Research On The Numerical Simulation And Evaluation Of Green Livable Degree In An Urban Community

The unreasonable construction layout always results in local strong wind or low ventilation,low vehicle exhaust dispersion,high building energy consumption and other problems of the green livable problem,which is paid more and more attention.In this paper,we focus on the simulation and evaluation of wind environment,residential area pollutant distribution and building energy consumption,which has important theoretical and applied value for building green livable residential district.On the basis of comprehensive analysis of research status,the wind environment and spread of nitrogen oxides,particulate matter of motor vehicle emissions of a typical urban community were simulated by the computational fluid mechanics method under the local condition of typical wind direction,wind speed and frequency.Wind speed field and pollutant concentration field of different seasons,different wind directions and typical wind speed were obtained.Eight evaluation indices were extracted from the regulatory requirements of green building,urban residential area planning design standard and ambient air quality standard.A comprehensive evaluation index of wind environment was proposed based on local meteorological wind frequency,wind directions and typical wind speed.The comprehensive evaluation system of wind environment was set up by the analytic hierarchy process method.Take a Tianjin residential district as an example,the area and proportion of wind environment and pollutant concentration that do not meet the requirements were obtained and the wind environment comprehensive evaluation index of community in four seasons and whole year were gained.It is 79 in winter,96.49 in summer,93.95 in spring and autumn and 90.8 in the whole year.The cold air infiltration heat loss,hot air exudation loss,total loss of winter and hot air infiltration heat loss,cold air exudation loss,and the total loss of summer were calculated under the prevailing wind condition based on local meteorological conditions and wind environment simulation.The proposed wind environment comprehensive index and calculation method of infiltration and exudation loss of building has theoretical guidance importance on optimizing urban residential building layout and achieving livable and green concept.