Study On Thermal Performance Of Prefabricated Multi-cavity Composite Wall

Energy issues have been enduring in the era of rapid economic and social development,and energy conservation and emission reduction has become one of the mainstream topics in today's society.For a long time,building energy consumption accounts for a quarter of total energy consumption in China.It is imperative to carry out energy conservation from the construction and it is of great significance.Building industrialization is an inevitable trend in the development of China's construction industry,and it is also an energy-saving reduction in China's construction industry.An important way of platooning.As one of the important external protective structures,the wall's heat loss accounts for 25% of the building's energy consumption.The thermal conductivity of air itself is much lower than that of common insulation materials.The use of air layer as the insulation layer of the envelope has a significant effect on energy consumption reduction.This paper combines the industrialized assembly house with the energy-saving of the external protective structure wall as the starting point,and studies the thermal performance of the composite wall containing the cavity.The research has theoretical significance and practicality for the development and promotion of the future assembly-type building.Engineering application value.This paper analyzes the existing assembly system and the advantages and disadvantages of each system through actual research,summarizes the insulation forms often used in each system and the insulation wall structure,and analyzes the application of multi-cavity composite wall in prefabricated buildings.Situation and prospects.The main factors affecting the multi-cavity composite wall are the thickness of the cavity,the wall material and thickness,the temperature difference between the two side walls of the cavity wall and whether the wall is ventilated.In order to study the influence of factors affecting multi-cavity composite wall on its thermal insulation performance,this paper uses the Fluent fluid calculation software to carry out qualitative and quantitative simulation analysis of multi-cavity composite wall by setting different cavity thickness and cavity.Different wall materials on both sides of the body,different wall temperature differences inside and outside the cavity,and the walls of different heights are simulated according to the common dimensions of the existing assembly houses.The optimal thickness of the cavity is 20 mm,and the wallis The influence of material and temperature difference on the thermal performance of the wall is significant,and the height variation of the wall has little effect on the thermal performance of the wall.Through the PKPM energy-saving calculation software,this paper compares the original composite thermal insulation wall and the multi-wall composite wall in the actual assembly project with energy-saving simulation.It is concluded that adding the cavity on the basis of the original thermal insulation wall can significantly improve its energy-saving effect.The proportion of the load is reduced by 2.21%,the load on the external wall is reduced by 2.93,and the thermal performance is obviously improved.In summary,this paper attempts to study the energy-saving effect of multi-cavity composite wall in prefabricated building from theoretical analysis,actual research,energy-saving simulation and comparison with actual engineering application simulation.It is expected that in the future,China will be able to save energy.Technical research provides a reference basis.