Climate Impact on Architectural Ornament Analyzing the Shadow of Khavoons in Dezful Historical Context with the Use of Image Processing

Due to increasing global pressure on the environment caused by human interventions, the studies on interaction of traditional building and their components with nature has been increased. These studies attempt to identify natural building design and determine how to use them in the climatic design of today's architectural design. Building performance simulation enables the examination of the effectiveness of innovative energy efficiency measures and control strategies. Daylighting is an effective approach to allow architectural design and construction practice to have a more flexible design of building facade, and to enhance a more energy-efficient and greener building development. Energy savings resulting from daylighting not only would mean low electric-lighting and reduced-peak electrical demands, but also it means reduced cooling loads and the potential for smaller heating, ventilating and air-conditioning. The absorbed solar radiation acts to raise the surface temperatures and consequently the temperature of the adjacent air layers. This has a significant effect on the generated thermal conditions, which is, in turn, reflected on the thermal behavior of the surrounding habitable spaces. In tropical areas, especially in warm humid areas, the need for shade and air ventilation are most important factors used for the provision of thermal comfort. In climatical and morphological studies of dezful historical context, great appliance of shade and ventilation can be seen. Among the hundreds of ways to do this, one of them is using khavoon (brick work) that creates shadow on the inner and outer walls and increase visual richness of the environment. This paper attempts to understand patterns of the brick khavoon in the way they were used; and to evaluate their shadows. These patterns became 3D using schetchup software and their shadow have been prepared at different hours of day and different directions. The amount of shadow has been calculated and analyzed by the image processing, IMAGEJ software. It seems that such patterns, in different orientation, increase amount of shadow (2.5 - 4.5 times). Given the size of the hourly solar radiation on the walls in each direction, the best direction of using this patterns can be identified.