Numerical Simulation of the Fluid Flow around a Roof Mounted Wind Turbine

Abstract

The aerodynamic performances of a roof mounted small vertical axis wind turbine are evaluated using a Computational Fluid Dynamics (CFD) code and a computer program based on the Blade Element Momentum theory. The CFD code solves the incompressible Reynolds Averaged Navier-Stokes (RANS) equations for the simulation of the flow around a building with a roof mounted wind turbine. These computations are performed with a 3D grid, assuming steady and fully turbulent flow. The CFD results are used to derive the wind velocity vector approaching the wind turbine. Then the aerodynamic performances of the roof mounted wind turbine are determined using a Multiple Stream tube Theory. Beforehand, to check the reliability of the CFD computations, the simulations of the flow around reference buildings are performed and the results are compared with reference data.

Keywords

Computational Fluid Dynamics wind profile flow around building vertical axis wind turbine roof mounted wind turbine

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