**Xiaolei Yang 1,2 , Daniel Foti 3, Christopher Kelley 4, David Maniaci <sup>4</sup> and Fotis Sotiropoulos 5,\***


Received: 11 May 2020; Accepted: 8 June 2020; Published: 11 June 2020

**Abstract:** Subscale wind turbines can be installed in the field for the development of wind technologies, for which the blade aerodynamics can be designed in a way similar to that of a full-scale wind turbine. However, it is not clear whether the wake of a subscale turbine, which is located closer to the ground and faces different incoming turbulence, is also similar to that of a full-scale wind turbine. In this work we investigate the wakes from a full-scale wind turbine of rotor diameter 80 m and a subscale wind turbine of rotor diameter of 27 m using large-eddy simulation with the turbine blades and nacelle modeled using actuator surface models. The blade aerodynamics of the two turbines are the same. In the simulations, the two turbines also face the same turbulent boundary inflows. The computed results show differences between the two turbines for both velocity deficits and turbine-added turbulence kinetic energy. Such differences are further analyzed by examining the mean kinetic energy equation.

**Keywords:** turbine wake; turbine size; large-eddy simulation; actuator surface model
