"The More You Wear, The Warmer You Get" Is Actually A Mistake

Under the influence of a wave of cold air, the temperature in Hangzhou began to drop to freezing point. Recently, a "sandwich dressing method" has become popular among young people, and is even more popular among young people.

What is "sandwich dressing"? Is there any scientific basis for this dressing method? The reporter interviewed relevant experts.

"The more you wear, the warmer you get"

Actually, it's a mistake

When it comes to warm clothing, "air layer" is a frequently mentioned word. Gu Bingfei, the dean and associate professor of the Fashion Design and Engineering Department of the College of Fashion Design, Zhejiang University of Technology, explained that no matter what kind of clothing, it can not be completely fitted. Therefore, the space between the human body and clothing is the air layer. As the human body continues to dissipate heat, it will slowly heat the air, and then the air will play the role of a warm layer.

When there are more pieces of clothes, there will be new gaps between each piece, and the new gaps can hold air - eventually creating a very thick air layer. When clothes are worn too much and the air layer is too thick, there will be obvious temperature difference from inside to outside, which will lead to "thermal convection" of air flow. Once "thermal convection" occurs, the loss of heat will be faster.

In addition to the "thermal convection" caused by temperature difference, too many layers will also accelerate the air layer flow. Especially when walking outdoors, clothes rub and squeeze each other with body movements, which will accelerate the flow of air layer between clothes and accelerate heat loss. It can be seen that "the more you wear, the warmer" is a mistake.

"Sandwich dressing"

Inner layer selection is the key

The so-called "sandwich dressing method" refers to dressing by imitating the multi-level structure of sandwiches.

The key point is that the inner layer close to the skin should be made of moisture absorption and breathable materials, such as close fitting thermal underwear, quick drying clothes, yoga clothes, etc; The middle layer can wear clothes with good heat preservation performance, such as fleece, fleece, thin cashmere, down vest, etc; The main function of the external protective layer is to resist the cold air and wind and rain outside. It is suitable to choose a hard coat or professional outdoor equipment, such as down jacket, cotton padded jacket, and assault jacket.

Gu Bingfei said that "sandwich dressing method" is a hot word this year, but its basic logic is similar to the "26 ℃ dressing method" and "onion dressing method" advocated in previous years.

In Gu Bingfei's opinion, the key to keeping warm is to have a certain thickness and form a sufficient air layer. At the same time, for clothes close to the skin, try to choose materials that are warm and comfortable to touch when you start. It is partly for this reason that the "sandwich dressing method" uses fleece, fleece and other clothes as the middle layer.

"From the perspective of close fitting clothing, soft, pure cotton or wool underwear generally has good moisture absorption and sweat discharge function, which can effectively prevent moisture from accumulating in the clothing after the human body sweats, affecting the puffiness of the outer layer, and reducing the thermal insulation performance." Gu Bingfei said that, like a period of popular plush underwear in the past, the moisture absorption effect is relatively poor, and the clothing looks thick, However, its thermal performance may not be better than the current popular thin cotton underwear. (Reporter Huang Huixian)

(Source: Qianjiang Evening News)