On the Aerodynamics of Trailing Edge Serrations at Low Reynolds Numbers

Abstract

This Master thesis presented an aerodynamic evaluation of wing sections with a serrated trailing edge at flow conditions analogous to those of micro aerial vehicles (MAVs). Tests were performed at Reynolds Numbers between 30,000 and 200,000 on two different wind tunnels. A series of serration configurations were considered with different variables including wavelength, amplitude, and shape of serrations. Five serration shapes were used, all with a thin flat plate as a baseline profile: (i) blunt, (ii) triangular, (iii) quadratic bird feather-like, (iv) quadratic membrane-like, and (v) quadratic membrane-like with tapering. Trailing edge serrations affected the wings’ aerodynamic parameters such as CL, CD and CM and reduced the wing sections weight. Results indicated that bird feather-like serrations and quadratic membrane-like ones with tapering provided the highest aerodynamic benefits, accounting for a potential increase in range for MAVs that implement such serrations. Parts of this thesis were presented on the 2020 PNW AIAA TECH Symposium’s Poster session and on the 2022 AIAA Scitech Forum [1, 2].