Numerical Simulation Of The Bioclimatic Design Strategies In Historic Settlements In Chinese Hot-humid Regions

Facing to the deepening world energy crisis and environmental crisis, how to respond to the changing climate and do one’s best to correct the the bad behavioral model in current architectural activities is a great subject in front of modern architects and planners.Historic settlements in China seek the harmony between buildings and natural environment based on the principle of letting nature take its course. As they were created on the most basic nature law, they embody a kind of sustainable environmental consciousness. Comparing this with modern people creating a livable environment with mechanical means, the traditional planning and design concepts of many historic settlements are more adaptable to the changes of natural environment under conditions involving low energy consumption and environmental protection. Therefore, the research findings on the sustainable planning and design experiences of historic settlements will have essential practical significance, enabling to create modern bioclimatic human environments.In this paper, the bioclimatic design strategies of the historic settlements in Chinese hot-humid regions are investigated and analynized from the view of the modern bioclimatic architecture theory. As illustrative case studies, the thermal environment within the Shang-Gan-Tang village in Hunan and the Jin-Jiang-Li village in Guangdong and Ju-Bao-Jie traditional residence complex in Fujian, has been investigated quantitatively, through the use of computational fluid dynamics (CFD), to evaluate the interactions between settlement selection, layout, green design, building design, water system design and ambient environment, and verify the effect of those traditional bioclimatic design strategies.The passive cooling techniques of these historic settlements are summarized comprehensively for guiding the creation of sustainable modern human settlement suitable for people living for hundreds of vears.On the basis of this study, the author applied and got a research project named "Simulation of the original and authentic environment of historic village in hot-humid areas and research on its protection and renovation strategy" funded by NSFC (51208511) in2012. The innovative points of the study are as follow:Firstly, the thermal environment of a "passive cooling alley" is simulated numerically by using3-dimensional unsteady simulation method rather than steady simulaton method to reveal the whole dynamic passive cooling process of the alley. The results will promote the modern use of this passive cooling technique. In the meantime, a3-dimensional unsteady simulation model suitable for the climatic design of historic villages in Hot-humid regions is created.Secondly, a method for simulating the actual and complex environment instead of the "ideal" and simplified environment of historic settlements is created. It is a new and effective method to study the historic built environment and good for exploring and summarizing the sustainable design and planning experiences of historic settlements.Thirdly, porous media model is used in the simulation of thermal environment to improve calculation speed and effectively solve the problem caused by huge calculating capacity.In short, the main achivement of this study is to use CFD techniques to analyze quantitatively, not qualitively, the coincident relationship between natural environment and the site selection, the layout, the building design of historic settlements. The research results of the study confirm that CFD is a brand-new and very effective method for studying historic building and the historic built environment.