材料拉伸的加剧 应力也随之上升
Eventually, the stress can rise so high that the material breaks,
最终 这种应力可以升高到使材料断裂
and there are a lot of factors that can elevate this stress,
影响应力的因素有许多
one of them is the shape of the material.
其中之一就是材料的形状
In planes, the shape of the windows has huge effect on the level of stress.
在飞机上 窗户的形状对应力水平有着巨大的影响
Stress will flow smoothly through material,
应力可以在材料中平滑地流动
but if an obstacle is placed in its path,
但当流动路径上有障碍物时
like a window,
比如一个窗户
it needs to change direction,
它就需要改变方向
and this causes the pressure to build in certain locations.
这就导致了应力在某点聚积
This is called stress concentration.
这叫做“应力集中”
Comparing modern-day oval windows and square windows,
对比现代椭圆形窗户与方形窗户
you can see that the square windows provide a larger barrier to the smooth flow of stress,
可以看到 方形窗户给应力平滑流动造成了更大的障碍
and this means that the stress builds in the sharp corners of the window.
这意味着应力在窗户边角处聚积
This elevated stress created by the square windows
这种方形窗户造成的应力升高
actually caused cracks to form in the de Havilland comet
导致了哈维兰彗星客机形成裂纹
causing three tragic crashes.
引发了三起坠机惨剧
The investigations that followed led to our a greater understanding of stress concentration
事故随后进行的调查使我们更加了解了“应力集中”效应
and that is why all plane windows are now oval in shape.
而这就是现在的飞机窗户都是椭圆形的原因

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为什么呢?

听录译者

survivor

翻译译者

Finn

审核员

审核员 D

视频来源

https://www.youtube.com/watch?v=7rXGRPMD-GQ

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