Phase change thermal storage materials are a cutting-edge topic in the field of refrigeration technology in the world today, and also the development direction of China's current and future refrigeration industry. At present, various phase change cold storage materials have been successfully developed both domestically and internationally, such as expansion type, compression type, absorption type, etc. The development and application of these new materials provide humans with an efficient and environmentally friendly green air conditioning system.
Below, the Science and Technology Editor of the Advanced Institute will briefly introduce the academic introduction of phase change thermal storage materials.
1、 What is phase change energy storage?
1. Definition:
The principle of energy storage and supply is achieved by utilizing the physical changes of matter under certain temperature and pressure conditions to release or absorb energy, and by changing the form of matter to achieve energy storage and transmission.
2. Function:
Used for energy storage in low-temperature environments, it can effectively improve the stability of the power grid; Energy supply for high-temperature environments can meet cooling requirements while reducing grid operating costs; Used for industrial production process control, it can greatly improve the reliability of equipment operation; Used for building energy conservation, it can effectively reduce indoor heat loss and improve indoor air circulation; Used in the military field, it can be used for insulation of weapons and equipment, as well as human protection.
3. Characteristics:
(1) High density: Due to its porous structure, its specific volume can reach thousands of liters per cubic centimeter;
(2) Low thermal conductivity: Due to the porous structure, its thermal conductivity is only 0.0002w/mk, far lower than other types of insulation materials;
(3) Strong heat absorption ability: Due to the presence of porous structure, its heat absorption rate is very fast.
1. According to the state of matter: divided into two types: solid and liquid
2. According to usage, it can be divided into two types: direct use (i.e. evaporation type) and indirect use (i.e. compression type and absorption type)
3. According to working temperature: it can be divided into low temperature type and high temperature type
4. According to work pressure, it can be divided into three types: normal pressure type and pressure reducing type
3、 How to determine whether a product belongs to phase transition?
1. Observe the appearance of the product. If there is frost on the surface, it indicates the presence of liquid droplets inside; If bubbles are generated, it indicates that there is gas inside.
2. Touch: Touch with your hand. If it feels cold, it means the product contains liquid, otherwise it is solid.
4、 What is' dual carbon crystal '?
Dual carbon crystal is a composite plate composed of two single crystals, which not only has the high strength of carbon crystals, but also has the good insulation effect of alumina. At the same time, it also has the characteristics of metal, such as easy cutting, easy polishing, not easy to scratch, not easy to deform, high hardness, acid and alkali resistance, and not corrosive.
