脉冲爆震发动机

帅哥

[size=+1]什么是脉冲爆震发动机？

One of the newest and most exciting areas of pulse-jet development is the Pulse Detonation Engine (PDE).

对脉冲的最新和最激动人心的领域之一射流发展是脉冲爆震发动机（PDE）的。

While they work on similar principles to a regular pulsejet, the PDE has one very fundamental difference -- it detonates the air/fuel mixture rather than just allowing it to simply deflagrate (burn vigorously).

虽然他们在类似的原则工作提高到一个定期pulsejet，PDE的一个很根本的区别-它引爆的空气/燃料，而不是只允许它只是爆燃混合物（燃烧积极）。

[size=+1]Detonation versus Deflagration

[size=+1]爆轰与爆燃

Deflagration is what happens when you burn a mixture of air and fuel at reasonably low pressure.

爆燃时会发生什么是刻录在合理的低压力的空气和燃料的混合物。

The "woof" you get when igniting a dish of flammable liquid such as gasoline is a deflagration.

在“纬”，当你点燃一盘易燃液体，如汽油是一种爆燃。

Deflagration is, believe it or not, a relatively gentle process which is simply the rapid burning the fuel.

爆燃是，不管你信不信，一个相对平缓的过程，仅仅是迅速燃烧的燃料。

When we cause an air/fuel mixture to deflagrate in a semi-enclosed space (such as a pulsejet or auto-engine) then pressure is generated and that pressure can be harnessed to perform some work -- eg: create thrust or turn a crankshaft.

当我们造成空气/燃料混合物爆燃的半封闭空间（如pulsejet或汽车发动机），那么产生的压力，压力可以用来执行一些工作-例如：创建推力或转曲轴。

One of the primary attributes of deflagration is that the flame travels at a speed significantly lower than the speed of sound.

对爆燃的主要特征之一，是火焰的速度大大低于音速的降低旅行。

Detonation however is a far more powerful reaction of the air/fuel mixture and results in such a rapid reaction that the pressure-wave created travels at super-sonic speeds.

不过是爆轰的空气变得更加强大了反应/燃料混合物，在这种快速反应的压力波产生的超音速的速度旅行的结果。

In effect, detonation is a violent explosion and as such it produces vastly higher pressures than the simple burning process of deflagration.

实际上，爆炸是一次剧烈爆炸，因此它产生比简单爆燃燃烧过程中的压力大大增加。

Obviously, when we're looking to produce thrust, the more pressure we can generate within an engine the better -- that's why researchers are trying to build pulsejets that detonate their fuel charge rather than just burn it in a deflagrating reaction.

显然，当我们正在寻找产生推力，在更大的压力，我们可以在一个发动机产生更好-这就是为什么研究人员正试图建立pulsejets该引爆的燃油附加费，而不仅仅是在爆燃烧伤的反应了。

[size=+1]Turning Deflagration into Detonation

[size=+1]谈到爆燃到爆震

So how do you go about turning a comparatively gentle deflagration reaction into a detonation?

那么如何去要成为一个较为温和的爆炸爆燃反应？

One important component of triggering a detonation is pressure.

其中引发了爆炸的重要组成部分，是压力。

It is much easier to detonate a mixture of air and fuel if it is highly compressed prior to (or during) the ignition process.

这是非常容易引爆的空气和燃料如果是高度压缩之前（或期间）点火过程的混合物。

Unfortunately, conventional pulsejets don't create enough pressure to produce detonation. In fact the level of compression created within a regular pulsejet engine is very low, even by automobile standards.

不幸的是，传统的pulsejets不产生足够的压力，产生爆炸。事实上范围内定期pulsejet引擎创建的压缩程度很低甚至汽车标准。

Think of a pulsejet as having a compression ratio (CR) around 2:1 or less -- whereas your car probably has a CR of at least 9.5:1 or more.

想想一pulsejet具有压缩比约2:1或更少（CR）的-而你的车可能有至少9.5:1或高铬。

Now since the air-fuel mixture in your car doesn't detonate (except under exceptional circumstances) -- what chance do we have of getting a pulsejet to produce detonations?

现在，因为空气中的汽车燃料混合物不会引爆（除非在特殊情况下） -我们什么机会得到一个pulsejet的生产引爆呢？

[size=+1]So How do They do it?

[size=+1]所以 ， [size=+1]他们怎么做呢？

The exact details on many of the PDE designs currently being developed are rather sketchy -- mainly because they have the potential to be extremely valuable so most of companies researching in this field are not about to tell us what they're doing.

关于偏微分方程许多设计目前正在开发的具体细节则比较简略-主要是因为他们有可能是非常有益的，以便在这个领域研究的公司大部分都没有告诉我们他们在做什么。

However, from the information that has been published, it appears as if most designs are using a two-stage ignition process to achieve detonation.

然而，从已公布的信息，它显示为大多数设计中，如果使用的是两个阶段的进程，以实现点火引爆。

Once a fresh air-fuel charge has been drawn into the pipe, a much smaller amount of a very volatile fuel (such as hydrogen) and an oxidizer (such as oxygen) are injected into a trigger chamber at the closed end of the pipe.

一旦新鲜空气，燃油附加费已被卷入管道，一个非常动荡的燃料（如氢气）和氧化剂少得多（如氧气）正进入一个触发室注射管道的封闭式。

This mixture is then ignited by an intensely powerful electrical discharge and made to detonate by forcing it through some carefully designed passages which create high levels of turbulence in the burning mixture.

这种混合物，然后引发了激烈的强大放电并引爆，迫使通过一些精心设计的段落会产生动荡中的高浓度混合燃烧它。

This tube is sometimes referred to as a DDT (Deflagration to Detonation Transition) tube and its job is to force the trigger charge to burn at a rate that creates a supersonic shockwave.

这条管子有时被称为滴滴涕（爆燃向爆轰）管，它的工作是为了迫使速度创造了超音速冲击波触发负责燃烧。

Once it detonates, the small charge in the trigger chamber creates a very powerful shockwave that then hits the main air/fuel charge in the engine's secondary combustion chamber.

一旦引爆，触发器中的小室负责创建一个非常强大的冲击波，然后点击其主要的空气/燃料发动机二次燃烧室负责。

It may sound odd that it is possible to compress the gas in a tube which has an open end -- but the incredible speed of the detonation shockwave means that the air/fuel simply doesn't have a chance to be pushed out of the tube before it is compressed.

这听起来很奇怪，就可以压缩在一个管，结束了一个开放的气体-而是爆炸冲击波令人难以置信的速度意味着空气/燃料根本没有被赶出管出机会之前，压缩。

As, or because it is highly compressed, the air-fuel is also detonated by the intense heat of the shockwave.

正如，或因为它是高度压缩的空气和燃料，也引爆了冲击波酷暑。

Now while this all sounds pretty simple in theory, there are clearly quite a number of practical problems to be overcome before a working PDE can be built.

现在，虽然这一切听起来很简单，在理论上，明显有相当数量的实际问题之前，必须克服偏微分方程的工作，可建。

Firstly there's the issue of valving.

首先有问题的汽门。

The effective life of a traditional pulsejet tends to be measured in minutes rather than hours -- and that's even though they're only called on to handle the relatively low pressures generated by deflagration.

这是传统pulsejet有效寿命往往在几分钟内测量，而不是小时-而这，即使他们只是在处理相对较低爆燃产生的压力称为。

If you tried to use the same fragile valves when detonating an air/fuel mixture they would instantly be destroyed.

如果您尝试使用相同的脆弱的阀门时，引爆了空气/燃料混合物，他们将立即予以销毁。

To get around this problem, some of the existing PDE designs appear to use robust rotary valves -- but this often requires a sophisticated synchronization system to ensure that the externally driven valves open and close at exactly the right times.

为了解决这个问题，现有的偏微分方程的设计似乎有些使用强大的旋转阀-但这往往需要先进的同步系统，以确保外部驱动的阀门打开和关闭在正确的时间。

Another alternative is to use a valveless setup and rely on a careful synchronization of the shockwaves produced to control the gas flows.

另一种方法是使用无阀设置和依赖的生产控制气流冲击波仔细同步。

Other problems with PDEs at this stage of their development include being able to inject and detonate the trigger charge at exactly the right moment to produce detonation of the main air-fuel charge.

与偏微分方程的其他问题，这是他们的发展阶段，包括可以注入和引爆在正确的时刻触发爆炸负责生产的主要空气燃油附加费。

Too early and there won't be enough air/fuel to provide a good blast -- to late and the air/fuel will have already started leaving the tailpipe.

太早，也不会有足够的空气/燃料来提供一个良好的爆炸-后期，空气/燃料将已经开始离开排气管。

Then there is the problem of structural integrity.

然后是结构完整的问题。

What you're effectively doing with a PDE is repeatedly setting off a small charge of hi-explosive inside a metal tube.

你什么有效的偏微分方程做的是不断掀起一小负责高科技金属管内爆炸。

This obviously requires that a PDE be massively stronger than a pulsejet.

这显然需要一个偏微分方程的大规模比pulsejet强大。

It also means that the levels of noise and vibration are similarly far higher.

这也意味着，噪音和振动水平同样高得多。

One of the key players in the development of PDEs is NASA and they have a small but quite useful web page on the subject.

在偏微分方程的发展的主要参与者之一，是美国航天局和他们有一个小但很关于这个问题的有用的网页 。

CalTech have also published some excellent information on their own PDE research .

加州理工学院也纷纷发表自己的偏微分方程研究的一些优秀的信息。

[size=+1]The Current State Of Development

[size=+1]目前的发展状态

It seems that nobody yet has the PDE developed to the point of being a practical propulsion device (or at least if they have, they're not telling anyone).

似乎没有人尚未发展到一个实际的被推进设备点偏微分方程（或至少如果有，他们没有告诉任何人）。

From what I've been able to gather, the main focus is currently being placed on researching and improving the detonation process.

从我已经能够收集，主要重点是放在目前正在研究和改进的爆炸过程。

The current generation of PDEs don't seem capable of continuous running for any length of time -- they're more or less just single-shot devices requiring several seconds to recharge between detonations.

在偏微分方程目前这一代似乎不能够持续的任何时间的长短运行-它们或多或少只是单发设备需要几秒钟的时间充电之间爆炸。

[size=+1]Amateur PDE Development

[size=+1]业余磷酸二酯酶发展

Unfortunately pulse detonation engines are probably not the sort of thing that is well suited to amateur development.

不幸的脉冲爆震发动机很可能不是有一点是非常适合业余的发展排序。

The risks of containment failure (ie: a catastrophic explosion that turns your engine into a grenade) and the difficulties involved in obtaining reliable detonation of readily available fuels make both dangerous and likely to be quite disappointing.

遏制失败的风险（即：一个灾难性的爆炸，变成一个手榴弹你的引擎）和获取现成的燃料的可靠起爆所涉及的困难，使既危险，并可能会令人失望。

The sad truth is that you're unlikely to be able to coerce a mixture of gasoline and air or propane and air into true detonation using something you've built in your garage -- and if you do, the paramedics will likely have to take you away in a plastic garbage bag (that's if they can find all the pieces ;-).

可悲的事实是，你不大可能迫使真正使用的东西你在你的车库里建立引爆汽油和空气或丙烷和空气的混合物-如果你这么做，医护人员可能将不得不采取你带走的塑料垃圾袋（也就是如果能找到所有的作品;-)。

[size=+1]The Future of PDEs

[size=+1]未来的偏微分方程

Many developers have high hopes that the PDE will ultimately become the most cost-effective method of propelling supersonic sub-orbital craft.

许多开发人员具有很高的希望，PDE将最终成为最具成本效益的推动超音速亚轨道飞行器的有效方法。

The ultra-high compressions obtained by detonation offer the potential for much better fuel-efficiency than even the best turbojet, and the fact that they are an air-breathing engine reduces the fuel-load and increases safety when compared to rocket motors.

超由引爆提供燃油的潜力更好的效率甚至比最好的涡轮喷气发动机获得高压缩，而事实上，它们是吸气式引擎降低了燃料，增加安全负载相比，火箭发动机。

Unfortunately there are still a number of negative issues that will need to be addressed.

不幸的是仍然有一些负面问题需要加以解决。

Firstly there's the noise -- if you think regular pulsejets are loud then you'll be absolutely blown-away by the noise levels created by a PDE.

首先有噪音-如果你认为经常pulsejets是大声那么你是绝对吹，掉了一个偏微分方程的噪声创建水平。

Then there's the issue of vibration.

然后有振动的问题。

Although multiple engines could possibly be synchronized to fire in a manner that reduces vibration levels, they will still be significantly greater than those generated by turbojet or rocket motors. High levels of vibration place incredible demands on the materials from which motors and airframes are constructed.

从它的发动机和机身的构造材料，虽然多引擎也可能会被同步到火灾的方式，降低振动水平，但仍将大大高于由涡喷发动机或火箭发动机产生的。振动发生令人难以置信的高层次需求。