Building Form Generation Methods Based On Solar Irradiation

Solar irradiation is one of the most important factors that influence the architecture thermal environment. A series of complex heat exchange activities on the facades are all based on the initial solar irradiation received by the building form, which is quite significant for the establishment of thermal comfort in buildings.Building form design considering the usage of solar irradiation always has two aspects:use and defense. In cold areas the building forms trend to gain more solar energy to reduce heating load while the hot climate zone may prefer more shadings to reduce cooling load. In hot summer and cold winter regions the strategy for climatic adaptability may be more complicated. It is close to impossible to reach an objective and efficient form result with the trial-and-error approach alone, which is exactly the traditional design method. Thus we introduce the concept of "Performance Driven Architecture Generation System", which integrating the energy simulations during the conceptual design period and use a generation-optimization design method to find the best building form considering passive solar design strategies.This paper first describes several related cases and introduces three new methods to generate building forms:Twist, Plus and Minus, which can improve the thermal comfort in buildings. After that by using the Grasshopper, a visual programming parametric design software to establish the parametric model and introducing DIVA to analysis the corresponding solar irradiation level, Galapagos and Octopus then may gain the optimization results of three site-specific generation experiments.This study aims to develop a methodology with which architects can generate building forms for site-specific optimization target by integrating advanced simulation and optimization algorithm. As a result the building form in response to the site-specific environment conditions, may be useful and applicable for daily work of architects.