Why can the insulation cup vacuum layer be insulated?What is the difference between products such as insulation cotton?

answer:

The physical principles have a different way to return. Both the vacuum layer and the thermal insulation cotton have a very low thermal conductivity.

There are three types of heat transfer mechanisms: heat conduction, heat -to -flow and heat radiation. Let's introduce a glass of water to introduce. When we hold a glass of water in winter, our hands can feel warm. This is the heat conduction; when we are close to the cup, our faces also feel warm, this is the natural convection of the heat in the air; We put a cup of cold water under the sun, and the sun was exposed to the heat of the sun.

Speaking back the topic:

A common vacuum heating layer, an important principle is to reduce the heat transmission caused by air by reducing the vacuum degree. Its thermal conductivity can be as low as 0.004 w/(m · k). In contrast K), you can obviously see its order gap.

The heat conduction coefficient of common insulation cotton shown below:

Picture Source | Reference Information

Therefore, both vacuum layers and thermal insulation cotton have extremely low thermal conductivity.

TIPS: The principle of the insulation cup is not just the vacuum layer. The vacuum layer effectively suppresses the heat convection and thermal conductivity. At the same time, the inner layer of the vacuum layer is also reflected back to the inside of the thermal inside through the method of plating the heat coating to achieve efficient thermal insulation.

Reference materials:

[1] Chen still. Research on the application of building insulation materials [J]. Sichuan building materials, 2022,48 (03): 8-9.

[2] Mao reward,, Ankang, Bai Yue, Lu Jiaxi. Internal vacuum on the heat conduction coefficient of vacuum thermal heating board [J]. Low temperature and superconducting, 2019,47 (03): 55-60+94.

by Justu

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