LARGE-EDDY SIMULATION OF TURBULENT BOUNDARY-LAYER FLOW OVER A URBAN TOPOGRAPHY

도시지형을 지나는 난류 경계층 유동의 대와류 수치모사

Large-eddy simulation has been conducted to simulate turbulent boundary-layer flows over an array of regularly distributed obstacles considering various cases of a wind incident angle. The effect of wind direction was investigated in the square cube array that periodic boundary condition was imposed. Characteristics of the turbulent flow over the obstacle array have been found to be very sensitive to the direction of prevailing wind or of mean wind or of mean pressure gradient but varied with height, specially below the urban canopy. Turbulent statistics are changed sensitively with the direction of mean pressure gradient around 10 degree.