Application of vacuum glass in the hottest green b

The application of vacuum glass in green buildings

in modern architecture, whether living or working, people pursue diversification and fashion, and require spacious, bright, transparent and comfortable. Building forms are increasingly using large-area daylighting glass windows and glass curtain walls. However, due to the influence of environment and climate, indoor environment usually needs to consume more energy to be comfortable. How to solve the contradiction between building demand and building energy conservation? The key is technology. Only by developing and applying advanced energy-saving technologies and materials can we improve building quality, reduce building energy consumption and achieve the goal of green building

1 analysis of building energy conservation industry standards

enclosure structure is the key part of building energy conservation. Due to the poor thermal insulation performance of the building envelope, the energy consumption of heating in winter and air conditioning refrigeration in summer is high. A large area of public buildings with glass curtain walls for academician workstations established with academicians from Xigao have higher energy consumption. Therefore, the national and local standards on building energy efficiency have rigidly stipulated the area ratio of windows and walls in all directions, which is really a last resort to limit building energy consumption. The role of glass in modern architecture is very important and indispensable. The demand for energy-saving glass in modern buildings is becoming increasingly urgent

the thermal performance of the external window is 3 ~ 4 times worse than that of the external wall and roof, which makes the external window, which accounts for a small proportion of the total area of the building envelope, account for a high proportion of energy consumption. On the one hand, the reason for this phenomenon is the concept of energy conservation. The commonly used window frame profiles have poor thermal insulation performance, and the energy-saving effect of glass, which accounts for the absolute majority of the window area, is often ignored. Many high-end residences and even high-end villas only use double white insulating glass with poor thermal performance, which makes the thermal insulation performance of glass windows and walls far different; On the other hand, the thermal performance of the glass material, which accounts for the main area of the outer window, is poor and cannot reach the thermal level of the wall material, making the outer window a major short board of building energy conservation

the key to reducing the energy consumption of glass external windows (or glass curtain walls) is to improve the thermal performance of glass. Therefore, it is necessary to develop an energy-saving glass with excellent thermal insulation performance, so that the glass window system and glass curtain wall system composed of it have thermal performance comparable to the wall, so that the energy consumption of all parts of the building envelope is balanced, and the length of the cord should be appropriate to eliminate the short board

2 performance parameters of vacuum glass

vacuum glass is a new type of energy-saving glass. Based on the principle of thermos bottle, it seals two pieces of glass around, forming 0. 1～0。 2mm thin vacuum layer. Because there is no gas heat transfer, and there is a transparent low radiation film on the inner surface that acts as the silver film of the thermos, the thermal insulation performance of the vacuum glass is far better than the insulating glass that has been widely used at present. The heat transfer coefficient K of vacuum glass can be as low as 0. Below 6w/(M2? K), which is similar to the thermal performance of the insulation wall. At the same time of heat insulation, it also has the characteristics of sound insulation and noise reduction, anti condensation, and improving comfort

vacuum glass can be selected to be composed of glass with different thickness, different varieties or different functions. Therefore, vacuum glass has different heat transfer coefficients and shading coefficients to meet the thermal requirements of different climatic regions. Under the action of atmospheric pressure, the two pieces of glass constituting the vacuum glass are closely combined into a whole and cannot be cut, but they can be combined with other glasses by means of gluing or hollow closing, so as to form a composite vacuum glass to meet the needs of different projects such as doors, windows and curtain walls

3 vacuum glass improves energy-saving indicators

in 2006, China began to implement the "green building evaluation standard", which is why vacuum glass technology and products have been rapidly developed and widely used. The application of vacuum glass can significantly improve the following performance indicators of the building in the theme planning specified in the green building evaluation standard, and improve the quality of the building

3. 1 energy saving standard

(1) The thermal insulation performance of vacuum glass is close to that of the wall. Compared with ordinary hollow glass windows or Low-E hollow glass windows, the thermal insulation performance of vacuum glass windows has obvious advantages. According to the actual inspection of the national construction quality supervision and inspection center, vacuum glass windows can save more than 50% energy in winter when used in cold areas such as Beijing. Therefore, whether it is glass windows or glass curtain walls, the transparent enclosure structure is no longer the short board of building energy conservation, and the energy consumption of the whole building can be significantly reduced to meet the indicators specified for green buildings

(2) due to the needs of building functions, when the window wall area ratio exceeds the specification requirements and needs to be weighed and calculated, the thermal indicators of vacuum glass windows can meet the requirements of weighing and judgment

(3) for the needs of building appearance design, when a part of the enclosure structure cannot meet the requirements of the specification and needs to be weighed and judged, the thermal indicators of vacuum glass curtain wall can meet the requirements of weighing and judging

3。 2 indoor environmental quality

(1) noise: the weighted sound insulation of vacuum glass is more than 36dB, and that of composite vacuum glass is more than 40dB. Using vacuum glass windows or curtain walls can effectively isolate outdoor noise and improve indoor acoustic environment

(2) anti condensation: the super thermal insulation performance of vacuum glass can completely isolate the indoor and outdoor ambient temperature, and the anti condensation factor is> 75. Even in the cold winter of minus 20 ℃ outdoors, the temperature difference between the surface of the glass room and the indoor air will not exceed 5 ℃, which is much higher than the condensation temperature

(3) comfort: the super thermal insulation performance of vacuum glass is easy to maintain indoor constant temperature and humidity. The difference between the surface temperature of the glass room and the room temperature is less than 3 ~ 5 ℃, which eliminates serious cold and heat radiation, reduces the temperature gradient in front of the window, and significantly improves the indoor environmental comfort

the heat transfer coefficient and shading coefficient of vacuum glass can be designed and selected according to requirements. For buildings in different climatic regions, vacuum glass with different thermal performance can be selected according to the local building energy conservation requirements. In the cold regions of North China, attention should be paid to thermal insulation to minimize the loss of indoor heat; The hot summer and cold winter areas in the South should not only pay attention to heat preservation in winter, but also pay attention to the development of headquarters economic season heat insulation in summer to reduce the entry of solar radiation in summer. The thermal performance of vacuum glass should also be different for different lighting surfaces of the same building. Only by paying attention to details can we ensure the best energy-saving effect

global glass () Department