Experimental and simulation study on a rooftop vertical-axis wind turbine

Abstract

In this study, a small vertical-axis wind turbine (VAWT) was successfully designed and tested to produce electrical energy using renewable wind energy after being installed on the roof of buildings. The VAWT was constructed according to the existing wind source in the Tabuk region in Saudi Arabia. The use of VAWT on roofs is a sustainable solution for producing clean electricity and contributing to a portion of the local electricity consumption. A rooftop wind turbine test was performed to determine the behavior and output of a VAWT under non-constant wind speeds under natural conditions. To verify the resistance of the shear stress and pressure, a computational fluid dynamics (CFD) simulation on the airfoil was conducted. The experimental test results showed that the VAWT can reach its rated power at 9 m/s. The minimum wind speed needed for power production was 3 m/s. The maximum power coefficient obtained during testing was approximately 0.45 at a tip speed ratio of around 1.94. The simulation mesh is constructed with Ansys mesh. Two dimensional (2-D) mapped face meshing, fine, high smoothing mesh was constructed with 50 division numbers and a bias factor of about 150. The grid with 15,000 cells generated the same results as the higher number of cell grids. The simulation equivalent force was about 2.8 N for a single blade, such as 8.5 N in total, which presents an error of about 3%. The CFD simulation and experimental tests on existing forces confirm that the VAWT structure’s resistance can be guaranteed at high wind speeds.

Keywords

• rooftop vertical-axis wind turbine
• h-darrieus wind turbine
• tip speed ratio
• power coefficient
• cfd simulation