Application Study On Natural Ventilation Of Official Buildings In Shenzhen

Natural ventilation is a relatively economical ventilation method. As can bring large amounts of ventilation volume without energy consumption, natural ventilation is profit to environment protection which is widely utilized in industrial buildings and civil buildings. However, natural ventilation mature in residential buildings is still seldom used or Subject to a variety of factors in official buildings. From the survey on natural ventilation utilization of official buildings in Shenzhen, 68% of official buildings doesnot have any natural ventilation designs or doesnot have efficient ones, thus most dwellers feel uncomfortable or dissatifact about indoor air quality. They claim that it is essential to make use of natural ventilation in order to enhance indoor air quality and raise work efficiency.It is analyzed from the survey that there are 5 reasons for the utilization limit of natural ventilation in official buildings of Shenzhen. The reasons includes outdoor air quality and noise, the influence of air conditioning system operation mode, outdoor wind speed, building heat-gain and building form, and the vacancy of natural ventilation design. For the above reasons, in order to provide ventilation designers with accurate information, researches in 3 aspects is undertaked in this paper, namely, the research on urban wind environment, the analysis on the application effect of natural ventilation in a official building of Shenzhen, the discussion on the natural ventilation technology appropriate for official building of Shenzhen.The research on urban wind environment in Shenzhen started from wind tunnel experiment, climate observation and mathematical simulation, ended up with the mathematical simulation and analysis. By doing these, urban wind environment district division graph for Shenzhen was worked out, which is provided for the later research. This paper also set a plot for example, which includes a official building. By analyzing the wind environment of the plot and the natural ventilation potential of the single building, it is presented that the research of urban wind environment has significant influence on the design of not only plot but also single building, thus related research is very important.By the application efficiency analysis on the natural ventilation of an official building in Shenzhen, it is showed that if natural ventilation design is utilized, during air conditioning period, the time that reaching office indoor comfort by natural ventilation is 39.86% in all. That is to say, more than 570 hours of air conditioning operating time can be saved, thus energy saving goal can be reached. Moreover, if natural ventilation analysis can be considered in order to improve the design in the preliminary period that by using layer-split or zone-split air conditioning system, more air conditioning operation time can be saved, while the natural wind necessity of dwellers can be reached, and indoor air quality can be improved. It is also demonstrated that it is very necessary to utilize natural ventilation technology to meet the need of natural ventilation, and to descend air conditioning energy consumption, thus reaching energy saving goal. When undertaking the research on urban wind environment, several different technological approaches is used according to different wind speed, because there are several different wind speed zone and time zone in Shenzhen. In the end of this paper, several appropriate natural ventilation technologies are discussed according to the characteristics of urban wind environment and the feature and function of official buildings in Shenzhen. While an experiment and simulation on a typical ventilation equipment is done in Shenzhen in order to prove its adapatabilty for office buildings in low-wind-speed-zone, at the same time the equipmen also is able to meet ventilation control when wind get larger on typhoon weather. However, this part is only a brief introduction, which should be regarded according to different climate features for each zone, while the different function requirement of official buildings should also be considered.