Experimental And Numerical Study On Aerodynamics Performance Of Windbreaks

Windbreak is widely used in engineering of wind-proof and dust-proof, theaerodynamics performance of which consists of the performances of wind and thewind resistance. In previous studies on the performances of wind, Scholars havemainly paid attention to the porosity of the windbreak, however few research hasbeen conducted about the influence of the nonuniform hole patterns, the angels tothe wind and the turbulence intensity. Only a relatively small number of researcheshave been done on the aspect of the performance of the wind resistance, and thereisn’t a value for the wind load on the windbreaks specified by the design codes ofChina. To improve the understanding of the aerodynamics performance and getmore detailed information, the pressure-measuring and the velocity-measuringwind tunnel tests on the windbreak model with the porosity of20%have beenconducted, studies on the information of the wake flow filed and the wind loaddistribution on the windbreaks within different hole patterns, angels to the windand turbulence intensity have been carried out, and the method of the numericalsimulation on windbreaks combined with the measurement of the model ofpressure-drop has been established. To verify the feasibility of the numericalsimulation method, the results of the numerical simulation and the experiment havebeen contrasted. The main contents in this paper are shown as following,(1) Based on the analogous theory, the windbreak models and the designmethod of the wind tunnel tests have been studied, the first windbreak model withan interlayer has been created, and the wind pressure information of the windwardside and leeward side of windbreaks has been obtained the pattern design andexperiment design of the wind tunnel tests have been completed. The wake flowfield measurement experiment has been completed.(2) The influence of the nonuniform hole patterns, the angels to the windand the turbulence intensity on the wake flow field and the wind load of thewindbreak has been researched combined with experimental data.(3) The simplified method of the numerical simulation on windbreaks hasbeen presented; the determination test on the model of pressure-drop of windbreakwith different hole patterns has been conducted to determine the pressure losscoefficient, which is the key parameter of the numerical simulation. The effect ofthe hole shape and the nonuniform hole pattern on pressure loss coefficient of thewindbreak has been researched. To verify the feasibility of the numericalsimulation method, the results of the simplified numerical simulation and theexperiment have been contrasted.