A UDF-Based Approach for the Dynamic Stall Evaluation of Airfoils for Micro-Air Vehicles

Abstract

A numerical method for generating dynamic stall using ANSYS Fluent and a user-defined function (UDF), with the complete script shared for reference, is introduced and tested. The study draws inspiration from bird flight, exploring dynamic stall as a method for achieving enhanced aerodynamic performance. The numerical method was tested on NACA 0012 airfoils with corresponding chord lengths of c1=40 mm, c2=150 mm, and c3=300 mm at Reynolds numbers ranging from Re1=2.8×104 up to Re5=1.04×106. Airfoil oscillations were settled for all cases at ω=0.55 Hz. Detached eddy simulation (DES) is employed as the turbulence model for the simulations presented, ensuring the accurate representation of the flow characteristics and dynamic stall phenomena. The study provides a detailed methodology, encouraging further exploration by researchers, especially young academics and students.

Keywords

• aerodynamics
• hysteresis
• NACA 0012
• DES