Transcript · English → Chinese
English → Chinese transcript
如果我们能控制闪电，让它像牵线木 偶一样在空中弯曲呢？
今天我要向你展示一个听起来不可 能的突破。
我要用超声波引导电等离子体。
我可以在这两个换能器之间形成一 个驻波。
对于大于某一尺寸的固体颗粒，声辐 射力会把它们推向节点。
较小或更易压缩的颗粒则可能被推 向反节点。
所以你实际上可以像这样使颗粒悬 浮。
如果我有一块热空气，其密度和声阻 抗低于周围空气，
那么声辐射力会把那块热空气推向 反节点。
每当产生火花时，会释放出大量热量 。
我有一圈超声换能器，中心正好是一 个很强的腹点。
这意味着如果环中心有任何热空气， 它会被沿着那个腹点强行向上推。
现在我们离能把等离子体引导到想 要的位置更近了。
热空气会降低击穿电压，这意味着比 在冷空气中更容易形成电火花。
你可以看到，如果我用热风枪在两根 高压电极之间吹，火花就会产生。
这正是所需的热空气。
但如果我不把热空气吹到那里，火花 就无法形成。
所以如果我拿一台断续放电的特斯 拉线圈，前几次脉冲会产生一些热空气。
随后这些热空气会被引导到换能器 环的中心。
这就为接下来的火花提供了一条可 循的路径。
所以你得到的是来自特斯拉线圈的 一条漂亮受控等离子体直线，而不是一团混乱的火花。
我以大约每秒2000次的频率对特斯拉 线圈的输出进行脉冲，产生快速的火花序列来加热空气。
你可以看到它如何形成一个有序的 等离子通道，给出一条我能指向任意方向的整齐直线。
看那。
这太酷了，因为它有大量的应用。
如果你改变超声换能器的位置，就能 改变等离子体的去向。
你甚至可以让火花绕过障碍物。
或者你可以让它在你想要的确切位 置完成电路接通。
你甚至可以在不同位置产生触觉感 受。
这有许多很酷的应用。
真令人惊讶，我们竟然能仅凭声音就 引导等离子体。
我要感谢 Upna Labs 专门为我制作了这枚超声波戒指。
他们就研究发现及其潜在应用写了 一篇很棒的论文。
我会在视频描述中放上他们论文的 链接。
感谢观看。
End of transcript · 468 words · machine translated
Original transcript (English)
What if we could control lightning, bending it through the air like a puppet on a string? Today I'm going to show you a breakthrough that sounds impossible. I'm going to guide electric plasma using ultrasonic waves. I can create a standing sound wave in between these two transducers. For solid particles larger than a certain size, the acoustic radiation force pushes them into the nodes.
Smaller or more compressible particles might be pushed to the antinodes instead. So you can actually levitate particles like this. If I have a region of hot air which is lower in density and acoustic impedance than the surrounding air, then the acoustic radiation force will push that hot air toward the antinodes. Whenever a spark happens, an enormous amount of heat is generated.
So I have a ring of ultrasonic transducers so that right at the center is a strong antinode. This means that if I have any hot air near the center of the ring, it'll be forced right up that antinode. Now we're getting closer to being able to guide our plasma where we want it. Hot air lowers the breakdown voltage, meaning it's easier for a spark to form than in cold air. You can see if I blow my heat gun between two high voltage electrodes, a spark can form.
It's just the hot air needed. But if I don't put the hot air there, then it can't form. So if I take a Tesla coil that's pulsing on and off, then the first few pulses will make some hot air. And then after that, the hot air will be directed to the center of the rings. Now this creates a path for the next sparks to follow.
So what you get is a beautiful guided straight line of plasma coming from the Tesla coil instead of a chaotic mess of sparks. I'm pulsing the Tesla coil's output around 2,000 times per second to create a rapid sequence of sparks that build up hot air. You can see how it makes a nice ordered plasma channel that gives a nice straight line directed wherever I want. Look at that. This is so cool because it has a ton of applications.
If you change your ultrasonic transducer location, you can change where the plasma goes. You can even get the spark to go around obstacles. Or you can get it to complete circuits exactly where you want. You can even produce tactile sensations in different spots. This has so many cool applications.
It's so amazing that we can actually guide plasma with sound alone. And I want to thank Upna Labs for actually making this ultrasonic ring for me. They've written a great paper on their findings and potential applications. I'll put a link to their paper in the description. Thank you for watching.
