Ultra-thin Vacuum Insulation Materials-in The Field Of Home Appliances Applications
In recent years, vacuum insulation materials began to emerge in the field of home appliances. For example, a Japanese-made refrigerator with vacuum insulation material, the refrigerator wall thickness of only 2.8cm, only half of the normal refrigerator. This not only reduces the weight of the refrigerator but also increases the volume by 20% while selling prices have also increased by 25%. It can be said that the home insulation materials have ushered in the era of vacuum insulation.
1. The characteristics of vacuum insulation panels
Through the study, in the porous and fibrous insulation materials, the thermal conductivity is composed of four parts: λ = λ solid conduction + λ gas conduction + λ radiation + λ convection, and air conduction account for the material total thermal conductivity of 50%, or even Reached 80%. Therefore, a more efficient thermal insulation index can be achieved by reducing or even eliminating the dominant gas conduction, whereby the vacuum insulation panel is invented.
Vacuum insulation panels is a kind of material that adopts a series of effective optimization measures to minimize the gas and solid heat conduction of products with excellent thermal insulation properties. Vacuum insulation panels mainly include the external barrier material, the internal core material and adsorbent three parts. Vacuum insulation panels and other traditional insulation materials are significantly different, in the strict sense, it is not just a piece of insulation material, but a miniature vacuum insulation system. The performance of the miniature vacuum insulation system is good or bad, the length of life depends on the core material, barrier material, getter or adsorbent three options.
The role of the core material is to support the vacuum insulation panels, but also play a role in blocking the direct collision of molecules in the air for heat exchange. At present, a variety of core materials of vacuum insulation panels, different core materials will affect the initial thermal conductivity of vacuum insulation panels, life expectancy, so choose a good core material is the key. After years of production, the study found that glass fiber can be used as the core material of a vacuum insulation panel, and the finer the fiber, the lower the thermal conductivity.
The selection of barrier materials plays a key role in the life of the vacuum insulation panels. In terms of barrier properties, the barrier properties of aluminum are widely recognized, and most of the vacuum insulation panels use aluminum foil-containing barrier films. Currently widely used Aluminum composite film.
Through five years of follow-up observation, we found that placing a getter or adsorbent in a vacuum insulation panel will effectively improve product performance. Five years ago, the production of vacuum insulation panels placed without getter for comparison, the difference between the thermal conductivity nearly doubled.
The reason why the getter or adsorbent must be used is due to the core material bleed and the barrier film to leak gas. Slow release of residual gas from the core material in the vacuum insulation panel and slow infiltration of external gas into the interior of the vacuum insulation panel reduce the degree of vacuum and result in decreased performance.
2. The application of vacuum insulation panels
Vacuum insulation panels as a new type of environmentally friendly and efficient insulation materials, can be widely used in most areas of low temperature insulation. In the appliance can be used in the production of refrigerators, freezers, rice cookers, water heaters, display cabinets and so on.
Application to the field of vacuum insulation panel in the refrigerator as an example, the basic principle and basic configuration of the refrigerator cooling, there are several basic ways refrigerator energy, the main means for the introduction of energy-saving performance of the inverter compressor and better insulation material . In contrast, the use of thermal insulation material to achieve the effect of energy saving is relatively simple and easy, the effect is obvious.
Of course, the use of vacuum insulation panels also have a great relationship with the design. In the selection of a vacuum insulation panel, it is recommended to try to use a large-sized vacuum insulation panel, through theoretical analysis and practical application, practical applications generally use a large area of the vacuum insulation panel is better, and the smaller the area of the vacuum insulation panel, separated The worse the thermal insulation effect.
Research institutions of vacuum insulation panels have been studied in the case of household refrigerators, freezers placement and coverage, results show that the energy saving effect is closely related to the use and design of vacuum insulation panels will still be better in order to play through the whole verification Effect.
3. The future of vacuum insulation panels
With the development of vacuum insulation panel technology, the product's performance, price, cost-effective to meet the needs of more customers, the overall cost-effective than traditional insulation materials.
Thermal conductivity is an indicator of thermal insulation material properties, the smaller the thermal conductivity, the better the insulation properties of the material. Early high thermal conductivity of the vacuum insulation panel, the vacuum insulation panel with the development of technology, the current thermal conductivity of vacuum insulation panels has been gradually made 6mW / mK (20 ℃ test conditions) reduced to 3.5mW / mK (20 ℃ test conditions ), And can be stable batch production. It is believed that in the near future, the thermal conductivity of batch vacuum insulated panels can be lowered to 2 mW / m.K (20 ℃ test condition) or even 1mW / m.K (20 ℃ test condition).
The research shows that if the thermal conductivity of the vacuum insulation panel drops to 2.5mW / m.K in the future, the comprehensive cost will be about the same as that of the polyurethane material when the price per square meter drops to 100yuan, so that it can be widely used in the field of home appliances. With the continuous development of vacuum insulation panel technology and material science and technology continue to develop forward, in the near future, manufacturers will create a variety of shaped vacuum insulation panels outside the vacuum insulation panels, such as: round, Cylindrical, curved, perforated, vacuum insulated panels with grooves. This will greatly promote the use of vacuum insulation panels in more areas.