Abstract

The production of sustainable energy is one of the biggest challenges facing us today. Wind and solar technologies are the leaders for clean energies. Wind energy is in relatively plentiful supply, can be used efficiently and is a nonpolluting power production method. Within this paradigm, building-integrated micro wind turbines are promising low cost renewable energy devices, but are fraught with challenges like low wind speeds and high turbulence intensity. In this thesis, a comprehensive study of increased performance of a wind turbine design inside a diffuser shaped shroud on building roofs is conducted. A commercial Computational Fluid Dynamics (CFD) model is used to simulate unsteady 3D flows inside the diffuser and around the turbine. The meshing strategy and model used is verified using a grid refinement study. The geometric modifications and various non-dimensional parametric studies conducted are also described in detail, along with the relevant discussion of results obtained. Furthermore, the coefficient of power of the turbine is improved from 0.135 to 0.394, representing an improvement of almost 300%. This improvement can largely be attributed to the flanged diffuser shroud design, as well as the modifications made to the blades of the turbine.