Design and adaptability analysis of filling rate of a self-insulation wall considering thermal performance, benefit-cost, and cold-winter and hot-summer climate

The filling rate of different insulation materials significantly affects three influencing factors of self-insulating walls: insulation performance, benefit-cost, and climate adaptability. However, considering only one or two influencing factors of a self-insulating wall cannot satisfy the comprehensive needs of building users. Therefore, this experiment comprehensively considered three influencing factors to design five types of self-insulating wall models with different filling rates (0%, 25%, 50%, 75%, and 100%) to obtain the best filling rate scheme for insulation materials. EnergyPlus software was used to simulate the operating state of the self-insulating walls. A comparative analysis of the thermal performance and economic benefit indices indicated that compared to Type (A-1), the average inner surface temperatures of Types (B-1), (C-1), (D-1), and (E-1) increased by 1.49%, 2.72%, 3.56%, and 4.47%, respectively, indicating that an increase in the filling rate of the insulation materials improved the insulation performance of the self-insulation wall. With the same increase in the filling rate of 25%, the energy consumption of type (B-1) decreased by 8.66 KWh/m2, and the decrease range was the largest (i.e., by 7.65%), indicating that Type (B-1) offered the best value for money in terms of energy savings and material costs. The EPS filling rate of Type (B-1) is 25% and the thickness is 30 mm, which best meets the requirements of the economic thickness value of thermal insulation material (dEPS≥27 mm), which also indicating that Type (B-1) can satisfy the comprehensive requirements of thermal insulation performance and cost savings in hot-summer and cold-winter climates, so Type (B-1) is the best filling scheme.