Parametric Study of Leading-Edge Slat Size and Placement Parameters for achieving optimal Aerodynamic and Acoustic Performance of VAWT

Abstract

Nowadays, small VAWT are receiving more consideration due to their appropriateness in micro-electricity production. Different techniques have been used to improve the efficiency of power. Presently parametric study of leading-edge slat size and placement parameters is conducted to achieve optimum aerodynamic and acoustic performance of VAWT. To validate the methodology, CFD results of 2D AEOLOS VAWT at Tip speed Ratio (λ) of 2.094 are compared with that of OEM provided performance data. Afterwards, acoustic analysis was carried out and results are in good comparison with the technical specification of AEOLOS (1kW) VAWT. Coefficient of Moment Cm, and Coefficient of Power CP, are studied in Ansys Fluent® using unsteady Reynolds- averaged Navier-Stokes (URANS) and turbulence is modeled using improved three equation transition (SST) model. The noise (A- weighted Sound Pressure Level) radiated from VAWT is calculated using the FW-H acoustic codes. Results of the study indicate that minimum overlapping between the main and slat aerofoil is desirable and slat placement angle (β) must be selected less than 15°. As far as slat size is considered there must be a tradeoff between desired aerodynamic performance and acoustic noise level.