NASA令人困惑的发动机难题：英语精读讲义

On the 12th of September 1962,

1962年9月12日，

President John F. Kennedy made his famous speech about landing a man on the moon by the end of the decade. 語法

约翰·F·肯尼迪总统发表了著名的演讲，宣告将在该年代末把人类送上月球。

At this point in time,

在这个时间点，

NASA had just several hours worth of human space flight experience.

NASA（美国宇航局）仅有数小时的载人航天经验。

Many Americans had accepted that the space race would be won by the Soviet Union, 語法

许多美国人已经默认太空竞赛的赢家将是苏联，

who had already claimed the records for launching the first satellite and the first human into orbit.

毕竟苏联已包揽了发射第一颗人造卫星和将第一名人类送入轨道的纪录。

So, in order to achieve their goal of reaching the Moon,

因此，为了实现登月目标，

NASA would need to develop much larger rockets with engines more powerful than anything they had made before.

NASA需要开发更大的火箭，其发动机功率必须超越他们以往制造的任何设备。

But scaling up to a much larger rocket design sent NASA engineers into a new world of complex problems. 短語動詞

但将火箭设计扩展至如此庞大的规模，把NASA工程师推入了一个充满复杂新问题的新世界。

In this video,

在本视频中，

we're going to look at the issues that NASA had with their F-1 engine. 表達脈絡

我们将探讨NASA在其F-1发动机上遇到的问题。

We're also going to look at how they fixed these issues and the unusual method they used to test it.

我们还将了解他们是如何解决这些问题的，以及用于测试的非寻常方法。

In order to lift the enormous Saturn V rocket off the launch pad,

为了将巨大的土星五号（Saturn V）火箭从发射台升空，

it required five F-1 engines on the first stage,

其第一级需要五台F-1发动机，

each capable of producing 1.5 million pounds of thrust.

每台都能产生150万磅的推力。

In order to achieve this amount of thrust,

为了达到这种推力，

massive amounts of RP-1 fuel and liquid oxygen had to be pumped into the thrust chamber. 語法

必须将大量的RP-1燃料和液氧泵入推力室。

Here, the two propellants would combust

在这里，这两种推进剂会燃烧

and lift the Saturn V away from the launch pad.

并将土星五号推离发射台。

The first stage alone would burn through an entire Olympic swimming pool's worth of fuel 講解

仅仅是第一级，就能烧掉相当于整个奥运会标准游泳池容量的燃料，

in just over 2 minutes.

用时仅仅两分多钟。

The company tasked with making such a powerful engine was Rocketdyne. 短語搭配

负责制造如此强大发动机的公司是洛克达因（Rocketdyne）。

They had designed the F-1 engine several years before for the US Air Force,

多年前他们曾为美国空军设计了F-1发动机，

but after the Air Force couldn't find a use for such a powerful engine,

但在空军发现这款强悍发动机无用武之地后，

development was stopped until NASA came along. 短語動詞

开发工作就被叫停了，直到NASA接手。

In June 1962,

1962年6月，

Rocketdyne were ready to perform a long-duration test of the F-1 engine.

洛克达因准备对F-1发动机进行一次长时间测试。

But as the engine ignited and the turbopumps spooled up, 短語動詞

但随着发动机点火和涡轮泵加速，

the test came to a catastrophic end when the engine exploded.

发动机发生了爆炸，测试以灾难告终。

It took several more explosive tests

随后又经历了多次爆炸性的测试，

before the engineers finally found what was going wrong, 語法

工程师们才终于找到了症结所在，

combustion instability. 用詞

即“燃烧不稳定性”。

This is where the propellants in the thrust chamber burn unevenly 語法

这种情况指的是推力室中的推进剂燃烧不均匀，

and cause enormous pressure swings inside the chamber.

在燃烧室内引发了巨大的压力波动。

As one area of the chamber fills with more oxygen,

当燃烧室的某处充入了更多氧气时，

it produces more heat,

就会产生更多热量，

which pushes the flame around in the thrust chamber.

从而在推力室内将火焰推来推去。

The reason this was so catastrophic in the F-1 engine is because these pressure swings were happening 2,000 times a second, 語法

在F-1发动机中这之所以如此致命，是因为这种压力波动每秒发生2000次，

enough to completely rip apart the engine. 短語動詞

足以将发动机彻底撕碎。

At this point,

此时，

the Apollo program was well underway and NASA needed a fully capable engine for the first crewed flights, 短語搭配

阿波罗计划正在全速推进，NASA需要一台功能完备的发动机用于首批载人飞行，

which were just a few years away.

距离飞行只剩短短几年时间。

But since an engine of this scale had never been made before, 語法

但由于这种规模的发动机前所未有，

the solution to this problem wasn't going to be obvious.

解决这个问题的方法绝非显而易见。

Engineers started to focus on the injector plate,

工程师们开始将焦点转向喷注器面板，

which feeds the fuel and oxidizer into the thrust chamber. 短語搭配

它是负责将燃料和氧化剂送入推力室的部件。

The original design was a single large plate with multiple injection holes.

最初的设计是一块带有多个喷射孔的大平板。

Although this was a common design,

尽管这是一种常见设计，

previous engines never suffered from instability

以往的发动机却从未受不稳定性困扰，

since their thrust chambers were much smaller and the propellants were more contained.

因为它们的推力室要小得多，推进剂也更受束缚。

In order to solve this critical issue,

为了解决这个关键问题，

Rocketdyne engineers looked back to one of the very first rocket designs, 短語動詞

洛克达因的工程师回顾了最早的一款火箭设计：

the V-2 rocket. 文化背景

V-2火箭。

This rocket was developed by the Germans during the Second World War,

这款火箭是德国人在二战期间开发的，

but it contained the perfect solution to fix the F-1 engine.

但它包含了修复F-1发动机的完美方案。

Instead of a single flat injector plate,

V-2没有采用单一扁平的喷注器面板，

the V-2 featured several different nozzles,

而是配备了几个不同的喷嘴，

which separated the combustion into different streams.

将燃烧分成了不同的流束。

The engineers believed that the more controlled sections in the V-2 engine

工程师们相信，V-2发动机中更可控的分区

eliminated the possibility of combustion instability.

消除了燃烧不稳定性的可能。

In order to translate this theory onto the enormous F-1 engine

为了将这一理论应用到庞大的F-1发动机上

without a complete redesign,

且无需彻底重新设计，

engineers added a series of baffles to the injector plate 用詞

工程师们在喷注器面板上加装了一系列挡板，

to split the combustion up into different zones. 短語動詞

以便将燃烧分割成不同的区域。

After experimenting with many variations of baffle designs,

在试验了多种挡板设计的变体后，

the engineers came across a layout which seemed to stabilize the combustion. 講解

工程师们发现了一种似乎能稳定燃烧的布局。

The new design was put to the test, 習語

新设计被投入测试，

and sure enough, 表達脈絡

果不其然，

the engine executed a flawless burn. 用詞

发动机实现了完美的燃烧。

But the engineers weren't convinced that the problem was fully fixed. 語氣意圖

但工程师们并不确信问题已被彻底解决。

Many worried that once the engine was in flight,

许多人担心一旦发动机处于飞行状态，

the extra forces and vibrations

额外的受力和振动

could reintroduce instability back into the engine.

可能会将不稳定性再次引入发动机。

So, in order to fully test the new design,

因此，为了对新设计进行充分测试，

NASA placed a small bomb in the center of the injector plate

NASA在喷注器面板中央放置了一枚小炸弹，

and set it off as soon as the engine fired up. 短語動詞

并在发动机点火的同时将其引爆。

The idea was that a small explosion within the engine 表達脈絡

这样做的目的是，发动机内部的微小爆炸

could create an enormous amount of instability,

能制造出极大的不稳定性，

far greater than the engine would naturally receive.

远超发动机在自然状态下承受的程度。

When the bomb went off,

炸弹爆炸后，

the flame inside the engine became completely unstable.

发动机内部的火焰变得极其不稳定。

But almost instantly,

但几乎就在瞬间，

the baffles on the injector plate started to dampen the pressure swings 用詞

喷注器面板上的挡板开始抑制压力波动，

and the combustion became stable again.

燃烧又重新稳定了下来。

NASA performed multiple explosive tests

NASA进行了多次爆炸测试，

in order to make sure that the combustion instability had gone.

以确保燃烧不稳定性已经消失。

From the first Saturn V launch to the last, 表達脈絡

从第一枚土星五号发射到最后一枚，

65 F-1 engines propelled multiple astronauts into space

65台F-1发动机将多名宇航员送入太空，

without any instability problems.

没有发生任何不稳定性问题。

Looking back to a time when rocket engines were designed using slide rules, 講解

回顾那个使用计算尺设计火箭发动机的时代，

the ingenuity that was required to overcome these monumental challenges is spectacular.

克服这些巨大挑战所展现出的独创性令人惊叹。

And although we have yet to return to the Moon, 語法

尽管我们尚未重返月球，

we can appreciate the incredible genius and dedication

但我们依然能感激为了实现肯尼迪的目标

that went into achieving Kennedy's goal. 短語動詞

而投入的非凡智慧与奉献。

Thank you very much for watching

非常感谢您的观看，

and I'll see you in the next video.

我们下期视频再见。