The Structural Optimization Of The Exterior Walls Of High-rise Buildings In The Mode Of Natural Ventilation

The emergence of high-rise buildings can meet the living requirement better, but the followed energy consumption should not be overlooked. In China, with the progress of urbanization, large crowds will pour into cities. High-rise buildings will certainly have great prospects for development. With the high-rise building in the proportion of the total increasing, energy-saving of high-rise buildings is imperative. In this paper, it researches high-rise buildings using the ventilation cooling at night to create a comfortable indoor thermal environment in summer in Xi'an. And in the daytime high-rise buildings mainly rely on themselves to resistant temperature change, so the structure of building envelope directly relates to the level of building energy consumption. So the research priorities of this article will focus on the exterior walls.In this paper, we firstly describe the heat transfer process of the exterior walls during period of night ventilation and daytime, set out the corresponding thermal differential equations, and use the initial conditions and boundary conditions to get thermal differential equation of the corresponding temperature distribution in the exterior walls. For the insulation performance test of building's exterior walls ,we calculate the maximum temperature of the inner surface of the exterior walls in periodic harmonic heat during the daytime and compare it to the average temperature of the skin to determine which meets the demand of the structure.Through the comparison, the maximum inner surface temperature of several common structure of the exterior walls selected in the paper all meet demand. The multiples of decay of concrete walls which used polystyrene board insulation in the outer surface is better than that used polystyrene board insulation in the inner surface of the wall, which is about 5.88 times of the latter. It shows that concrete walls which used polystyrene board insulation in the outer surface can greatly decay harmonic outdoor hot role to ensure the indoor temperature to fluctuate smaller. For the non-load-bearing walls, multiples of decay of aerated concrete block walls which use polystyrene board insulation is 2.06 times of hollow brick walls, which can ensure the indoor temperature to fluctuate smaller. At the same time as a lightweight material, aerated concrete block can relieve themselves and meet high-rise buildings' requirements.Finally, we also discuss the problems existed in the construction of the exterior walls' insulation and give the appropriate recommendations.