TY - JOUR TI - Research on average heat transfer control technology of passive ultra-low energy assembly building exterior wall AU - Wang Keqing JN - Thermal Science PY - 2025 VL - 29 IS - 2 SP - 1179 EP - 1195 PT - Article AB - This research focuses on passive ultra-low energy prefabricated buildings, aiming to reduce the external wall's heat transfer coefficient and enhance thermal insulation for energy conservation. The study calculates the average heat transfer coefficient of the external wall and surrounding thermal bridges, establishing an objective function for heat transfer control. By solving this function, optimal control parameters are derived. Experimental results demonstrate that this approach effectively improves insulation, maintains comfortable indoor temperatures, and significantly reduces energy consumption of the building's external wall. The experimental results show that the maximum difference between the calculated value and the actual value of the external wall heat transfer coefficient under the proposed method is only 0.02, the limit value of the average heat transfer coefficient is controlled around 2.0, the indoor insulation rate is up to 90.3%, and the energy consumption of the external wall is effectively reduced from 100-145 kJ with little fluctuation. Effectively improve the building insulation performance, ensure the indoor temperature stability, reduce energy consumption.