Shape optimization of a shrouded Archimedean-spiral type wind turbine for small-scale applications.

Small-scale wind turbines are increasingly gaining importance despite they are still in the shadow of the megawatt-sized wind turbine development boom. Areas far removed from the electricity grid pose great potential for small-scale wind turbines. In such instances an Archimedean-spiral type wind turbine (ASWT) which is a new kind of horizontal-axis wind turbine maybe used for small-scale applications including off-grid power. The ASWT performance is improved in this work by designing a shroud with a flange at its inlet during an optimization technique aims to maximize the coefficient of power (C p). The employed optimizer is an Evolutionary Algorithm over a Kriging interpolative model. A set of straight lines is applied to identify the shape of the shroud. The output power coefficient (C p) is calculated by solving the Reynolds-averaged Navier-Stokes (RANS) equations with the SST k -Ω turbulence model using the commercial code software ANSYS-FLUENT. The simulation results are verified through GCI and validated with an experimental result. It is proved that the optimal shroud design yielded important enhancements in the C p when it is applied to an ASWT. The results indicated that the optimal shrouded ASWT introduces a maximum C p -value of 0.502, which is 2.58 times the C p -value of the bare ASWT (C p = 0.195) at λ = 2.5. • ASWT performance is improved in this work by designing a shroud with a flange. • An optimization technique aims to maximize the coefficient of power (C p). • Employed optimizer is an Evolutionary Algorithm over a Kriging interpolative model. • Numerical investigation is performed by solving 3D Reynolds Navier–Stokes equations. • Results indicated that the optimal shrouded ASWT introduces a maximum C p -value of 0.502. [ABSTRACT FROM AUTHOR]