Study On Thermal Insulation Peculiarity And Energy Consumption Of Complex Phase Transition Insulation Wall In Extremally Hot And Cold Regions

Under the background of the incessant promotion of building energy conservation norm,based on the extreme thermal environment in Turpan and the strong demand for the heat insulation property of building enclosure,this study combines phase change materials(PCMs)with building walls,The heat transfer process of complex phase transition wall without heat insulation(complex phase transition wallⅠ)and complex phase transition wall with heat insulation(complex phase transition wallⅡ)under natural aeration and air conditioner conditions with different phase transition temperature,different ply of phase transition tier and different structure site is calculated;The influence of solar radiation direction difference,working conditions on the optimal phase transformation parameters and the influence of insulation layer on the phase transformation parameters of Turpan in summer are analyzed;The design parameters,such as phase change temperature and phase transition tier ply,which are most favorable for Turpan thermal insulation in summer under natural aeration and air conditioner conditions are determined;Furthermore,the heat-transfer properties,the heat charge and discharge properties of the optimized complex phase transition thermal insulation wall are explored;Finally,the energy depletion simulation application is used to analyze the effect of phase transition mortar site on the energy depletion of building air conditioner in summer.This study provides theoretical support for the application of phase change mortar in building insulation in Turpan.1.In this case of natural aeration condition and air conditioner condition,the best phase transition temperature of the complex phase transition wall facing the outside has a great influence,and the order of the best phase transition temperature from large to small is:South>East,West>north.The direction difference of the inner side composite phase change wallⅠis only reflected in the north;there is almost no difference in the direction of the inner side complex phase transition wallsⅡ.Secondly,the calculation shows that the existence of insulation tier has a great influence on the optimal phase transition temperature,which will increase the outer phase transition temperature and decrease the inner phase transition temperature.2.In different environments,choose the appropriate phase transition temperature,phase transition materials can fully carry out heat charge and discharge so as to achieve the best heat insulation effect.The best phase transition parameters suitable for the existing energy-saving buildings in Turpan are obtained.(1)The calculations show that the optimal phase transition temperature of the outer side phase transition wallⅡis the same under natural aeration and air conditioner conditions,and the first-rank phase change temperature of the four directions is 40℃,41℃,40℃and 37℃respectively.Under the natural aeration condition,the optimum phase transition temperature of the inner side phase transition wallⅡin four directions is35-36℃.The calculations show that the optimal phase transition temperature of the inner side phase change wallⅡis 26℃in the air conditioner condition.(2)The optimum ply of phase transition tier is the same under natural aeration and air conditioner condition.The first-rank ply of phase change tier in the four orientations of the outer side phase transition Wall II is 35mm,35mm,35mm and 25mm;The optimum ply of phase transition tier in the four directions of the inner side phase transition wallⅡis 25mm.3.Taking the west wall as an example,the heat-transfer properties and heat charge and discharge law of complex phase transition wallⅡunder the optimal phase transition parameters are analyzed.(1)Under the natural aeration condition,from the wall surface temperature,the outer side complex phase transition wall reduces the outdoor temperature peak by 10.2℃,and the inner side complex phase transition wall reduces the wall surface temperature by 3℃.In terms of attenuation ratio and delay time,both the outer and inner side complex phase transition walls have a certain degree of increase compared with the common control wall.In terms of the total amount of heat charge and discharge,the outer complex phase transition wall is 2.3times and 2.5times higher than the common control wall.In terms of indoor heat gain,the inner and outer complex phase transition walls are 18.8%and 35.6%lower than the common control walls.(2)In this case of air conditioner,the outer complex phase change wall can reduce the peak outdoor temperature by 10.3℃.In terms of total heat charge and discharge,the external complex phase transition wall is 3.29 times and 4.29 times larger than the ordinary control wall.The indoor heat gain of the inner and outer complex phase transition wall is 16.86 W/m~2 and 45.5 W/m~2 lower than that of the common control wall.The heat charge and discharge peculiarity of the inner and outer complex phase transition wall are better than that of the common control wall.The complex phase change wall can promote the capacity of the wall to resist the outdoor heat disturbance,strengthen the overall heat charge and discharge peculiarity,and realize the thermal requirements of the external envelop enclosure in Turpan.And the thermal peculiarity of the complex phase change wall outside is better.4.The energy depletion of three kinds of enclosure structures under air-conditioning conditions is analyzed and compared.The complex phase transition heat insulation wall can effectively reduce the energy depletion of building air-conditioner in summer.Compared with the common control building,the outer phase transition mortar and the inner phase transition mortar can reduce the energy depletion of air conditioner by 11.6%and 3.6%in summer.Therefore,from the perspective of energy saving,the energy saving strength of the outer complex phase transition heat insulation wall is better than that of the inner complex phase transition thermal insulation wall.