Numerical Simulation Of Wind-blown Sand Flow Around A Couple Of Buildings

In recent years,with the changes in global climate,the frequency of dust weather has become higher and higher in the central and western regions of China,and the dimension has become larger and larger.As the wind-sand weather has brought a tremendous impact to production and life,people have begun to study the aeolian sand movement.Building wind-sand load has become one of the necessary factors in the structural design of buildings(especially lightweight and large-span buildings).However,there are relatively few studies on the wind-sand load on the surface of buildings at home and abroad.Therefore,this paper makes use of CFD software to numerically simulate the wind pressure on the surface of buildings and the surrounding wind field in the wind-sand environment.The results have certain reference value for the practical application of the engineering.The main contents of this paper are as follows:1.The research results of wind engineering and building wind load at home and abroad are summarized.The common turbulence models are compared and the turbulence model and numerical method to be selected in this paper are determined.Then,the numerical simulation of the wind pressure of the net wind field of the single building is carried out,and compared with Chinese "Building Load Code"(GB500009-2012),the feasibility of the numerical method selected in this paper is proved.Subsequently,the numerical simulation of the wind-blown flow field with a flat bed surface included sand is carried out,and compared with the wind tunnel test results,which proves the validity of the calculation model of the wind-blown flow field used in this paper.2.Numerical simulations of the flow around two rectangular columns of wind-blown sand flow under two arrangements(parallel and serial).First of all,the numerical simulation of the wind-blown sand flow around the two high-rise buildings with different spacing ratios is carried out,and the surface wind pressure distribution laws and the surrounding wind field characteristics are obtained.In the second place,the numerical simulation of the wind-blown sand flow field around the two high-risebuildings under different sand volume fraction is carried out.At the same time,the relationships between the surface wind pressure distribution laws and the sand concentration,the wind speed around the buildings and the sand concentration are obtained.Through the research and analysis of this paper,the wind pressure characteristics and wind field characteristics of high-rise buildings in the wind-blown sand flow field are summarized.It shows that the sandy airflow has a significant impact on the distribution of building's partial loads.It is one of the factors that must be considered in the actual design and maintenance of the engineering.The results obtained in this paper can provide some reference for the structural design of the building groups.