Respons Of Wind Around Of Buildings For Buildings Layout In Urban Communities

This paper simulated wind field around the building which used the FLUENTsoftware package that had an application widely in the world and had a60%marketshare in the United States. FLUENT is used for simulating compressible flow. Manykinds of solving methods and multiple grid accelerating convergence technologymade FLUENT achieve the best convergence speed and precision to get credibleresults. Through reading a large number of literature data, this article preliminaryestablished the campus of Shandong normal university teaching building windenvironment simulation calculation. Used the experimental data of the wind fieldaround the building in May2010to compare the simulation results and adjust thesimulation scheme. The parameters were revised to recalculate achieved reliable dataand determine the project. Used parameters to simulate three different layout of theresidential type In Jinan in leading the direction of the wind south westerly to thedominant wind direction and wind Northeastern down. The south is high and thenorth is low, the heights of buildings are equal and south low north high typecommunity. The6kinds of situation had carried on the numerical simulation of windfield, the simulated results are analyzed. In addition, the unacceptable gale frequencyin village is analyzed according to every hour of the day2010numericalmeteorological monitoring of Jinan. Get the following conclusions:（1）Using the standard wall function to improve the correction of the standard k-εmodel, the wind turbulence equations are dispersed basing on the finite volume ofsecond-order discrete format. Prove that the scheme combined simulation of windenvironment around the building is applicable, but for large span building shape,length and width are greater than the building height, not simple calculation domainscale according to the height to determine(15h×10h×6h), shall be calculated accordingto the length of the scale of the width to adjust domain （15w×10d×6h）,which is wfor building length, d for building width and h for building height.After adjustment calculation domain to improve simulation precision, the paired T test results with themeasured values of two groups of data difference was not significant.（2）Wind southwestern, changes of wind field are complicated for the buildinglow meteorological north and north south elevation height, because of building scalein inlet direction is larger. The wind flow around the buildings produce small windarea behind of buildings. It produce large wind area on both sides of the first andsecond row buildings. It can result in a different direction vortex on leewardhorizontal side and a clockwise vortex in vertical direction, it make up the dust on theground, affect building air environment. The vortex center position exist in buildingheight about two-thirds,in this position will form the accumulation of pollutants.Only in front of the low rise buildings kona clockwise vortex formation for thebuilding low meteorological south, no obvious vortex formation in residentialbuilding behind the wind gently. So pollutants is more conducive spred for the layoutof the building low meteorological south, when the direction of wind is southwesterly.Wind northeastern buildings and inlet direction is parallel, the influence of windfield is small. The change of wind environment is not big. It is conducive to thediffusion of pollutants inside the village. But building the leeway is small, there maybe people with poor ventilation.（3）It appeared small wind area close to the wall position for windward siderectangular buildings. Buildings in the leeward surface due to the building blocks inthe boundary layer stripping surface buildings. In the leeward building form smallarea and the vortex wind. When the wind flow around cylinder buildings, the windflow along the surface of the building, will reduce the stripping of boundary layeraround the building. Building for wind blocking effect are relatively moderate. Thewind pressure contour on both sides of buildings is lesser, also changes in the leewardwind field building is little. The cylindrical structures can reduce the effect on thewind field.（4）Wind south westerly, the community as a whole for the influence of windfield disappeared in200~300m area leeward side for30m high building plot (Xinzhuang and Wujia).The blocking effect of wind on buildings disappeared in500~600m area leeward side for high50m for floor area. The building is higher and theinfluenced area of wind is larger. Wind Northeastern, due to the scale of buildings inthe direction perpendicular to wind direction is small, buildings and building spanratio is less than1:4, the influence of wind is small. So building scale and inletdirection have the biggest influence to the village. The bigger buildings scale in wind direction, the greater the effect on the wind field. the greater the formation of the localwind field.(5) For inside the village appeared unacceptable gale frequency analysis, foundin the area south of the first row between buildings appear unacceptable wind speedprobability is3.77%, the first row of buildings in eastern area of the southeast andnortheast appear unacceptable wind speed probability is2.60%. Therefore in generalarrangement design, must be set in the two locations windproof green belts, to slowdown the impact of the strong wind weather brings.