Abstract:The integrated performance simulation and genetic algorithm were adopted to optimize the design of office buildings in Xi’an, aiming at solving the problems of performance evaluation and dislocation of form design as well as the difficulty in weighing the negative correlation performance goal. Performance simulation was used to achieve the unification of architectural design elements and building performance, and genetic algorithms were applied to optimize multi-variable and multi-objectives to provide data support for program decision making. The performance optimization design framework for office buildings was established according to the logic of design, simulation, evaluation, and optimization. The performance optimization design applied to each link was formulated. Taking orientation, surface width, window-wall ratio, shading method, louver width, and louver inclination angle as variables, the individual buildings, surfaces, and details were optimized. A genetic algorithm was adopted to realize the optimization of building shape so as to improve energy consumption and light performance. A case study of an office building in Xi’an show that based on the climate characteristic quantitative energy-saving strategy, the utilization rate of passive solar energy was the highest. Taking the solar radiation gain of buildings as the target, the shape optimization result was that the long axis of the office building was in the northg-south direction and the length-width ratio was 1∶4. In the design of building surfaces, the window-wall ratios in different directions were taken as variables, the window-wall ratio in the south direction was 60%, and those in other directions were 40%. The time, light, and heat performance were excellent, so the external sunshade louvers were further optimized. Optimization results show that on the basis of the optimization of building surfaces, the total energy consumption was reduced by 3%, and the annual light exposure was reduced by 36.5%, while the percentage of all-natural lighting time in the space was not significantly decreased.
