Research On Heat-insulating Design Principle And Inheritance Of Huizhou Traditional Dwellings

On account of the rapid development of new-type urbanization construction and close communication between Chinese and western architecture culture,traditional dwellings and the knowledge about its construction practices has fallen into oblivion,causing energy consumption growth of the rural building and modern dwellings construction without local characteristics.The objectives of this thesis is to research the forming reasons of indoor thermal environment in summer and extract heat-insulating design strategies suitable for modern houses based on the methods of extensive field study,theoretical analysis and energy simulation.Firstly,climate suitability design strategies of Huizhou traditional dwellings in summer were summarized through field investigation.It was found that heat-insulating design ideas and elements of dwellings can be seen from the spatial characteristics of the residential settlements and the style of the buildings.Furthermore,thermal environment measurements were conducted in typical dwellings to evaluate the effects of building designs on thermal environment in buildings.It was found that shading and buffer space reduced daytime heat gain and natural ventilation improved the heat dissipation capacity at night,which made indoor thermal environment comfortable and met 80% acceptable temperature range.Lack of natural lighting was identified as one of main problems that should be solved in traditional dwellings especially in wing-rooms because of the sealed envelope.Secondly,dynamic thermal balance models for whole and part of the dwelling were established respectively to determine the different capabilities of heat-insulating design contribution to the whole dwelling in summer.It was found that heat transfer quantity of roof is 69.2%,which more than other parts of the dwelling and should be addressed in the process of design.Different heat-insulating elements have different contribution to the dwelling heat protection,of which the greatest contribution rate is roof reflection,followed by reflection and shading effect of exterior walls and the lowest is long-wave radiation of roof and exterior walls.In the third part of this thesis,dynamic and static response models were established to analyze the response regularity of thermal environment between indoor and outdoor space.In air conditioning room,the indoor thermal environment is influenced by the parameters such as solar radiation reflectance,external shading coefficient,heat transfer coefficient,outdoor wind speed,solar radiation intensity,outdoor air temperature and indoor air temperature.In particular,the inner surface temperature of envelope were in inverse proportion to the external wall reflection coefficient and outdoor wind speed,and in direct proportion to the other design.Due to the existence of natural ventilation in courtyard,the indoor environment does not overheat even if high heat capacity materials are used in the envelope structure.Lastly,heat-insulating design technology,such as natural ventilation,indoor cold source,buffer space and sealed envelope design of Huizhou traditional dwelling,can be inherited in modern buildings.Optimizations were made for design strategies such as the materials and structure of building envelope and shading of external window in traditional dwelling.Numerical analysis was conducted to quantify the energy consumption and comfort performance of those design strategies.It was found that the effect of optimization merely in external wall was weaker than that merely in roof and the comfortable time in summer and winter could increase by 21% and 15% respectively,after simultaneously optimizing of roof and external wall.The shading of dooryard,south window and west window were important features in buildings.