科学美国人60秒:Future Wet Suits Otter Be Warmer

Whales, seals and walruses stay warm in chilly water because they have a thick layer of blubber. We humans rely on something like blubber—neoprene rubber wet suits—to spend time in cold water. But the thick versions for really icy water are heavy and ungainly. So rather than taking after big marine mammals, what if we could learn from the littler ones,like beavers and otters?
鲸鱼，海豹和海象在寒冷的水中保可以持体温温暖是因为它们有很厚的一层鲸脂。我们人类也有类似的物质——合成橡胶材质的潜水服——可以在冰冷的水中活动时使用。可是在冰水中穿加厚版既沉重又笨拙。那么除了效仿大型海洋哺乳动物，如果学习一下体积较小的是不是也行呢，比如说河狸和水獭?

“These animals are quite small and they can't carry around a thick layer of blubber. So instead they have fur that is evolved to trap air, and this air provides a layer of insulation for them in water.”
这些动物体积较小而且不具备一层厚厚的鲸脂。所以，它们有进化出可以限制空气的毛代替那层鲸脂，而这种被限制住的空气就为它们在水中活动的时候提供一层隔绝热的保护层。

Alice Nasto is a graduate student in mechanical engineering at MIT. Scientists have known about this air-trapping insulation mechanism for a long time, but they had not teased out the details of how it works. So Nasto and her colleagues took on the challenge.
Alice Nasto， 是麻省理工学院机械工程专业的一名研究生。 科学家们很早就发现这种限制空气形成的绝热机制，但他们过去一直没有搞定这种机制起作用的具体细节。所以Nasto和她的同事们开始接受了这一难题。

“We're creating these furry samples from these rubbery materials by laser cutting molds and casting these hairy surfaces. And through our approach we can precisely control the spacing of the hairs [and] the length of the hairs.”
我们通过激光切割模具和铸造工艺用这些橡胶材料制造出了毛皮样本类似物。通过这种方法，我们可以精确的控制细丝间的距离以及细丝的长度。

The researchers then created a system to gather data when their pelts entered and moved through a liquid—in this case not water, but silicone oil, which makes it easier to see air bubbles. The key is to keep the pelt’s air layer intact.
研究人员们之后就制造出一个系统，用于在他们将这些样本急速送入一种液体和急速取出的时候收集相关数据——这种液体并不是水，而是硅油，用它可便于试验过程中看到空气泡。试验的关键是保持这种仿毛皮上的空气层完好无损的存在。

“So when they're crossing the air water interface, initially their hairy texture is full of air. And then you go into water. How much of the air comes down with you as you're moving in through the interface. So that's what this model will tell you.”
所以当它们穿过空气和水的接触面，开始时毛发材质充满了空气。然后，你把它们投入到水中。当你移动它穿过两种不同界面的时候，你随之可以带动多少的空气?所以这就是我们设计的这个模型能够为你搞清楚事情。

They found that the denser the hairs, the more the air gets trapped. Which should keep the animal—or potentially the human in a future furry wet suit—warm. The research is in the journal Physical Review Fluids.
他们发现，细丝的密度越大，被限制住的空气就越多。这就可以保持动物——或者未来也许是穿着仿毛皮潜水服的人类——体温，保暖。 该研究已发表在《流体的物理观察》杂志上。

“What we would like to work on moving forward is understanding how, after you dive into the water, how do you maintain this air layer trapped in your fur. And there's lots of interesting properties of the fur in nature that we haven't yet looked at in our model that could help explain how this mechanism might work.”
我们现在想要推进的工作就是了解一下，在你跳入水中后，如何能保持外面这些毛发能一直形成这种空气绝热层。而在我们设计的这个模型中，这种毛还有很多有趣的特点，我们并没有研究，进一步了解它们也许能够解释这种现象的作用机制。

So for now, cold-water divers and surfers will still emulate seals or sea lions. But the day may come when they’ll more closely resemble otters or beavers. Or even a Wookiee on a boogie board.
现在，冷水潜水或者冲浪者仍可以模仿海豹和海狮。而模仿水獭或者海狸的那一天，终将会到来的。或许可以看到一个在甲板上准备跳水的“伍基人”。