The Energy-saving Design Analysis Of Fixed External Blind Shading On East-west Orientation Residential Building In Guangzhou District

Shading is an important mean to improve building indoor thermal environment,it is uesful to help improve the quality of indoor environment and building energy efficiency. The main function of shading is to reduce the solar radiation that transmit into the buildings,but the exterior shading will also have an impact on natural ventilation. Although studies have been made by many scholars,but comprehensive studies for external shading are insufficient,Can not directly guide architectural design practice.East-west orientation of Building is the critical boundary that will absorb huge solar radiation,but the researches and applications about external shading on east-west oritation residential buildings are insufficient. Fixed external shading blinds are lightweight, transparent, delicate, will not lead to great adverse effects on the building’s natural ventilation while reducing solar radiation,always made by aluminum,which can be recycled. Fixed external shading blinds′s shading effect is remarkable and have a strong adaptation. because blind angle is fixed, so this shading system has a high safety and durability, and lower maintenance costs. As an "appropriate technology" can be well adapted to our country’s development needs.Guangzhou is the typical city of Hot Summer and Warm Winter Zone, residential buildings in Guangzhou have highly requirements on shading and ventilation. The recent implementation of <Design standard for energy efficiency of residential buildings in hot summer and warm winter zone >mandatory stipulated that east-west oritation windows of residential buildings in hot summer and warm winter zone must have external shadings, so it is necessary to explore the exterior shading means that adapt for residential building in Guangzhou.This paper make the east-west oritation residential building in Guangzhou as the research object, the main research work is as follows:1.Investigated froms of east-west oritation residential buildings in Guangzhou and surveyed the shading status of existing residential buildings, established the architectural model for the numerical simulation study.2.Using orthogonal test and Energy Plus computer simulation to analyse the sensitivity between the blind design factors and outside shading coefficient of window,determine the sensitive relationship between the blinds design factors and outside shading coefficient of window,get a regression equation used for fast predict the fixed external blind shading`s outside shading coefficient of window.3.Using computational fluid dynamics software FLUENT to research the pressure distribution of the architectural model which determined in step 1, and further research the effects of fixed horizontal external shading blinds on the wind pressure of building`s opening surface,get the pressure coefficients of the target surfaces used as a building energy simulation boundary conditions.4.Using energy simulation software Energy Plus and pressure coefficients obtained in Step 3 simulate the monthly cooling load of the architectural model established in step 1 under four conditions,respectively are no shading and no natural ventilation, shading without natural ventilation,shading with constant natural ventilation, shading with temperature-control natural ventilation. summarized the energysaving efficiency and application methods of fixed horizontal blind external shading on residential building in Guangzhou.