Introduction to thermos

- Aug 22, 2019-

Thermos, also known as thermos bottles, daily necessities, shells made of bamboo, iron or plastic, with bottles inside. The bottle liner is made of double-layer glass, and the two sides of the interlayer are plated with silver and other metals, and the middle is evacuated into a vacuum, and the bottle mouth has a plug, which can maintain the temperature inside the bottle for a long time. Hot water is usually called a thermos bottle; cold food is usually called an ice bottle.

The inventor of the thermos: British chemist and physicist James Dewar (1892), hence the name Dewar.

The concept of a thermos is simple: the bottle has an inner wall and an outer wall; the walls are vacuumed. Thermal conduction and convection are not possible in a vacuum, and the plated metal reflective layer can reflect thermal radiation. Therefore, any liquid poured into the bottle can maintain its original temperature for a long period of time. This is why the thermos keeps the drinks warm in the winter and keeps the drinks cool in the summer. Many people who have participated in many trips find it difficult to imagine what it would be like without a thermos bottle.

Dewar produced liquid oxygen at a low temperature of minus 240 ° C. In order to preserve this liquid oxygen, he designed a bottle that could not be transferred and could not be released. The thermos we used evolved from this "Dewar". Dewar's thermos is designed according to heat transfer: 1 It is made of two layers of glass bottles, the middle of which is vacuumed to isolate the heat conduction and convection of the air; 2 the walls of the bottle are coated with silver, just like the mirror reflects light In that way, the heat radiation can be reflected back into the bottle; 3 bottles of cap stoppers prevent the heat from slipping out of the bottle mouth, and if used to fill the water, it becomes a thermos bottle.