Experimental study on the near wake recovery of horizontal axis wind turbines with blades of different trailing edge thickness.

This article investigates the effects of varying trailing edge thickness on the wake recovery and power performance of small horizontal axis wind turbine blades using the NACA4415 airfoil. Through wind tunnel experiments employing a constant temperature hot wire anemometer, blades with trailing edge thicknesses from 0% to 4% chord length (c) were tested, revealing that a 3%c thickened trailing edge optimizes wake expansion, reduces turbulence intensity by up to 3%, and decreases velocity deficits in the near wake region (x/R = 2–4 and x/R = 4). Power measurements under different tip speed ratios (TSR) showed that the 3%c thickened trailing edge blade increased power output by up to 7.01% at TSR = 5 compared to the original sharp trailing edge blade. The study concludes that symmetric thickening of the trailing edge can enhance wake recovery and power generation efficiency in small wind turbines, with implications for wind farm layout and capacity planning, while noting the need for further field validation for full-scale applications.