Design and implementation of an aerodynamic balance in a subsonic wind tunnel and validation through numerical and experimental investigations of lift and drag performances on airfoils

DANIEL MARTINEZ; CESAR MEAURIO; DARIO ALVISO; JUAN CARLOS ROLON

Vitória, ES

Congreso; 16 th Brazilian Congress of Thermal Sciences and Engineering; 2016

ABCM

In the present work, we describe the construction of an external force aerodynamic balance of five components for a subsonic open circuit wind tunnel. The wind tunnel used in this study is a EWT (Educational Wind tunnel) of AEROLAB. After analyzing the characteristics that the aerodynamic balance should meet to operate in the wind tunnel, we proceed to make a computer-aided design to carry out the construction. Once the manufacturing of the mechanical structure is complete, the installation of the force sensors and the electronic system for control and data acquisition is performed. A software was developed in order to perform data reading and facilitate the use of the designed instrument.Experiments were carried out by performing measurements of lift and drag forces on several airfoil configurations, at different angles of attack as well as different Reynolds numbers. Validations were made by performing numerical analysis using XFOIL code. The airfoils analyzed are the symmetric NACA 0012, NACA 0018 and the asymmetric Eppler 193. These airfoils were machined using a CNC (Computer Numeric Control) milling machine.