NUMERICAL SIMULATION OF 3D STEADY ATMOSPHERIC FLOW AROUND LOW-RISE GABLE ROOF BUILDING

A standard k-ε model, the Reynolds Averaged Navier–Stokes Equations (RANS)turbulence model, is added in a commercial computational fluid dynamics software Fluent 6.3 to numerically simulate the 3D steady wind flow field around standard low-rise building TTU in atmospheric boundary layer. The simulating results are compared with TTU field measured data and Tongji University TJ-2 wind tunnel test data. Then a detailed parametric study is performed for average pressure coefficient and shape factors of low-rise building with gable roof by RNG k-ε turbulence model. The parameters include wind attack angle, roof pitch, eave length, eave height, and ratio of wall length to width. The analysis results show that numerical simulation is a feasible way to study the wind flow around low-rise building and the distributing of wind pressure in the building’s surface. The pressure on the wall of windward is positive, and its shape factor isn’t affected by the geometry of building. The pressure on the wall of leeward is negative. Wind attack angle, Roof pitch and aspect ratios of wall length to height affect both the magnitude and distribution of gable roof pressures; the eave length doesn’t affect the roof pressures. The research provides a foundation for the wind resistance design of this type of buildings.