臨近11月，全國(guó)多地迎來(lái)了降溫天氣，許多人已經(jīng)穿上了羽絨服。

此前，話題“為什么羽絨服里穿薄點(diǎn)才暖和”沖上了熱搜。

A trending topic explaining why "wearing fewer layers underneath your down jacket keeps you warmer" has sparked lively discussion online.

一些網(wǎng)友表示，親身試驗(yàn)，鑒定為真：

另一些有網(wǎng)友表示不相信：

也有網(wǎng)友表示關(guān)鍵羽絨服里得是真羽絨：

還有網(wǎng)友不禁發(fā)出疑問(wèn)：到底為什么羽絨服里穿薄點(diǎn)才暖和？是真的嗎？

其實(shí)，不少文章等都曾提到，“穿得越多越暖”是一個(gè)誤區(qū)。

穿衣保暖的關(guān)鍵在于有一定的厚度，并且有足夠的空氣層。

In fact, "the more layers you wear, the warmer you are" is actually a misconception. The key to staying warm lies not just in thickness, but also in maintaining adequate air flow between layers.

空氣層指的是衣服和人體之間含著空氣的間隙。由于人體不斷散熱，會(huì)把空氣慢慢加熱，此時(shí)，空氣便起到了保暖層的效果。

An air layer refers to the space between your body and clothing that traps air. As your body continuously releases heat, it warms this trapped air, which then acts as an insulating layer.

那么，是不是層數(shù)越多、衣服里存的空氣越多，整體的保暖性也就越強(qiáng)了呢？

其實(shí)，事情并不是這樣！

我們可以把人體想象成一個(gè)圓柱體，衣服件數(shù)越多時(shí)，件與件之間會(huì)出現(xiàn)新間隙，新間隙又能容納空氣——最終就會(huì)造出一個(gè)很厚重的空氣層。

圖源：丁香醫(yī)生

而當(dāng)空氣層太厚時(shí)，空氣層從內(nèi)至外就會(huì)產(chǎn)生比較明顯的溫差。這時(shí)，空氣將不再靜止而是會(huì)流動(dòng)起來(lái)，這就是“熱對(duì)流”。

一旦發(fā)生了“熱對(duì)流”，熱量的流失反而會(huì)更快。

Think of the human body as a cylinder. When you wear multiple layers, new gaps form between each piece of clothing, each capable of holding air — ultimately creating a very thick air layer. However, when this air layer becomes too thick, a significant temperature difference develops between its inner and outer parts. This causes the air to circulate rather than remain still — a phenomenon known as "thermal convection". Once thermal convection occurs, heat loss actually accelerates.

除了溫差導(dǎo)致“熱對(duì)流”，層數(shù)太多還會(huì)把空氣層擠薄。當(dāng)層數(shù)超過(guò)某個(gè)值后，衣服層與層之間的空氣存量，反而會(huì)隨著衣服層數(shù)的增加而減少。

特別是在戶外走動(dòng)時(shí)，衣服隨著身體動(dòng)作出現(xiàn)相互摩擦、擠壓，這會(huì)加速衣服間空氣層流動(dòng)，加劇熱量散失。

Besides triggering convection, too many layers can also compress the air spaces between them. Beyond a certain point, adding more layers actually reduces the amount of trapped air between garments. This effect is especially noticeable during outdoor activities, where body movement causes clothing to rub and compress against each other. This disrupts the air layers and speeds up heat loss.

反而，穿的件數(shù)少，空氣層會(huì)相對(duì)薄些，不易引發(fā)熱對(duì)流。并且人體散發(fā)的熱量也會(huì)充斥著整個(gè)衣下空間，內(nèi)部冷熱相對(duì)均勻一些，體感上更暖和。

On the contrary, wearing fewer layers results in a thinner, more stable air layer that is less prone to convection. Body heat can then evenly fill the entire space beneath the clothing, creating a more uniform and warmer microclimate.

根據(jù)這個(gè)原理，在寒冷的冬天，我們可以參考這個(gè)“三明治”穿搭公式：

圖源：丁香醫(yī)生

當(dāng)然，如果你的抗寒能力強(qiáng)，可以再減少中層，穿件加絨速干服或者長(zhǎng)袖T恤，外面套一件防風(fēng)羽絨服就足夠啦。

說(shuō)起羽絨服，大家知道各種冬季保暖裝備的英文表達(dá)嗎？快來(lái)一起學(xué)習(xí)吧。

羽絨服 down jacket

長(zhǎng)大衣 overcoat

防風(fēng)夾克 windbreaker

連帽衛(wèi)衣 hoodie

毛衣 sweater/jumper

開襟毛衣 cardigan

秋褲 long underwear/long johns

保暖內(nèi)衣 thermal underwear

耳套 earmuffs

連指手套 mitten

五指手套 glove

靴子 boots

編輯：李金昳

實(shí)習(xí)生：李然

來(lái)源：外研社UNIPUS 科普中國(guó)等

跟著China Daily

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