Study On Flow Characteristics Of Rectangular Section With Aerodynamic Optimization

With the popularity of high-rise buildings,the materials become lighter and higher strength,the structures become more sensitive to the wind,so it is very important to optimize its aerodynamic performance.Corner modification of the structure is the most common aerodynamic optimization.However,a regular cut-corner on the structure is the easiest and most economical way.Therefore,we have to make an in-depth study on it.At the same time,there are some bay windows or large balconies on the facades to get more natural light or to optimize the ventilation environment,some buildings have other protruding structures on the facades to meet the design needs.But there is little research on them.In this paper,flow characteristics around the structures with rectangular sections which have different cut-concer ratio or protruding structures on the facades have been studied by using the method of numerical simulation,the main research contents are as follows:For the buildings with cut-corner,the aerodynamic characteristics of cros s section with vary cut-corner ratio are summarized and then put forward the favorable cut-corner ratio to provide suggestions for practical engineering.The aerodynamic performance and flow characteristics of the square section and the typical rectangular section with the aspect ratio of 1:2 are investigated by changing the size of the corner modification,where the aerodynamic parameters such as mean pressure coefficient,fluctuating lift coefficient and Strouhal number are taken as indexes.The aerodynamic performance of the square section and the typical rectangular section with vary size of the corner modification was obtained and a favorable size under the same concave area is proposed,provides reference for the design of practical engineering.For the buildings with protruding structures on the facades,the variation law of the aerodynamic performance about the sections with the change of related parameters are analyzed,and proposed a favorable arrangement of protruding structures on the facades.Based on the design of the bay windows in practical engineering,study on flow characteristics around the square section and the typical rectangular section after arranging protruding structures on the facades by numerical simulation.By changing the position and the density of protruding structures to explore the aerodynamic performance with the change of various related parameters,and the differences between square section and typical rectangular section are compared.Through the analysis,the law of the efficiency about optimized structures is obtained,proposed a favorable arrangement of protruding structures on the facades.The flow characteristics about the favorable cross-sections of buildings have been conducted.The efficiency of the optimized cross sections of buildings under whole wind direction is discussed,and the optimal treatments are put forward according to the different optimization forms and optimized cross section s.On the basis of previous studies,the numerical simulation of the optimized sections under the whole wind direction are carried out.The efficiency of each optimizated measure under whole wind direction is studied by comparing with prototypes.The favorable wind direction and the changes compared with prototypes are obtained to give suggestions on designing structures under different wind directions.