Glass curtain wall thermal insulation

The thermal insulation performance of glass curtain wall is poor, and the ventilation effect is not good, which directly affects the equipment configuration and energy consumption of buildings, contrary to the national conditions of Our country. Thermal insulation performance refers to the heat transfer ability of curtain wall impedance from high temperature side to low temperature side under the condition of air temperature difference on both sides of curtain wall, excluding the heat transfer of air permeating through cracks. Curtain wall thermal insulation performance is expressed by heat transfer coefficient K.

The thermal insulation performance of curtain wall should be solved by controlling the total thermal resistance value and selecting corresponding materials. In order to reduce heat loss, the following three aspects can be improved: the first is to improve the thermal insulation performance of daylighting curtain glass window, as far as possible to choose hollow glass, and reduce the opening fan; The second is the non-lighting part of the use of good insulation effect of material after the lining wall or set up temperature core material; The third is to do airtight treatment and reduce ventilation.
Different climatic conditions in different places have different requirements for the performance of curtain wall. In hot summer and warm winter area, heat insulation is the main problem of building envelope energy saving. The thermal insulation performance of glass curtain wall is mainly for radiation, conduction and convection. When talking about reflective glass, people tend to emphasize only its radiation properties. Of course, radiation is the most important part of the above various ways, which can account for about 2/3 of the total heat, the main load of air conditioning also comes from solar radiation, therefore, it should effectively block solar radiation.
But in the actual use, such as aluminium curtain wall in lasting exposure, reflecting glass due to heat dissipation slower than other glass, although its reflection capacity is large, the accumulation of heat makes it inevitable to become a new heat source, so, glass curtain wall transmission capacity of solar energy is worth paying attention to the problem.
In the thermal design of curtain wall, it must be analyzed and studied in detail, such as the convection heat transfer between the exterior surface of the curtain wall and the surrounding air and the external environment, the heat transfer between the interior surface of the curtain wall and the indoor air&environment, the heat transfer between the modern curtain wall and the metal frame lattice, the radiation heat transfer reduced by the glass coating layer, etc.